Abstract:
A locomotive is provided that includes:
       a receiver operable to receiving a locating signal, the locating signal indicating a current spatial location of a selected locomotive and   a processor operable to (a) determine that the selected locomotive has entered, is entering, and/or is about to enter a spatial zone having at least one controlled parameter, the controlled parameter being at least one of a fuel combustion emissions level and a noise level and (b) configure the operation of the selected locomotive to comply with the controlled parameter.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims the benefits, under 35 U.S.C. § 119(e), of U.S. Provisional Application Ser. No. 60/558,077, filed Mar. 30, 2004, of the same title to Watson, et al., which is incorporated herein by this reference. 
    
    
     FIELD 
     The present invention relates generally to locomotives and specifically to a hybrid locomotive which is suitable for operation under controlled environmental conditions. 
     BACKGROUND 
     Conventional stand-alone locomotives have output power typically ranging from approximately 300 horsepower (for example, locomotives used in mining and tunneling) to 6,000 horsepower (for example, locomotives for long haul cross-country freight trains). In many applications, a number of locomotives may be used in a consist for freight haulage or commuter trains for example. 
     Conventional railroad locomotives are typically powered by diesel-electric systems or by diesel-hydraulic systems. It is known that a hybrid locomotive or a hybrid locomotive/tender car combination can be used to capture and store energy that is otherwise wasted by incorporating an energy storage system (battery pack, capacitor bank, flywheel assemblies or combinations of these systems). The energy storage system may be charged by an on-board engine, by another hybrid or conventional locomotive in the consist, by a regenerative braking system or by an external source. The stored energy may be used to power the traction motors of the energy storage car or the traction motors of other operative members of the consist. 
     Donnelly has disclosed the use of a battery-dominant hybrid locomotive in U.S. Pat. No. 6,308,639 which is incorporated herein by reference. Donnelly et al. have disclosed a method of monitoring, synchronizing and optimizing the operation of the locomotive drive train in U.S. patent application Ser. No. 10/649,286 and have also disclosed a method of allocating energy amongst members of a consist in U.S. patent application Ser. No. 11/070,848, both of which are also incorporated herein by reference. 
     In many areas where rail use is widespread, especially large urban settings, there are special requirements for emissions and noise control which are becoming more and more stringent. Commuter and short haul freight routes typically involve many starts and stops and often involve significant idling time. Many of these routes also may pass over significant grades. While conventional diesel locomotives are achieving higher emissions standards and fuel economy, there are many situations such as partially enclosed or underground stations, tunnels or densely populated areas where low emissions and moderate noise operation or no emissions and low noise operation are required and these requirements cannot always be met by conventional diesel locomotives. 
     There remains a need for hybrid diesel-electric or diesel-hydraulic locomotives which are capable of operation, including high acceleration capability, at very low or zero emission and low noise levels such as would be required, for example, by commuter trains entering and exiting underground stations. 
     SUMMARY 
     These and other needs are addressed by the various embodiments and configurations of the present invention which are directed generally to a method for monitoring, controlling and/or optimizing the emission and profile for a hybrid locomotive or consist of hybrid locomotives. 
     In a first embodiment of the present invention, a method for operating a locomotive is disclosed that includes the steps of (a) receiving a locating signal indicating a current spatial location of a selected locomotive; (b) determining that the selected locomotive has entered, is entering, and/or is about to enter a spatial zone having at least one controlled parameter where the controlled parameter is one or more of a fuel combustion emissions level and a noise level; and (c) automatically configuring the operation of the selected locomotive to comply with the controlled parameter. 
     The locating signal can be any suitable mechanical, wireless or wired signal and is preferably emitted by a Global Positioning System, a radio, a cell phone, a transponder and/or a mechanical locator situated along the track. 
     The selected locomotive can be any rail vehicle. For example, the rail vehicle can be a locomotive having a number of prime movers, with the prime movers being selectively operated as needed to meet required energy needs while complying with one or more controlled parameters. For example, a first subset of prime movers is operated while a second subset of the prime movers is not operated. Commonly, the selected locomotive is a dual-mode hybrid vehicle having a large energy storage capability, a substantial power generating system and a regenerative braking system. The vehicle is automatically managed to turn its engines off when emissions-free operation is required; or to turn some engines off or to idle when low emissions operation is required; or to turn the engines on to boost locomotive acceleration as required, for example when leaving a station. 
     Typically, locomotives are subject to emissions levels of non-methane hydrocarbons (HC), carbon monoxide (CO), nitrous oxides (NOxs) and particulate material (PM). These are subject to minimum prescribed values by regulations in effect at any one time. These regulations may change from time to time, usually becoming more stringent. The levels of any of the above emissions are typically expressed as a mass of the emitted pollutant per unit power-time (e.g., grams per kilowatt-hour) where the power is the power delivered by the locomotive engine. In a hybrid, power is delivered by a combination of one or more engines and an energy storage unit and therefore a hybrid can operate at a given power level of which only a fraction is provided by the prime mover(s). As used herein, “emissions free” or “zero emissions” preferably refers to average levels of emitted pollutants that are at least less than about 10% of the minimum values set by the regulations in effect. It is more preferable that “emissions free” or “zero emissions” refer to the condition that all the prime movers are turned off. As further used herein, “low emissions” refers to average levels of emitted pollutants that are at least less than about 50% of the minimum values set by the regulations in effect. 
     Another pollutant is sulphur dioxide (SO 2 ) which is dependent on the specific fuel used. This pollutant is also subject to a minimum value by regulations in effect at any one time and is also typically expressed as a mass of the emitted pollutant per unit power-time where the power is the power delivered by the locomotive engine. As used herein, “emissions free” or “zero emissions” commonly refers to average levels of SO 2  that are at least less than about 10% of the minimum values set by the regulations in effect. It is most preferable that “emissions free” or “zero emissions” refer the condition that all the prime movers are turned off. As further used herein, “low emissions” commonly refers to average levels of SO 2  that are at least less than about 50% of the minimum values set by the regulations in effect. 
     Noise levels are typically measured 30 meters perpendicular to the locomotive and are expressed in dBa over a given range of audible frequencies, typically from 250 to 1,000 Hertz. Power plant noise levels may be prescribed for stationary locomotives in an idling or throttled up mode and also in various passer-by or moving modes. As used herein, moderate noise level commonly refers to average noise at least about 3 dBa less than the regulations in effect for a conventional locomotive of equivalent total power and low noise level commonly refers to average noise at least about 6 dBa less than the regulations in effect for a conventional locomotive of equivalent total power. The averages of emissions and noise are determined over the time period in which the corresponding operational mode is employed by the hybrid locomotive. 
     The hybrid locomotive is commonly comprised of at least a prime mover, an energy conversion device to convert the energy output by the prime mover into a form suitable for storage or propulsion, an energy storage unit, a supply of fuel for the prime energy source and appropriate controls, all mounted on a frame which includes two or more truck assemblies, each truck assembly being further comprised of AC or DC traction motors each of which may be controlled by its own inverters and/or chopper circuits. The hybrid locomotive is additionally provided with a dynamic braking system that includes a regeneration system for transferring some or all of the energy recovered from braking to the energy storage system. 
     As can be appreciated, regulations for engine emissions and engine noise can vary from country to country and, within countries, from state to state or province to province. In addition, regulations change over time as new technology is developed and mandated. The following tables illustrate some emissions and noise regulations currently in effect in the United States for conventional (non-hybrid locomotives). The emissions regulations in California are somewhat more stringent. 
     
       
         
               
             
               
             
               
               
               
               
               
             
           
               
                   
               
               
                 Tier 2 Emissions Standard for US Locomotives (2005 and Later) 
               
             
          
           
               
                 Duty 
               
             
          
           
               
                 Cycle 
                 HC, g/bhp-hr 
                 CO, g/bhp-hr 
                 NOx, g/bhp-hr 
                 PM, g/bhp-hr 
               
               
                   
               
               
                 Line-Haul 
                 0.3 
                 1.5 
                 5.5 
                 0.20 
               
               
                 Switcher 
                 0.6 
                 2.4 
                 8.1 
                 0.24 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 30 Meter Test, Noise Standard, 
               
               
                 Locomotives Manufactured After Dec. 31, 1979 
               
             
          
           
               
                 Noise Source 
                 Weighted Sound Level in dB 
               
               
                   
               
               
                 Stationary, Idle 
                 70 
               
               
                 Stationary, all other throttle settings 
                 87 
               
               
                 Moving 
                 90 
               
               
                   
               
             
          
         
       
     
     In another embodiment of the present invention, a hybrid locomotive operates in a plurality of operating modes which include one or more of:
         zero emissions;   specified low emissions;   maximum fuel economy;   maximum energy recovery (optionally including with engines off);   maximum power for acceleration;   low noise levels;   moderate noise levels;       

