Patent Publication Number: US-2021170873-A1

Title: Power supply systems and methods for vehicles

Description:
RELATED APPLICATIONS 
     This application (Attorney&#39;s Ref. No. P219723us) is a 371 of International PCT Application No. PCT/US2019/035444, currently pending. 
     International PCT Application No. PCT/US2019/035444 claims benefit of U.S. Provisional Application Ser. No. 62/680,485 filed Jun. 4, 2018, now expired. 
     The contents of all related applications are incorporated herein by reference. 
    
    
     BACKGROUND 
     The present application relates to power supply systems and methods and, in particular, to power supply systems and methods adapted for use on vehicles. 
     Utility power is typically made available as an AC power signal distributed from one or more centralized sources to end users over a power distribution network. However, utility power is unavailable for certain structures. For example, movable structures such vehicles do not have access to utility power when moving and can be connected to the utility power distribution network when parked only with difficulty. Similarly, remote structures such as cabins and military installations not near the utility power distribution network often cannot be practically powered using utility power. 
     DC power systems including batteries are often employed to provide power when utility power is unavailable. For example, trucks and boats typically employ a DC power system including a battery array to provide power at least to secondary vehicle electronics systems such as communications systems, navigation systems, ignition systems, heating and cooling systems, and the like. Shipping containers and remote cabins that operate using alternative primary power sources such as solar panels or generators also may include DC power systems including a battery or array of batteries to operate electronics systems when primary power is unavailable. Accordingly, most modern vehicles and remote structures use battery power sufficient to operate, at least for a limited period of time, electronics systems such as secondary vehicle electronics systems. 
     The capacity of a battery system used by a vehicle or remote structure is typically limited by factors such as size, weight, and cost. For example, a vehicle with an internal combustion engine may include a relatively small battery to start the engine and/or for use when the engine is not operating. A large battery array may be impractical for vehicles with an internal combustion engine because the size of the batteries takes up valuable space and the weight of the batteries reduces vehicle efficiency when the vehicle is being moved by the engine. All electric vehicles have significantly greater battery capacity, but that battery capacity is often considered essential for the primary purpose of moving the vehicle, so the amount of battery capacity that can be dedicated to secondary vehicle electronics systems is limited. Battery systems employed by remote structures must be capable of providing power when the alternative power source is unavailable, but factors such as cost, size, and weight reduce the overall power storage capacity of such systems. 
     Heating and cooling systems have substantial energy requirements. Vehicles such as trucks or boats typically rely on the availability of the internal combustion engine when heating or cooling is required. When heating or cooling is required when the vehicle is parked (or the boat is moored) for more than a couple of minutes, the internal combustion engine will be operated in an idle mode solely to provide power to the heating and cooling system. Engine idling is inefficient and creates unnecessary pollution, and anti-idling laws are being enacted to prevent the use of idling engines, especially in congested environments like cities, truck stops, and harbors. For remote structures such as cabins or shipping containers, heating and cooling systems can be a major draw on battery power. Typically, an alternative or inferior heating or cooling source such as a wood burning stove, fans, or the like are used instead of a DC powered heating and cooling system. 
     The need thus exists for power supply systems and methods capable of augmenting battery power in a vehicle or remote structure. 
     SUMMARY 
     The present invention may be embodied as a vehicle comprising a motor, a power supply, a load, and a fuel system. The power supply system comprises a DC bus, a turbine generator operatively connected to the DC bus, and a battery system operatively connected to the DC bus. The load is operatively connected to the DC bus. The fuel system supplies fuel to the motor and the turbine generator. The turbine generator supplies a power signal to the DC bus based on fuel from the fuel system. The motor operates based on fuel from the fuel system. 
     The present invention may also be embodied as a power supply system for a vehicle comprising a motor, a load, a fuel tank, and a primary fuel line for supplying fuel from the fuel tank to the motor, the power supply system comprising a DC bus, a turbine generator, and a battery system. The DC bus is operatively connected to the load. The turbine generator is operatively connected to the DC bus. The battery system is operatively connected to the DC bus. The turbine generator supplies a power signal to the DC bus based on fuel from the fuel system. 
     The present invention may also be embodied as a method of forming a vehicle comprising the following steps. A motor and a fuel tank are supported on a frame. A power supply system comprising a DC bus, a turbine generator operatively connected to the DC bus, and a battery system operatively connected to the DC bus are provided. A load is operatively connected to the DC bus. Fuel from is supplied from the fuel tank to the motor. Fuel is supplied from the fuel tank to the turbine generator. The turbine generator is operated to supply a power signal to the DC bus based on fuel supplied to the turbine generator from the fuel tank. The motor is operated based on fuel from the fuel system. 
     The present invention may also be embodied as a method of supplying electrical power to a vehicle comprising a motor, a load, a fuel tank, and a primary fuel line for supplying fuel from the fuel tank to the motor comprising the following steps. A DC bus is operatively connected to the load. A turbine generator is operatively connected to the DC bus. A battery system is operatively connected to the DC bus. The turbine generator operated to supply a power signal to the DC bus based on fuel from the fuel system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevation view of an example vehicle employing a first example power supply system of the present invention; and 