     In a preferred configuration, a single hybrid locomotive is configured to operate in a variety of operational and/or environmental states by automatically or manually switching between control algorithms. The control algorithms can be software executed by a central processor and/or a logic circuit that is selectively activated when the corresponding control algorithm is invoked. 
     Under a first control algorithm, the hybrid locomotive can operate in its zero emissions mode by shutting off(or continuously deactivating) its prime mover(s) and operating primarily from its energy storage unit. In other words, when the first control algorithm is invoked at least most of the energy to operate the traction motor(s) is removed from the energy storage unit. 
     Under a second control algorithm, the hybrid locomotive can operate at a specified low emissions mode by operating its prime mover at a specified emissions level (including idling) and supplementing any required additional power from its energy storage unit. Under this algorithm, the prime mover is one or more of (a) activated and deactivated intermittently, (b) intermittently activated but not transmitting power (e.g., idling); and (c) activating and transmitting power to provide energy to the energy storage unit. As in the first operational mode, at least most of the energy to operate the traction motor(s) is removed from the energy storage unit. 
     Under a third control algorithm, the hybrid locomotive prime mover operates freely. In this mode, the prime mover provides at least most of the energy required to operate the traction motor(s). This typically means that energy is not removed and/or intermittently removed from the energy storage unit. Preferably, the prime mover is operated at maximum fuel economy by operating at or near their optimum fuel-conservative operating regime; supplementing any required additional power from its energy storage unit; or returning any excess power to its energy storage unit. With many diesel engines, the optimum fuel-conservative operating point may not be the minimum emissions operating point. Most engines can be characterized by a fuel map which plots output power (kW) versus engine rpms with contours of constant specific fuel consumption (kg/kW-hr). Additionally, engine maps may also show contours of constant specific emission levels for each type of pollutant. Such maps, stored in an on-board computer, would allow an algorithm to shift engine operation to slightly better fuel efficiency or lower emissions at a given rpm or power, when required. 
     Under a fourth control algorithm, the hybrid locomotive can operate in maximum acceleration mode where propulsive power to the traction motors is provided by both its prime mover(s) and energy storage system operating together at or near their respective maximum power ratings. 
     Under a fifth control algorithm, the hybrid locomotive operates in braking mode and maximizes its energy recovery from its regenerative braking system so that it can more readily operate in its other controlled emissions modes. In this mode, the locomotive may also be operated by shutting off its prime mover(s), providing at least some of the energy generated by regenerative braking to the energy storage unit, and operating all required auxiliary power solely from its energy storage unit. 
     Other embodiments involve operating a consist of locomotives, at least one of which is a hybrid locomotive. An important feature of these embodiments of the invention is that the entire consist must have the ability to operate in emissions free mode over a significant portion of its route, such as for example a long tunnel or an underground station where the train must stop, for a reasonable period of time and in low emissions mode over another substantial portion of its route, such as for example entering an open-air station or traveling through an area under strict emissions controls. 
     In a first consist embodiment, at least two of a hybrid locomotive and energy tender car form a locomotive consist where the operation of each hybrid locomotive and energy tender car has the autonomous ability to operate in one or more of the operational and environmental states described above. This embodiment might be preferred, for example, if all members of the consist have the same configurations of hybrid locomotives and energy storage tender cars. In this embodiment, all of the members of the consist must have a regenerative braking system. 
     In a second consist embodiment, at least two of a hybrid locomotive and energy tender car form a locomotive consist where the operations of a number of the members of the consist are co-ordinated to maximize the effectiveness of the operational and environmental states described above, by a master controller in communication with all the members of the consist. This embodiment might be preferred, for example, if various members of the consist have differing configurations of hybrid locomotives and energy storage tender cars. In this embodiment, all of the members of the consist commonly have a regenerative braking system. 
     In a third consist embodiment, at least two of a hybrid locomotive and energy tender car form a locomotive consist where the operations of a number of the members of the consist are co-ordinated to maximize the effectiveness of the operational and environmental states described above, by a master controller in communication with all the members of the consist and with the ability to allocate energy between the various members of the consist. The method of allocating energy amongst members of a consist was previously disclosed in U.S. patent application Ser. No. 11/070,848, filed Mar. 1, 2005, which is incorporated herein by reference. This latter feature means that consist members are interconnected by a direct DC current power bus for exchanging electrical energy. This embodiment is most preferred for many configurations of hybrid locomotives and energy storage tender cars since imbalances in energy storage between members can be corrected. In this embodiment, at least one of the members of the consist has a regenerative braking system. Not all of the members of the consist need have a regenerative braking system since energy can be transmitted to or received from other consist members. 
     In a fourth consist embodiment, a method is provided for managing the environmental states of a consist of locomotives where at least one of the members of the consist is a hybrid locomotive, at least one of the consist members is not a hybrid, and the consist is operated at low emissions or zero emissions mode over a substantial portion of its route. In this embodiment, the non-hybrid members of the consist may be required to idle (low emissions mode) over a substantial portion of the route and to be turned off (zero emissions mode) over another substantial portion of the route. The consist is managed by a master controller in the lead hybrid locomotive and is in communication with all the members of the consist. This embodiment is applicable for consists which may contain non-hybrid members such as conventional diesel-electric or diesel-hydraulic locomotives. If consist members are interconnected by a direct current power bus for exchanging electrical energy, then the master controller may have the ability to allocate energy between the various members of the consist. This would include being able to transfer energy to or from the traction motors of the non-hybrid members of the consist. 
     In another embodiment, at least two of a hybrid locomotive and energy tender form a part of a locomotive consist having one or more independently controllable features. These independently controllable features may include, for example, the total amount of tractive effort applied, the operation of the prime power sources, the amount of stored energy used, the amount of power applied by either or both of the prime power sources and energy storage systems, control of wheel slip, control of wheel skid, amount of regenerative braking energy stored and amount of energy, if any, transferred to other locomotives in the consist. Independent control of features such as described above can be effected by predetermined or programmable logic in an on-board programmable logic controller, a microcomputer, an industrial computer or the like. Control may also be accomplished for each member in the consist from the lead hybrid locomotive, or from the lead hybrid locomotive to the adjacent hybrid locomotive and then daisy-chained from each neighboring member of the consist to the next utilizing predetermined or programmable logic in on-board programmable logic controllers, microcomputers, industrial computers or the like. Control may be by any number of communication methods such as for example, by hard wire from locomotive to locomotive, radio telemetry, other forms of wireless communication, and/or audio and/or video linkage telemetry. 
     As can be appreciated, members of the consist need not be adjacent to one another and can be located anywhere in the train. It is therefore possible, with a long train and with consist members at various positions within the train, that different consist members may be in different operating zones. For example, the lead hybrid locomotive may be in an emissions free zone (such as for example a tunnel) while the hybrid consist member at the end of the train may be in a low-emissions zone or ascending a grade where it can be operating in maximum power mode. 
     The above-described embodiments and configurations are neither complete nor exhaustive. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below. 
     As used herein, “at least one . . . and”, “at least one . . . or”, “one or more of . . . and”, “one or more of . . . or”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, and A, B and C together. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic side view of a typical hybrid locomotive of the present invention. 
         FIG. 2   a  is an example of a main flow chart of automated decision making for controlling various hybrid locomotive operating modes. 
         FIG. 2   b  shows a simple state-of charge diagram typical of a lead-acid battery system. 
         FIG. 2   c  shows a simple state-of charge diagram typical of a nickel-zinc battery system. 
         FIG. 3  is an example of an emissions free operating mode flow chart. 
         FIG. 4  is an example of a low emissions operating mode flow chart. 
         FIG. 5  is an example of a maximum fuel economy operating mode flow chart. 
         FIG. 6  is an example of a regenerative braking operating mode flow chart. 
         FIG. 7  is an example of a maximum acceleration operating mode flow chart. 
         FIG. 8  shows an example of a typical velocity profile between two stations. 
         FIG. 9  shows an example of a possible of engine power profile between two stations. 
         FIG. 10  shows an example of a possible of battery power profile between two stations. 
         FIG. 11  illustrates the events of the engine and battery operations in relation to the velocity zones of  FIG. 8 . 
         FIG. 12  shows the total power profile corresponding to the engine and battery power profiles of  FIGS. 9 and 10 . 
         FIG. 13  is an example of a flow chart for automated decision making for controlling engine operation in a zone or subzone that is part of a typical rail route. 
         FIG. 14  shows an example of a grade profile over a typical rail commuter route. 
         FIG. 15  shows an example of station to station velocity profiles over a typical rail commuter route. 
         FIG. 16  is a schematic of a portion of a rail commuter route from a station to another station showing examples of various zones. 
         FIG. 17  is of a portion of a rail commuter route to a terminus station showing examples of various zones. 
         FIG. 18  shows the amounts of energy delivered by the engines and the battery pack for various purposes for a typical round trip rail commuter route. 
         FIG. 19  shows the sources of energy input and output for the battery pack for a typical round trip rail commuter route. 
         FIG. 20  shows the SOC of the battery pack for a typical round trip rail commuter route. 
         FIG. 21  is a schematic side view of small consist of hybrid locomotives according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     This invention is preferably directed to dual-mode hybrid locomotives whose power for acceleration may be provided by both an energy storage unit such as for example a large battery pack and a power generating system such as for example one or more diesel engines. The energy storage unit is capable of providing propulsive and auxiliary power without generating emissions by operating for substantial periods with the prime mover(s) idling or turned completely off. The prime mover(s) are used at different times to provide all the required power; some of the power by augmenting the power supplied by the energy storage system; none of the power when idling or shut off. The prime mover(s) when providing power may provide some or all of the power for propulsion, charging the energy storage system and an auxiliary power system. 
       FIG. 1  is a schematic side view of a hybrid locomotive of the present invention illustrating the functional relationships of the principal components a hybrid locomotive with regenerative braking. The hybrid locomotive has a control cab  101 . The prime power is provided by one or more prime movers  102 . The engines  102  are used to drive a power conversion unit  103  which provides DC electrical power to a DC bus  104 . An energy storage unit  105  is also connected to the DC bus. Power from the DC bus  104  can flow to or from the energy storage unit  105  or to a plurality of traction motors  106 . Typically, the traction motors  106  each drive an axle and wheel pair  107 . As can be appreciated, the DC bus  104  can provide power to the traction motors  106  simultaneously from both the prime movers and the energy storage unit. When blocking diodes are used in the power conversion unit  103 , power cannot flow back to the engines  102 . The DC bus  104  may also transmit electrical power to an auxiliary power supply (not shown) such as might be used to operate the locomotive&#39;s lighting and air-brake system for example. If the traction motors  106  are AC motors, they receive AC power by means of inverters (not shown) connected to the DC bus  104 . Alternately, if the traction motors  106  are DC motors, they receive DC by means of chopper circuits (not shown) connected to the DC bus  104 . When in braking mode, the traction motors  106 , now acting as a generators, return power to the DC bus  104 . The regenerative braking is typically accomplished by externally exciting the traction motors  106  that power the drive axles and converting them to electrical generators during a braking phase. Again, because of blocking diodes in the power conversion unit  103 , power from regenerative braking cannot flow back to the engines  102 . Power can flow back to the energy storage unit  105 . When a controller determines that the state-of-charge of the energy storage unit  105  reaches a predetermined upper limit, the excess energy from dynamic braking is transferred, by opening switch (not shown), to resistance grids  108  to be dissipated. 
     The engines are large enough to provide a significant portion of the instantaneous output power of the locomotive and therefore require a fuel tank  109 . The fuel tank  109  can be located inside the locomotive or carried underneath as a belly tank or can be both. The capacity of the fuel tank is preferably in the range of 500 to 6,000 gallons. The aggregate power rating of the engines is preferably in the range of 100 to 2,500 kW. The storage capacity of the energy storage unit is preferably in the range of 500 to 2,500 kW-hrs. 
     The prime power is provided by one or more prime movers and can be any suitable power source such as for example one or more diesel engines, gas turbine engines, microturbines, Stirling engines, spark ignition engines or fuel cells. The power conversion unit may be an alternator/rectifier, for example. In the case of a prime mover such as a bank of fuel cells, the power conversion unit may be a simple chopper or a more versatile DC to DC buck/boost circuit. The energy storage system may be, for example, a battery pack, a bank of capacitors, a compressed air storage system with an air motor or turbine, or a flywheel of which a homopolar generator is an example, or a combination of these. The traction motors may be, for example, AC induction motors, DC motors, permanent magnet motors or switched reluctance motors. If the motor is an AC motor, it receives AC power by means of an inverter connected to the DC bus. Alternately, if the motor is a DC motor, it receives DC power using for example a chopper circuit connected to the DC bus. 
     In one configuration, the present invention incorporates a prime mover comprised of high efficiency internal combustion engines such as for example a diesel engine with modern emission controls. These devices permit simultaneous reduction of NOx and particulates, for example, and therefore solve many of the emissions problems associated with combustion engines. When in operation, the engines may be operated with maximum fuel efficiency and/or minimum emissions per unit of fuel consumed. When turned on the engine(s) may assist in propulsion and provide auxiliary power and/or charge the energy storage system, depending on the controller algorithm. Otherwise the engine(s) can be turned off and the hybrid locomotive can be operated in emissions-free mode. An important objective of the present invention is to minimize and control fuel usage with the engines. Since some irrecoverable energy is required to charge an energy storage system, it is usually always preferable to use engine power directly for propulsion and auxiliary power when possible. Only when engine energy is being wasted is it preferable to transfer it to an energy storage unit. Otherwise, it is usually preferable to operate the engine(s) in maximum fuel efficiency and/or minimum emissions per unit of fuel mode. 
     The propulsion system for the present invention may be that used in hybrid diesel-electric or hybrid diesel-hydraulic locomotives. In the latter cases, one traction motor may be used to provide shaft power to a gearbox and drive shaft system as disclosed in U.S. application Ser. No. 11/075,550, filed Mar. 8, 2005, by the present inventor and incorporated herein by reference. The hybrid locomotive of the present invention has a regenerative braking system that allows substantial energy to be returned to the energy storage unit during braking. This recovered energy can often provide a major source of recharging energy while operating in a reduced emissions mode or an emissions-free mode. 
     Because a commuter or short haul freight route involves considerable acceleration, braking and stopping, as well as periods where emissions-free operation may be required, power requirements may be highly variable. In addition, auxiliary power such as, for example, required by air-conditioning for a commuter train, can be a substantial fraction of the overall power requirement. Although average power required over the entire route may be relatively modest, peak power excursions during acceleration out of a station; operating at high speed; or ascending a grade, can be substantially higher than the average power over the route. Therefore, a locomotive with engine(s) that can be idled or turned off for long periods coupled with a substantial energy storage capability is preferred and is ideal for enabling an emissions management and control strategy. 
     In a preferred embodiment, the hybrid locomotive is provided with a device for determining its location at all times and at all locations along its intended route. For the example of a commuter locomotive, the capability can be provided by, for example, a Global Positioning System (“GPS”) device, a radio, a cell phone or by a transponder or mechanical locator situated along the track. The locator device allows an on-board computer, which contains a detailed map of the commuter route and route emissions requirements, to determine when the locomotive is in a zone where any of a number of emissions and noise restrictions must be observed or where certain locomotive performance is required. An example of the latter may be a requirement for high acceleration such as, for example, exiting an underground station. 
     The on-board computer automatically manages the operation of the engines (one or more engines on or idling, or all engines off) and the state-of-charge (“SOC”) of the energy storage system. It does so by projecting the energy and power requirements of the vehicle for each section or zone of the vehicle&#39;s route. The emissions management system ensures that the energy storage system is maintained within its preferred SOC range as much as possible while retaining enough capacity to provide the locomotive power requirements, including auxiliary power which can be substantial. The management system also ensures that the energy storage system is maintained within its preferred SOC range as much as possible while retaining enough capacity to absorb considerable recoverable energy from a regenerative braking system. Within these and other constraints, the management system further ensures that all emissions and noise restrictions, as well as any regulatory restrictions, along the route are met. As can be appreciated, the prime mover(s) are the principal source of emissions and noise. When operating in emissions free or low emissions mode, the noise levels of the locomotive are therefore also reduced. However, it may be required to turn off or idle one of more prime movers solely to comply with a noise requirement. 
     In another aspect of the present invention, an important objective is to manage the operation of the engines to comply with various environmental and regulatory restrictions while maximizing engine fuel efficiency, engine and energy storage apparatus lifetimes and minimizing operating costs. As will be shown, this management process is complex and not always suited to manual control, especially with a hybrid system. It is the objective of the present invention to disclose an automated hybrid locomotive engine, energy storage and environmental parameter management process that takes advantage of automated knowledge of the train&#39;s location at all times along a predetermined route using an on-board route map in conjunction with a locator which determines the locomotive&#39;s location and zone. 
     In yet another aspect of the present invention, an on-board computer control system may also have the ability to generate detailed route profiles and store these profiles in an on-board computer data bank of prior route profiles which quantify these past routes by a set of descriptors. These descriptors may include data on, for example, energy storage SOC, engine usage, locomotive speed, locomotive acceleration, locomotive deceleration, outside or ambient temperature, ambient precipitation, ambient wind speed and direction, rail condition (dry, slippery or even an estimate of adhesion coefficient), train length, train weight (e.g., passenger load), maximum power available from the energy storage unit, maximum power available from the prime mover, specific fuel consumption of the prime mover, total power usage (including auxiliary power usage), percent rail grade, track curvature, and the like. This data can be tagged with route location and time at closely spaced intervals such as for example, every second or every 5 meters. As part of the automated decision making process for controlling engine in a zone or subzone, the computer program can query the database of prior route profiles and compare previous operational zone profiles with the profile being computed for the current zone. This process can be used to adjust, if necessary, the profile for the current zone. The comparison can be made, for example, by progressively narrowing the prior profiles on the basis of descriptors associated with the profiles. For example, prior profiles where the temperature, wind and rail conditions are similar would be given a higher weighting than those with significantly different weather or rail conditions. Additionally, prior profiles could be adjusted for number of commuter cars in the train consist and even for passenger load. To implement this process, it is part of the present invention that the hybrid locomotive is provided with a device for determining outside weather, in addition to its location, at all times and at all locations along its intended route. This capability can be provided by, for example, existing on-line weather services through, for example, a radio, a cell phone or other wireless communications device that is connected to the on-board computer. Additional optional information may also be provided to the on-board computer on passenger load which affects train weight and hence energy generation and emissions control. The number of commuter cars in the train consist can be input by the train engineer or it can be determined automatically by the on-board computer from detailed data on power and acceleration coupled with a data base of commuter car and locomotive weights. 
     The energy storage tender car described in U.S. Pat. No. 6,615,118 provides additional power for the primary locomotive by storing excess energy from a conventional diesel locomotive or energy captured from a regenerative braking system. The tender car described in U.S. Pat. No. 6,615,118 cannot however, operate with the main locomotive&#39;s diesel engine shut off and therefore cannot operate in an emissions-free mode. The invention described in U.S. Pat. No. 6,615,118 embodies an energy management system. By contrast, the present invention embodies an emissions management system for a hybrid locomotive or consist of hybrid locomotives. A rail route may have sections where no emissions are allowed such as, for example, tunnels and underground stations. The route may have other sections where only low emissions are allowed such as, for example, sections entering and exiting open-air passenger stations. A fundamental condition of operations where emissions must be managed is that the locomotive or locomotive consist must be able to operate in zero emissions mode over a substantial portion of its route and in low-emissions mode over another substantial portion of its route. The same principles apply for operation when low or moderate noise levels are required. 
       FIG. 2   a  is an example of a main flow chart of automated decision making for controlling various hybrid locomotive operating modes for controlling power generation, energy storage and emissions over a typical rail route. As can be appreciated, similar flow charts can be applied to noise. This cycle of decisions can be executed continuously (for example every 1 second) or intermittently (for example every minute) or at intervals in between by a predetermined computer program or by a computer program that adapts, such as for example, a program based on neural network principles. There are four predetermined SOC levels that are used in this example, although additional levels may be defined. The predetermined levels are percentages of full charge. Examples of typical predetermined levels for A, B, C and D are shown in the following table for two types of energy storage battery chemistries, lead acid ( FIG. 2   b ) ad nickel-zinc ( FIG. 2   c ). These predetermined levels may change with improvements in battery technology and with charging algorithms used. They may also be quite different for other battery chemistries or other energy storage technologies. 
     