         FIG. 2  is a block diagram illustrating the interaction of the first example power supply system with the example vehicle of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1 and 2  of the drawing depict an example vehicle  20  on which is mounted a first example power supply system  22 . As shown in  FIG. 2 , the example power supply system  22  comprises a turbine generator system  30  defining positive and negative terminals  32  and  34 , a battery system  40  defining positive and negative terminals  42  and  44 , and a DC bus  50  comprising a first bus connector  52  and a second bus connector  54 . The positive terminals  32  and  42  are electrically connected to the first bus conductor  52 , and the negative terminals  34  and  44  are electrically connected to the second bus connector  54 . 
     The example vehicle  20  is or may be conventional and comprises a frame  60 , wheels  62 , a cab  64 , and an engine compartment  66 . The wheels  62  are rotatably supported by the frame  60 . The cab  64  is rigidly supported by the frame  60  when the vehicle  20  is moving. The example turbine generator system  30  is typically supported by the frame  60  outside of the cab  64 . The example battery system  40  is typically located within the cab  64  and/or the engine compartment  66 . 
     The example vehicle  20  further comprises a motor system  70  comprising a motor  72  and motor electronics  74 . The motor  72  is mechanically connected to at least one of the wheels  62  such that operation of the motor  72  rotates at least one of the wheels  62  to propel the vehicle  20 . The motor electronics  74  are operatively connected to the DC bus  50 . Typically, the motor electronics  74  will include control devices (not shown) such as sensors, microprocessors, and actuators and an alternator (not shown) configured to supply power to the DC bus  50  when the motor  72  is running. 
     The example vehicle  20  further operatively comprises a fuel system  80  comprising a fuel tank  82 , a main fuel line  84 , and a secondary fuel line  86 . The main fuel line  84  allows fuel to flow from the fuel tank  82  to the motor  72 , while the secondary fuel line  86  allows fuel to flow from the fuel tank  82  to the turbine generator system  30 . The fuel system  80  will typically further include control devices such as pumps, valves, and sensors (not shown) configured to ensure that an adequate amount of fuel is delivered to the motor  72  and/or the turbine generator system  30  as appropriate. The example fuel tank  82  is typically supported by the frame  60  outside of the cab  64 . 
       FIGS. 1 and 2  further illustrate that the example vehicle  22  further comprises cab electronics  90  and a heating/cooling system  92 . The example cab electronics  90  includes electronics not integral to the functioning of the motor system  70 , such as communications equipment, audio/visual equipment, and navigation equipment. The example heating/cooling system  92  comprises a compressor and condenser (not shown) and associated conduits and controls capable of heating and/or cooling the cab  64  of the vehicle  22 . The cab electronics  90  and the heating/cooling system  92  are typically mounted partly within and partly outside of the cab  64 . 
     As shown and described above, the turbine generator system  30  is configured to generate a DC signal across the positive terminal  32  and negative terminal  34  based on fuel flowing from the fuel tank  82  through the secondary fuel line  86 . The positive terminal  32  and negative terminal  34  are in turn connected to the first and second conductors  52  and  54 , respectively, of the DC bus  50 . The turbine generator system  30  thus creates a DC power signal capable of providing power to electronics operatively connected to the DC bus  50 . Typically, the DC power signal generated by the turbine generator system  30  is used to charge the battery system  40  and/or supply power to any one, two, or all of the motor electronics  74 , the cab electronics  90 , and the heat/cool system  92 . 
     Typically, the turbine generator system  30  will generate the DC power signal when operation of the motor system  70  is undesirable. For example, when the example vehicle  20  is parked, the motor system  70  is typically switched off (e.g., to conform to anti-idling laws) and the turbine generator system  30  will be turned on such that the DC power signal is present on the DC bus allowing the heating/cooling system  92  to heat or cool the cab  64  and or the operator to have access to the cab electronics. The turbine generator system  30  is also capable of charging the battery system  40  with the motor system  70  switched off. 
     The present invention is of particular significance when the fuel system  80  is configured to store and supply diesel fuel to the motor system  70 . In this case, the turbine generator system  30  is configured to operate using diesel fuel stored in the fuel system  80  to obviate the need for a separate source of fuel for the turbine generator system  30 . 
     The example turbine generator system  30  includes both a turbine generator (not shown) and a rectifier (not shown) for converting the alternating current output of the turbine generator into a DC power signal appropriate for the DC bus  50 . Accordingly, the example turbine generator system  30  generates a DC power signal directly applicable to the DC bus  50  to which the battery system  40 , motor electronics  74 , cab electronics  90 , and/or heat/cool system  92  are connected. Alternatively, one or more DC-DC converters may be employed to alter (increase or decrease) the DC voltages from the voltage on the DC bus  50 . 
     Further, some vehicle electronics (e.g., brushless motor) may require an AC input. For example, the heat/cool system  92  may incorporate a brushless motor that operates based on an AC power signal. Typically, the brushless motor incorporates a driver (not shown) that converts a DC power signal into an appropriate AC power signal. Alternatively, a driver incorporating a DC-AC converter may be arranged between the DC bus  50  and the AC vehicle electronics. As yet another alternative, the turbine generator and AC vehicle electronics may be configured so that the AC output of the turbine generator is directly applicable to the AC vehicle electronics without conversion to DC, effectively bypassing the DC bus  50 .