       
         
               
               
             
               
               
               
               
             
           
               
                   
               
               
                 Typical 
                   
               
               
                 Predetermined 
                   
               
             
          
           
               
                 SOC Levels 
                   
                 Nickel-Zinc 
                 Lead-Acid 
               
               
                   
               
               
                 A 
                 Maximum Normal Charge 
                 95% 
                 90% 
               
               
                 B 
                 Minimum Allowable Charge 
                 15% 
                 30% 
               
               
                 C 
                 Minimum Operating Charge 
                 10% 
                 20% 
               
               
                 D 
                 Preferred Operating Charge 
                 70% 
                 70% 
               
               
                   
               
             
          
         
       
     
     In the following examples, full charge is 100% and total discharge is 0%. In the above table and as shown in  FIG. 2   b , predetermined level A %  205  represents the highest SOC without causing excessive gas generation in the cell. Predetermined level B %  208  represents the lowest SOC before cell capacity begins to rapidly decline and further use of the energy storage system is damaging to the cells. Predetermined level C %  207  represents the lowest SOC before cell lifetime is adversely affected and represents the SOC above which the energy storage unit is preferably operated. Predetermined level D %  206  represents a preferred SOC that has some headroom for recovering energy from regenerative braking and enough capacity for sustained operation in emissions free mode, low emissions mode and maximum acceleration mode. 
     As shown in  FIG. 2   a , an automated cycle begins  210 , the first step  211  in the decision cycle is to determine the SOC of the energy storage system, which may be determined by any number of well known methods such as, for example, by measuring voltage or by integrating current inputs and outputs. The next step  212  in the decision cycle is to determine the train&#39;s location along its route at the time in question. This capability can be provided by, for example, a Global Positioning System (“GPS”) device or other means as described previously. The next step  213  in the decision cycle is to determine the zone that the train is located in along its route. This can be done, for example, by using the train&#39;s determined location and an on-board computer containing a detailed physical (2D or 3D as required) map of the commuter route and route requirements, to determine zone where any of a number of emissions and noise restrictions must be observed and where certain vehicle performance is required. An example of the latter may be high acceleration such as, for example, exiting an underground station. The next step  214  is to determine the location of the consist member in the train, typically from the train location device in the lead hybrid locomotive and from the knowledge of the number of cars that the consist member is removed from the lead locomotive. If there is only one locomotive, this step is trivial. In a long train where consist members may be at various locations, this step may be important since consist members can be located in different operating zones. The final step  215  is to look ahead as described previously to project energy and power requirements of the locomotive or consist for each section or zone of the train&#39;s up and coming route. Once the above information is determined, one of five operating modes is selected for the locomotive or other consist member. These are a zero emissions mode  221 , a specified low emissions mode  222 , a maximum fuel economy mode  223 , a maximum energy recovery mode  224  and a maximum power or acceleration mode  225 . 
       FIG. 3  is an example of decision making for a hybrid locomotive operating in an emissions free zone  301  and refers to  FIG. 2   b  or  2   c  for SOC references. If the SOC of the energy storage system is greater than D %  302 , then the engine(s) are turned off  303  and the train power is provided by energy storage unit only. If the SOC of the energy storage system is less than D % but greater than C % by an acceptable margin  304 , then the engine(s) are turned off  303  and the train power is provided by energy storage unit only. An acceptable amount is determined by the look-ahead step and is a SOC that is sufficient to meet projected energy storage requirements. If the SOC of the energy storage system is less than an acceptable amount above C %, then the train must be stopped  305  and the engines turned on to charge the energy storage unit back to a level greater than C % by the acceptable or preferably to D % or greater. Once the train can proceed, the algorithm returns to the beginning of the cycle  306 . It is appreciated that the train must be stopped if the SOC is less than an acceptable amount above C % because emissions free operation is only possible using the energy storage system with the engine(s) turned off. 
       FIG. 4  is an example of decision making for a hybrid locomotive operating in an low or restricted emissions zone  401  and refers to  FIG. 2   b  or  2   c  for SOC references. If the SOC of the energy storage system is greater than A %  403 , then the engine(s) can be idled or turned off  404  and the train power is provided by energy storage unit only  405 . This operation in zero emissions mode can be continued until the SOC is reduced somewhat below A %. If the SOC of the energy storage system is greater than D %  402 , then train power is provided by some of the engines or, by the engines operated intermittently and by the energy storage unit  408 . If the SOC of the energy storage system is less than D % but greater than C % by an acceptable margin  406 , then train power is provided by some of the engines or, by the engines operated intermittently and by the energy storage unit  408 . If the SOC of the energy storage system is less than an acceptable amount above C %, then the train must be stopped and the engines turned on to charge the energy storage unit  407  back to a level greater than C % by the acceptable amount. In low-emissions mode, the acceptable amount is typically less than the acceptable amount in zero emissions mode because some engine power can be used. Once the train can proceed, the algorithm returns to the beginning of the cycle  409 . 
       FIG. 5  is an example of decision making for a hybrid locomotive operating in maximum fuel economy operating mode  501  and refers to  FIG. 2   b  or  2   c  for SOC references. This mode is typically used whenever there are no emissions restrictions and there is a desire for a balance of high performance and low fuel consumption. If the SOC of the energy storage system is greater than A %  502 , then the engine(s) are turned on  503  and the train power is provided by both engine(s) and the energy storage unit  504 . This operation can be continued until the SOC is reduced somewhat below A %. If the SOC of the energy storage system is greater than D %  505 , then train power is provided by the engines and the energy storage system may be used to provide additional propulsive power and/or auxiliary power  507  if additional SOC headroom is required, for example to make room for anticipated regenerative energy. If the SOC of the energy storage system is less than D % but greater than C % by an acceptable margin  506 , then train power is provided by the engines and the energy storage system may be used to provide additional propulsive power and/or auxiliary power  507  if additional SOC headroom is required. If the SOC of the energy storage system is less than an acceptable amount above C %  506 , then the train can proceed on engine power and excess engine power may be used to charge the energy storage system  508 . If the SOC of the energy storage system is less than anticipated future requirements, such as for example, an upcoming zero or low emissions zone, then the engines may be required to provide additional energy for charging. Once the train can proceed, the algorithm returns to the beginning of the cycle  509 . 
       FIG. 6  is an example of decision making for a hybrid locomotive in regenerative braking mode  601  and refers to  FIG. 2   b  or  2   c  for SOC references. This mode is typically used whenever the train or a section of the train is decelerating or descending a grade and the traction motors operating as generators are returning energy to the locomotive. If the SOC of the energy storage system is greater than A %  602  and if a full 100% charge  603  is not required, then all the braking energy is diverted to the resistive grids for dissipation  604 . If the SOC is not greater than A %  602  or a full charge is required  603 , then the energy from braking is sent to the energy storage system  605 . Whether braking energy is sent to the resistive grids  604  or to the energy storage system  605 , the train continues to brake with auxiliary power being provided by the engine(s) and, if needed, by the energy storage system  606 . Once the braking energy is allocated, the algorithm returns to the beginning of the cycle  609 . 
       FIG. 7  is an example of decision making for a hybrid locomotive maximum acceleration operating mode  701  and refers to  FIG. 2   b  or  2   c  for SOC references. If the SOC of the energy storage system is greater than D %  702 , then all engines are turned on to full power  702  and the energy storage system is also allowed to discharge at full power  703  so that the locomotive is at maximum available power. This mode may be required for exiting stations or accelerating to high speeds in a non-restricted portion of the route. If the SOC of the energy storage system is less than D %  702  but greater than C % by an acceptable margin  705 , then all engines and the energy storage system are turned on to full power  704 . If the SOC of the energy storage system is less than an acceptable amount above C %  705 , then the system can request operation at a lower power level  706 . If the request is acceptable, then the locomotive can proceed with all engines are turned on to full power and the energy storage system discharging at the highest power level that will avoid its SOC being reduced below C %  707 . If the request is not acceptable, then the locomotive must remain in its current mode (stopped or operating at reduced power), and the excess power capacity of the engine(s) used to charge the energy storage unit to an acceptable amount above C %  708 . Once the train can proceed, the algorithm returns to the beginning of the cycle  709 . 
     The present invention involves automatically managing a number of aspects of a hybrid locomotive in each zone or subzone of a known route such as for example a commuter or freight haulage route. A zone is a portion of the route over which one or more variables of the route are constant. Examples of such variables include but are not limited to train speed limit, noise and/or emission restrictions and the like. A zone may be subdivided into smaller subzones. 
     In a preferred embodiment of the present invention, an important objective is to manage the operation of the engines to comply with various environmental and regulatory restrictions while maximizing engine fuel efficiency, engine and energy storage apparatus lifetimes and minimizing operating costs. As will be shown, this management process is complex and not always suited to manual control. It is the objective of the present invention to disclose an automated hybrid locomotive engine, energy storage and environmental parameter management process that takes advantage of automated knowledge of the train&#39;s location at all times along a predetermined route using an on-board route map in conjunction with a locator which determines the locomotive&#39;s location and zone. 
     The following figures illustrate how energy may be allocated from engines, regenerative braking and external sources to an energy storage unit and how the engines and energy storage unit can be orchestrated to supply power for acceleration, auxiliary power, overcoming train resistances and ascending grades under varying environmental restrictions. These principles are applied with emphasis on controlling the operation of the engines to meet various requirements and minimize operating costs, both of which are essential to operating a rail service. 
     The requirements include but are not limited to the following:
         1. environmental restrictions which include emissions and noise. In general but not always, noise increases and decreases with increasing and decreasing emissions. Zones along the route may have emission restrictions, noise restrictions or combinations of these restrictions.   2. regulatory restrictions which include for example speed limits, mandatory stops and the like.
 
Operating costs include but are not limited to the following:
   1. fuel costs for the engines (affects operating costs). Since some energy is wasted charging an energy storage system, it is always preferable to use engine power directly for propulsion and auxiliary power when possible. Only when engine energy is being wasted is it preferable to route it to an energy storage unit. It is usually preferable to operate the engines in a mode that maximizes fuel efficiency.   2. lifetime of the engines (affects capital costs). Engine lifetime is reduced when the engines are run in peak power generating mode rather than in a lower power mode that, for example, maximizes fuel efficiency. However, it may be necessary to operate the engines at higher than optimum power or even at higher than rated power for short periods of time (typically no more than a few minutes) to achieve a desired acceleration and/or to ascend a grade and/or when auxiliary power demands are high (for example to power air-conditioning on a very hot day). Engine lifetime may also be affected by the decision to idle or turn off the engines when they are not required. It is preferable to idle the engines when engine power is not required so as to maintain oil pressure in the engine&#39;s oil galleries. If it is required to turn off the engines (for example to enter an underground station), then it may be necessary to have available pre- and post-lubricating pumps to keep engine components lubricated.   3. lifetime of energy storage apparatus (affects capital costs). For example, a battery pack lifetime can be reduced by overcharging such as by equalization charges or by deep discharges such as with overuse. Under some operating situations, it may be preferable to operate a battery pack between SOC limits typically in the range of 40% to 90%. To maintain the SOC in this preferred range, it is appropriate to leave room for charging by a regenerative braking system and to utilize the engines whenever the SOC is approaching the lower limit. Another factor in battery pack lifetime is maintaining a limit on the rate of discharge, for example when accelerating under combined engine and battery power. A battery pack can be discharged below its lower preferred limit or operated at high current discharge for brief periods when necessary. However, operating beyond the preferred limits, over time, does reduce battery pack lifetime.   4. component failure. In the example of a battery pack, sometimes battery units degrade or fail, resulting in a loss of energy storage capacity. When such failures are detected, then the hybrid power system can be modified to account for a change in storage capacity until the failing or failed units are replaced.       

     An example of a means by which requirements are met while minimizing costs is illustrated by reference to the following figures. 
       FIG. 8  shows an example of a typical velocity profile between two stations that corresponds to an engine power profile ( FIG. 9 ) and a battery pack power profile ( FIG. 10 ). The locomotive speed is zero when in the station  2411 . The train accelerates  2412  out of the station and reaches a constant velocity  2413 . After a period at constant velocity  2413 , the train then accelerates  2414  until it reaches a higher velocity  2415 . The train often but not always spends most of its station-to-station travel time at this high velocity  2415 . Eventually, the train decelerates  2416  until it reaches a lower velocity  2417 . After a period at constant velocity  2417 , the train then decelerates again  2418  until it comes to rest in the next station  2419 . 
       FIG. 9  shows an example of a possible profile of engine power usage between two commuter stations for the velocity profile discussed in  FIG. 8 . The engines are shown turned off and generating no power  2512  for the zones decelerating from high speed until entering the station, stopped at the station, leaving the station, accelerating to constant velocity and traveling at low speed. This profile would be applied, for example, if no noise or emissions are permitted in the vicinity of the station. When the train reaches the point where the engines can be turned on for acceleration to high speed, the engines are brought up to full power  2514  by a ramp-up  2513  which avoids turbo lag (turbo lag would result in heavy particulate and gas emissions in the case of diesel engines). Once the train has achieved high velocity, the engines are powered down to, for example, maximum fuel efficiency mode  2511  where they are operated to provide power for overcoming train resistances, auxiliary train power (also called hotel power) and, if needed, for charging the energy storage system (a battery pack in this example). When the train is ready to begin decelerating as it approaches the next station, the engines are turned off  2515 . Instead of turning the engines off, as in this example, the engines may be set to idle if low levels of noise and emissions are permitted in the vicinity of the station. 
       FIG. 10  shows an example of a possible profile of battery power between two commuter stations corresponding to the engine power profile of  FIG. 9  and velocity profile of  FIG. 8 . While the engines are shown turned off  2612  for the zones decelerating from high speed until entering the station, stopped at the station, leaving the station, accelerating to constant velocity and traveling at low speed, the batteries, when necessary, provide power for overcoming train resistances and providing auxiliary train power. As the train decelerates from high speed, the braking regeneration system charges the battery pack  2612 . During this period the battery pack may continue to supply auxiliary train power, even though net power output is negative  2612  because of the high power input from regenerative braking. As the train moves at lower constant velocity approaching the station, there is no regenerative braking and the battery power input is positive  2614  as it is providing power for overcoming train resistances and providing auxiliary train power. When the train decelerates into the station, the braking regeneration system again charges the battery pack  2622 . During this period the battery pack may continue to supply auxiliary train power, even though net power output is net negative  2622  because of the higher power input from regenerative braking. While in the station, train auxiliary power is provided by the battery pack. When the train accelerates out of the station in this example, it does so entirely with battery power  2613  to comply with environmental restrictions of no engine emissions or noise. When the train reaches a low constant velocity zone, battery power is reduced  2614  as it is only required to for overcoming train resistances and providing auxiliary train power. When the train is commanded to accelerate to high speed, both battery power  2623  and engine power ( 2514  in  FIG. 9 ) are high, providing maximum accelerating power to the train. In this example, when the train reaches its high constant velocity, the engines provide power for overcoming train resistances, providing auxiliary train power and charging the energy storage battery pack. Power output of the battery pack goes to zero and, because of charging by the engines, the net battery power is negative  2611 . 
       FIG. 11  illustrates the events of the engine and battery operation in relation to the velocity zones of  FIG. 8 . The velocity profile  2701  is shown below the profiles of engine power  2721  and battery power  2722  to further illustrate the locations along the route where the engine and batteries events occur in relation to one another. As an example, when the train accelerates to high velocity  2711 , both the engine power output  2704  and battery power output  2705  are turned on to maximum power. Battery power  2705  comes on-line almost instantly while engine power  2704  is ramped-up to reduce turbo-lag emissions. When the train is moving at high speed  2712 , the engines are supplying most of the power  2702  including sometimes charging the battery pack. During this phase of the route, the battery pack is not supplying power and is, in this example, absorbing power  2703  as some power from the engines is being used to charge the battery pack. 
       FIG. 12  shows the total power of the locomotive corresponding to the sum of the engine power profile of  FIG. 9  and battery power profile of  FIG. 10 . The engines are off and the train is operating on battery power only over the section of the route  2801  which, in this example, includes zones entering the station, at the station and leaving the station. When the train begins acceleration to high velocity, battery power output comes on-line almost instantly  2802  while engine power is ramped-up  2803 . Maximum locomotive power  2804  is achieved very quickly during this acceleration phase. Once the train has accelerated to a high speed zone, engine power is turned down to a much lower level  2805 , for example to maximum fuel efficiency mode, to provide power for overcoming train resistances, for auxiliary train power and for charging the battery pack. 
     The above power profiles may be modified in a number of ways depending on circumstances. For example, auxiliary train power may be turned down for portions of the route to allow more rapid charging of the battery pack, if necessary. If the train is ascending a grade, then battery power for propulsion may be used in zones where normally the battery pack is not being used or is being recharged. 
     As used in the descriptions of various embodiments of the present invention, zones (which may also be called segments) have been defined by the preceding examples, as velocity zones based on train speed regimes. For example, velocity zones discussed herein have included stopped, accelerating, constant velocity, decelerating zones. Zones can also be defined by other parameters such as, for example, zones where no engines are on, zones where only one engine is on, zones where more than one engine is on, zones where a certain range of engine power is used, zones where no emissions are allowed, zones where only a certain level of emissions are allowed, zones where emissions are unrestricted, zones where only a certain level of noise is allowed, zones where noise is unrestricted. 
       FIG. 13  is an-example of a flow chart of automated decision making for controlling engine operation in a zone or subzone that reflects measurements and decisions that might be made for the example as illustrated by  FIGS. 8 through 12 . This cycle of decisions depicted in  FIG. 13  can be executed continuously (for example every 1 second) or intermittently (for example every minute) or at intervals in between by a predetermined computer program or by a computer program that adapts, such as for example, a program based on neural network principles. After the cycle is initiated  2911 , the location of the train within the current zone or subzone is determined  2912  by means such as described previously. Then the SOC of the energy storage system is determined  2913  by means such as described previously. The capacity of the energy storage system is determined  2914  such as by measuring the voltages or integrated current history associated with the battery pack. Normally, energy storage capacity is approximately constant and very slowly changing over time. There are circumstances such as for example, failing battery units, failed battery units or slow degradation in overall battery pack capacity over time, that can cause energy storage capacity to change. When a change in capacity is detected  2915 , then the various control algorithms in the on-board computer program can be modified  2916  to reflect the change. When no change in capacity is detected  2915 , then the various control algorithms in the on-board computer program need not be modified. Next, any environmental parameter restrictions applicable to the current zone or subzone are determined  2917 . These include for example emissions, noise restrictions associated with operating the prime power engines. Next any regulatory restrictions applicable to the current zone or subzone are determined  2918 . These include for example speed limits, caution zones and the like required by the railroad. Next, braking requirements applicable to the current zone or subzone are determined  2919 . These include for example zones of deceleration and down grades along the current zone or subzone of the route. Once the braking requirements are determined  2919 , the amount of energy that can be recovered by braking can be computed  2920 . Once, the state of the energy storage system, environmental, regulatory and braking variables are determined for the current zone or subzone, then a trial operational profile for operating the engines  2921  can be computed for the current zone or subzone. Computing the implementation of this profile can be undertaken to estimate the SOC of the energy storage unit  2922  as the train progresses through the current zone or subzone. If the estimated SOC is projected to fall outside the preferred limits of energy storage unit operation, then the operational profile for operating the engines can be modified  2923 , unless exceptions override this potential modification. Such exceptions can be for example, a steep uphill grade that must be negotiated where battery SOC may have to be allowed to fall below the preferred lower limit. If the estimated SOC is projected to fall within the preferred limits of energy storage unit operation, then the trial operational profile for operating the engines  2921  need not be modified. Next, the computer control program can query its database  2924  to compare the trial operational profile for operating the engines with prior operating profiles for the current zone or subzone. The comparison can be made, for example, by progressively narrowing the prior profiles on the basis of descriptors associated with the profiles. For example, prior profiles where the temperature, precipitation, wind and rail conditions are similar would be given a higher weighting than those with significantly different weather or rail conditions. Additionally, prior profiles could be adjusted for number of commuter cars in the train consist and even for passenger load. This process  2925  can be used to adjust  2926 , if necessary, the profile for the current zone to ensure that the current profile is adjusted for variables (descriptors) such as outside temperature, precipitation, and wind conditions, passenger load and the like, and is reasonable in light of comparison with prior profiles from the same zone. As part of this process, the hybrid locomotive may be provided with a device for determining outside weather, in addition to its location, at all times and at all locations along its intended route. If such adjustments are warranted based on past similar profiles, the engines may be programmed to provide more or less charging of the energy storage units, more or less auxiliary power to the commuter cars and any other modifications that may be necessary to further optimize the engine operating profile. If there are no substantial profile adjustments dictated by comparison  2925  with previous profiles, then the operational profile for operating the engines need not be modified. Finally, the computer control program can “look ahead”  2927  to determine if any significant events are about to be encountered in subsequent zones that might modify the operational profile for operating the engines. Such events may be for example, long tunnels where engines must be turned off, long uphill grades requiring additional battery power or long downhill grades requiring substantial battery capacity to absorb regeneration energy. If such events are identified  2928 , they may require modifying the operational profile for operating the engines  2929 . For example, the engines may be programmed to provide additional charging of the energy storage unit if a long tunnel and/or a long uphill grade will be encountered in a subsequent zone or subzone. Alternately, the engines may be programmed to provide less charging of the energy storage unit if a downhill grade will be encountered in a subsequent zone or subzone and substantial regeneration energy is expected to be available for charging the energy storage unit. If there are no substantial events identified in the “look ahead”, then the operational profile for operating the engines need not be modified and the final operational profile for operating the engines can be stored in the data base  2930  for future use. Thereupon, the decision cycle can be completed  2931 . 
     The present invention is further illustrated by an example of a hybrid locomotive and commuter cars operating over a typical rail commuter route in a large urban area which may be comprised of a number of separate cities and towns. In this example, a hybrid locomotive is used to pull several air-conditioned (or heated depending on the season) commuter cars on a round trip between two terminus stations. The route has a no net elevation change but does have a significant elevation change between the terminus stations. The route includes a portion near one terminus where the line passes through a long tunnel which is too small to permit the use of internal combustion engines. The train has a regenerative braking system that can recover much of the kinetic energy of the train when decelerating or when descending a grade. The energy required for air-conditioning, other auxiliary power requirements and for various losses such as rail friction, flange friction on curves and wind resistance etcetera is irrecoverable. 
     In an emissions strategy, it is desired to make the best use of available energy-generating sources. These include:
         on-board engines which, when in operation, produce emissions   regenerative braking systems which recapture energy used previously to accelerate the train   external energy sources which include:
           third electrified rails (emissions generated elsewhere)   overhead catenaries (emissions generated elsewhere)   railside generators which, when in operation, produce emissions   railside energy storage units which obtain their energy from various sources including regenerative braking energy delivered from prior locomotives that have exceeded their on-board energy storage capacity (no emissions produced)   rail side connections into a power grid (emissions generated elsewhere)   
               

     It is an important that some or all of the above external energy-generating sources be part of the energy resources available to the hybrid locomotives of the of the present invention. This is because a number of these external energy-generating sources produce emissions in locations far removed from the operational territory of the locomotive of the present invention and therefore do not contribute emissions to the operational territory of the locomotive and train where emissions requirements may be in force. 
     The principal train parameters for this example are given in the following tables. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Train 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Total Train Mass (tons) 
                 700 
               
               
                   
                 Number of Locomotives 
                 1 
               
               
                   
                 Number of Commuter Cars 
                 10 
               
               
                   
                 Air Conditioning (kW per car) 
                 20 
               
               
                   
                 Draw Bar Power of Locomotive (HP) 
                 3,500 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 Battery Pack 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Maximum Allowable Current (A) 
                 1,250 
               
               
                 Maximum Draw Bar Power Rating (HP) 
                 1,400 
               
               
                 Capacity Rating (kW-hrs) 
                 1,440 
               
               
                 Cell Configuration 
                 450 each 2.1 volt cells in series 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Engines and Efficiencies 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Total Engine Draw Bar Power Rating 
                 2,060 
               
               
                   
                 (HP) 
               
               
                   
                 Battery Charging Efficiency 
                   95% 
               
               
                   
                 Drive Train Efficiency 
                   94% 
               
               
                   
                 Regenerative Braking Recovery Efficiency 
                   85% 
               
               
                   
                   
               
             
          
         
       
     
     In the above scenario, the train is stopped at the originating terminus station (station A) for 5 minutes, at intermediate stations for 1 or 2 minutes, and at the destination terminus station (station B) for 5 minutes. The train accelerates out of all stations on engine and battery to a low velocity and maintains this speed for a short distance. The train then accelerates to its maximum speed again using both engine and battery power until the high speed portion of the route. This high speed is maintained primarily on engine power. The engines are then idled or turned off until the train decelerates by braking and enters a low speed zone approaching the next station. The train maintains this lower speed for a short distance then decelerates by braking to a stop at the next station. In this example, the engines are always turned off while decelerating into a station and while stopped in the station. In this example, the engines are not used to charge the energy storage battery pack. 
     In this example, there is a long tunnel and a down grade before the train enters an underground station which is the destination terminus station. The engines must be turned off in the tunnel and in the underground station. On the return trip, the train must leave the station and ascend the grade in the tunnel, again with the engines turned off. 
     In this example, energy is returned to the energy storage unit by regenerative braking and by recharging from an external source at terminus station A at the end of a commuting cycle. There is no energy returned to the energy storage system by the engines. This is an example of a low emissions operating strategy over most of the route and a zero emissions operating strategy over a substantial portion of the route. 
     The elevation profile of the route and location of the tunnel shown in  FIG. 14 . The route begins at terminus station A  1402  and arrives at terminus station B  1403  over a distance of 29 miles. The round trip back to terminus station A  1402  is thus 58 miles. In this example, the route has an elevation change  1401  near the destination terminus station where the grade rises approximately 160 feet then returns to approximately its original value  1403 . The net elevation change between the originating terminus station and the destination terminus station is approximately zero such as would be the case, for example, if the terminus stations were both at sea level. In this example, the locomotive can recover energy from a regenerative braking system when it is used during deceleration into stations or used to control speed going down grade. 
     The velocity profile of the route is shown in  FIG. 15  which shows the locations of the two terminus station A  1502  and station B  1503  and the  11  intermediate stations  1504 . The velocity profiles from the originating terminus station  1502  to the destination terminus station  1503  are identical, being a mirror images, to the velocity profiles for the return leg from station  1503  to station  1502 . The form of the velocity profiles between each station are all similar except for the route segment  1505  which is too short for the train to accelerate to a high velocity zone. Between most stations there is a zone leaving the station of acceleration to low velocity  1511 , a zone of constant speed at low velocity  1512 , a zone of acceleration to high velocity  1513 , a zone of constant speed at high velocity  1514 , a zone of deceleration to low velocity  1515 , a zone of constant speed at low velocity  1516 , and finally a zone of deceleration to a stop  1517  in the next station. 
     These route parameters and velocity/acceleration conditions are for illustrative purposes only. They serve to illustrate how energy is typically managed for emissions control between the locomotive engines and its energy storage system. 
       FIG. 16  is a schematic representation of a typical velocity  1601  versus distance  1602  profile and engine operating mode zones  1602  associated with two intermediate stations  1604  and  1612 . The velocity profile is comprised of the following zones which are meant to be illustrative examples.
         in the station  1604     accelerating to low velocity  1605     constant speed at low velocity  1606     acceleration to high velocity  1607     constant speed at high velocity  1608     decelerating to low velocity  1609     constant speed at low velocity  1610     decelerating to a stop in a station  1611     in the next station  1612         
     The structure of the various engine operating mode zones  1602  shows when the engines are idled or turned off, turned on to boost acceleration, turned on to maintain constant speed at near optimum fuel economy and idled or turned off when braking. In this example, each engine operating mode zone corresponds to a zone in the velocity profile. The engines are idled or turned off in zones  1622  and  1630  which are the velocity zones in the stations  1604  and  1612 . The engines are idled or turned off in zones  1621 ,  1627  and  1629  which correspond to deceleration velocity zones  1603 ,  1609  and  1611  (braking). The engines are operated at or near maximum fuel economy in zones  1624 ,  1626  and  1628  which are the constant velocity zones  1606 ,  1608  and  1610 . The engines are turned on to at or near full power in acceleration zones  1623 ,  1625  and  1631  which are the velocity zones where the train accelerates to low velocity  1605  and where the train accelerates to high velocity  1607 . Some of the engines may be turned off in the high speed zone  1608 . In this zone, the engines may be turned off when the power required is below a predetermined level and/or the train is descending a grade and using the regenerative braking system to control speed and charge the batteries without engine emissions. 
     The structure of the various engine operating mode zones  1705  and velocity zones for the destination terminus station (station B) for this example are illustrated in  FIG. 17  which shows when the engines are turned off in the tunnel and underground station, turned on to boost acceleration, turned on to maintain constant speed at near optimum fuel economy and idled or turned off when braking. In addition, the location of a tunnel  1701  and an underground portion  1702  of the terminus station are shown. In this example, the train leaves the last intermediate station and descends a grade as it passes through the tunnel towards the terminus station B. When the train leaves terminus station B, it ascends the grade as it passes through the tunnel towards the intermediate station it last visited. 
     The velocity profile  1706  is comprised of the following zones which are meant to be illustrative examples.
         in the last intermediate station  1753     accelerating to low velocity  1756     constant speed at low velocity  1757     acceleration to high velocity  1758     constant speed at high velocity  1759     decelerating to low velocity  1760     constant speed at low velocity  1761     decelerating to a stop in terminus station B  1755     in terminus station B  1754         

     The engines are turned off in engine operating mode zones  1725  through  1735  which are the engine operating mode zones in the tunnel  1701 , between the tunnel  1701  and the underground station  1702  and in the underground station  1702 . The engines are turned on to boost acceleration in engine operating mode zones  1723  and  1739  which are acceleration velocity zones  1756  out of station  1754  and  1753 . The engines are idled or turned off in engine operating mode zones  1722  and  1738  which are the velocity zones in the station  1753 . The engines are idled or turned off in engine operating mode zones  1721  and  1737  which correspond to deceleration velocity zones  1755  (braking). The engines are operated at or near maximum fuel economy in engine operating mode zones  1724 ,  1736  and  1740  which are the constant low velocity zones  1757  and  1761 . 
     While the engines are turned off in engine operating mode zones  1725  through  1735 , all of the train energy is provided solely by the energy storage system. While the train is stopped in the underground station  1702 , the energy storage system can be partially or fully recharged by plugging into an external source such as a local power grid. In the present example, this was not necessary. As the train leaves the terminus station  1754  to return to station  1753 , it ascends the grade inside tunnel  1701  under battery power only. This is the most taxing part of the route for the battery pack. 
     In this example, the engines are used for boosting acceleration and providing some of the auxiliary power to the train, and providing propulsion power for ascending grades and operating over the high speed portions of the route. As noted above, the engines are turned off completely over the portion of the route in the tunnel to terminus station B and back through the tunnel. 
     The engines are not used to recharge the energy storage system. The energy storage system is used to provide most of the auxiliary power to the train. This is not the most energy efficient operation but it is the most emissions efficient operation. The energy inefficiency is absorbed by the local power grid charging system at the end of the commuter cycle in terminus station A and the emissions associated with this are generated elsewhere, outside the operating territory of the train. This operating strategy requires less use of the engines inside the operating territory of the train. 
     The average locomotive engine power over the route is less than 500 HP which is well below the rated engine power of the locomotive (2,000 HP in this example).  FIG. 16  shows the amounts of energy delivered by the prime energy source  1801  and the energy storage unit  1802  for various purposes for the closed loop route from station A to station B and then returning to station A. None of the engine energy is used for charging  1815  the energy storage unit. Approximately equal amounts of the energy produced by the engines is used to boost locomotive acceleration  1811  and to overcome train resistances  1812 . Lesser amounts of engine energy are used for providing auxiliary power  1813  and ascending grade  1814 . The energy storage unit (a battery pack in this example) supplies most of its energy to provide acceleration  1821  and then to supply auxiliary power  1822 . The energy storage system provides some of the energy  1822  to overcome train resistances and ascending grade  1824 . The sum of energy dispensed by the battery pack is considerably greater than the energy provided by the engines. The difference is made up by the energy received from the external power grid at terminus station A at the end of a route cycle. 
       FIG. 19  shows the sources of energy inputs  1901  to energy storage unit and energy outputs  1902  by the energy storage unit for the closed loop commuter route from station A to station B and then returning to station A. In general, the total inputs  1924  should be close to equaling the total outputs  1916  to restore the SOC of the battery to approximately to its starting value. In this example, which employs a low emissions operating strategy, there are no inputs from the engines  1921 . The primary input of energy is from the regenerative braking system  1922 . At the end of a route cycle, the energy needed to restore the battery to its desired SOC is provided by an external source  1923  such as for example a plug into a local power grid at terminus station A. The output sinks of energy from the energy storage unit are to accelerate the train  1911 , to provide auxiliary power  1913 , to overcome train resistances  1912 , to ascend grade  1914  and to account for internal resistive losses  1915  from the energy storage unit. When operating in a low emissions mode and not utilizing the engines to recharge the energy storage system, an external source of energy input  1923  will always be needed. This is because braking energy cannot be fully recovered and energy supplied for auxiliary train power, overcoming train resistances and battery I 2 R losses are unrecoverable. 
     As can be appreciated, there are other operating strategies that can further reduce emissions, such as for example, operating the engines only for boosting acceleration. These strategies are typically not the best energy management strategies from a fuel consumption perspective but they may be mandated in areas of high pollution. 
     It is also noted that operating on the energy storage system with minimal engine usage, results in lower noise, since the principal source of this is from the engines, especially from large engines. 
       FIG. 20  shows the SOC  2001  of energy storage system versus distance  2002  over the commuter route which begins at the originating terminus station  2005 , continues to the destination terminus station  2006  and then returns to the originating terminus station  2005 . The SOC is initially about 90%  2007  in this example, and slowly declines to about 75%  2008  as the train reaches the destination terminus station  2006 , benefitting from charging by the regenerative braking system as it descends the grade into the terminus station  2006 . In this example, the SOC drops to a low of 60%  2009  after the train has left the terminus station  2006 , has ascended the grade in the tunnel and has emerged from the tunnel under battery power only. Once the train returns to the level portion of the route, the SOC slowly declines to approximately 50%  2010  as the train arrives at the originating terminus station  2005 . The SOC of the energy storage unit is then returned to its desired starting value of approximately 90%  2011  by being recharged from an external source. The requirement to operate on battery only while in the tunnel and the destination terminus station  2006 , dictates the size of the battery and engines more than any other single factor in this example. The engines operate at about 25% of their capacity over the full route. In this example, the battery throughput is approximately 2,700 ampere-hours which is a small portion of its expected lifetime. 
     The following embodiments, involve operating a consist of locomotives, at least one of which is a hybrid locomotive. An important feature of these embodiments is that the consist must have the ability to operate in emissions free mode over a significant portion of its route such as for example a long tunnel or an underground station where the train must stop for a reasonable period of time. 
       FIG. 21  is a schematic side view of an example of a consist of hybrid locomotives. A locomotive consist may be comprised of two or more locomotive types, including at least one or more locomotives which are fully independent, one or more cabless hybrids serving as B-units, one or more energy storage tender cars. Members of the consist need not be adjacent to one another and can be located anywhere in the train. As an example, the consist shown in  FIG. 21  is comprised of an independent hybrid locomotive  2101  and two cabless hybrid locomotives  2102 . 
     In a first consist embodiment, at least two of a hybrid locomotive and energy tender car can form a locomotive consist where the operation of each hybrid locomotive and energy tender car has the autonomous ability to operate in all the operational and environmental states described above. As can be appreciated, a lead locomotive is typically used for issuing power and braking commands to all the consist members, otherwise each member manages its own operational and environmental states described above. This embodiment might be preferred, for example, if all members of the consist have same configurations of hybrid locomotives and energy storage tender cars. In this embodiment, all of the members of the consist must have a regenerative braking system since they all must act autonomously. 
     In a second consist embodiment, at least two of a hybrid locomotive and energy tender car can form a locomotive consist where the operation of all of the members of the consist is co-ordinated to maximize the effectiveness of the operational and environmental states described above, by a master controller in communication with all the members of the consist. This embodiment might be preferred, for example, if various members of the consist have differing configurations of hybrid locomotives and energy storage tender cars. In this embodiment, all of the members of the consist must have a regenerative braking system since they all must be able to supply enough energy to operate in emissions free mode for a substantial portion of the route. 
     In a third consist embodiment, at least two of a hybrid locomotive and energy tender car can form a locomotive consist where the operation of all of the members of the consist is co-ordinated to maximize the effectiveness of the operational and environmental states described above, by a master controller in communication with all the members of the consist and with the ability to allocate energy between the various members of the consist. This latter feature means that consist members are interconnected by a direct current power bus for exchanging electrical energy. This embodiment is most preferred for all configurations of hybrid locomotives and energy storage tender cars since imbalances in energy storage between members can be corrected. In this embodiment, at least one of the members of the consist must have a regenerative braking system, although it is preferred that most of the consist members have a regenerative braking system. 
     In a fourth consist embodiment, a method is provided for managing the environmental states of a consist of locomotives where at least one of the members of the consist is a hybrid locomotive and wherein the consist can be operated at low emissions or zero emissions mode over a substantial portion of its route. In this embodiment, the non-hybrid members of the consist may be required to be idled (low emissions mode) or to be turned off (zero emissions mode) for a required substantial portion of the route. The consist is managed by a master controller in the lead hybrid locomotive and is in communication with all the members of the consist. This embodiment is applicable for consists which may contain non-hybrid members such as conventional diesel-electric or diesel-hydraulic locomotives. If consist members are interconnected by a direct current power bus for exchanging electrical energy, then the master controller may have the ability to allocate energy between the various members of the consist. This would include being able to transfer energy to or from the traction motors of the non-hybrid members of the consist. 
     In another embodiment, at least two of a hybrid locomotive and energy tender car can form a part of a locomotive consist having one or more independently controllable features. These independently controllable features may include, for example, the total amount of tractive effort applied, the operation of the prime power sources, the amount of stored energy used, the amount of power applied by either or both of the prime power sources and energy storage systems, control of wheel slip, control of wheel skid, amount of regenerative braking energy stored and amount of energy, if any, transferred to other locomotives in the consist. Independent control of features such as described above can be effected by predetermined or programmable logic in an on-board programmable logic controller, a microcomputer, an industrial computer or the like. Control may also be accomplished for each member in the consist from the lead hybrid locomotive, or from the lead hybrid locomotive to the adjacent hybrid locomotive and then daisy-chained from each neighboring member of the consist to the next utilizing predetermined or programmable logic in on-board programmable logic controllers, microcomputers, industrial computers or the like. Control may be by any number of communication methods such as for example, by hard wire from locomotive to locomotive, radio telemetry, other forms of wireless communication, and/or audio and/or video linkage telemetry. 
     In a preferred embodiment, a method is provided for managing the environmental states of a hybrid locomotive or consist of hybrid locomotives. The consist members can be any energy consuming and/or providing vehicles, such as a hybrid locomotive, a cabless hybrid locomotive, an energy storage tender car, and the like. In this configuration, at least one of the members is a hybrid locomotive including an energy storage unit for storing electrical energy, an engine for providing electrical energy to the energy storage unit or its traction motors and a regenerative braking system for some or all of its electrical energy to the energy storage unit. The consist members are interconnected by a communications link and may also be interconnected by a direct current power bus for exchanging electrical energy. 
     The method for controlling the energy allocations in a hybrid consist member was disclosed in U.S. patent application Ser. No. 11/070,848. 
     A number of variations and modifications of the invention can be used. As will be appreciated, it would be possible to provide for some features of the invention without providing others. For example, in one alternative embodiment, the various inventive features are applied to vehicles other than locomotives, such as cars, railroad cars, and trucks. The control logic set forth above may be implemented as a logic circuit, software, or as a combination of the two. 
     The present invention, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, sub-combinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, for example for improving performance, achieving ease and/or reducing cost of implementation. 
     The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention. 
     Moreover though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.