Patent Publication Number: US-2006006007-A1

Title: System and method for providing electrical power to a vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application claims priority on U.S. Provisional Patent Application Ser. No. 60/585,642, for System and Method for Providing Electrical Power to a Vehicle, filed on Jul. 7, 2004, the entirety of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates to a system and method for providing electrical power. In particular, the present invention is directed to a system and method for providing electrical power onboard a vehicle. Embodiments of the present invention may be used to power electronic devices onboard a heavy-duty truck.  
     BACKGROUND OF THE INVENTION  
      Heavy-duty truck drivers are known to keep their trucks running at an idle while the trucks are not moving, for example, at rest stops. This is often done in order to provide power for the many electrical devices that may be found on-board the vehicle. If the truck is not running, available power is often drawn from the vehicle&#39;s battery, thereby depleting the battery.  
      In addition, the amount of electrical power available from the battery may not supply the truck with enough electricity to power all of the necessary or desired electrical components. Thus, to provide the necessary amount of electric power, truck drivers often run their trucks at an idle while at rest stops. This process, however, can lead to many drawbacks, including increased cost, unnecessary fuel consumption, increased pollution, and noise.  
      Many truck stops, in an effort to reduce the number of idling vehicles in light of the above detriments, may provide 120 volt or 240 volt power hook-ups for providing electrical power to the vehicles. In order to take advantage of these hook-ups, however, vehicles may require after-market inverters and/or chargers. These additional components can lead to increases in the cost of installation and use. In addition, many known after-market components generally have a continuous power output of only 1 kW. This amount of continuous power may not be enough to power all of the electrical components that are necessary and/or desired.  
      The systems and methods of the present invention may provide electrical power onboard a vehicle. Some, but not necessarily all, embodiments of the present invention may provide an inexpensive device to provide electrical power to a truck while at rest, in order to power necessary and desired electrical components without running the truck at idle. Some, but not necessarily all, embodiments of the present invention may provide a device that may enable heavy-duty trucks to take advantage of electrical hook-ups presently available at truck stops, by connecting their onboard electrical loads to such external power supplies. Some, but not necessarily all, embodiments of the present invention may provide a device that will provide a high enough continuous power output in order to power all necessary and desired electrical components. Some, but not necessarily all, embodiments of the present invention may be installed on a heavy-duty truck during its production for only a small increase in cost.  
      Additional advantages of embodiments of the invention are set forth, in part, in the description which follows and, in part, will be apparent to one of ordinary skill in the art from the description and/or from the practice of the invention.  
     SUMMARY OF THE INVENTION  
      Applicant has developed innovative systems and methods for providing electrical power onboard a vehicle. In one embodiment, the system comprises: an AC/DC converter; a power supply connected to the AC/DC converter so as to provide an input to the AC/DC converter; a cable connected at one end to the power supply and at the other end to the AC/DC converter so as to provide an electrical power from the external power source as an input to the AC/DC converter; and a controller, connected to the AC/DC converter and controlling various parameters of the selected power supply.  
      Applicant has further developed a system for providing electrical power onboard a vehicle, the system comprising: an AC/DC converter; an onboard power supply connected to the AC/DC converter so as to provide an input to the AC/DC converter; an external power source; a cable connected at one end to the external power source and at the other end to the AC/DC converter so as to provide electrical power from the external power source as an input to the AC/DC converter; at least one AC load; a DC/AC converter, connected so as to receive inputs from the AC/DC converter, convert the electrical power to a desired phase and magnitude, and send outputs to the AC load; at least one DC load; a DC/DC converter, connected so as to receive inputs from the AC/DC converter, convert the electrical power to a desired phase and magnitude, and send outputs to the DC load; and a controller, connected to the AC/DC converter and controlling various parameters of the selected power supply.  
      It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated herein by reference, and which constitute a part of the specification, illustrate certain embodiments of the present invention and, together with the detailed description, serve to explain the basic principles of the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      In order to assist in the understanding of the present invention, reference will be made to the appended drawings, in which like reference characters refer to like elements. The drawings are exemplary only, and should not be construed as limiting the invention.  
       FIG. 1  is a block diagram of a starter/alternator power supply system in accordance with a first embodiment of the present invention.  
       FIG. 2  is a block diagram of a starter/alternator power supply system in accordance with a second embodiment of the present invention.  
       FIG. 3  is a block diagram of a starter/alternator power supply system in accordance with a third embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION  
      Reference will now be made in detail to embodiments of the system and method of the present invention, examples of which are illustrated in the accompanying drawings. As embodied herein, the present invention comprises systems and methods of providing electrical power to one or more systems and loads onboard a vehicle.  
       FIG. 1  illustrates a first embodiment of a system  10  for providing electrical power to one or more loads onboard a vehicle. The system  10  may comprise a power system  100 , an alternating current/direct current (AC/DC) converter  200 , an AC power supply system  300 , a DC power supply system  400 , and a controller  500 .  
      The power system  100  may provide an electrical input to the overall system. The power system  100  may comprise an on-board power supply, including but not limited to, an alternator, a starter/alternator, a battery, a generator, a fuel cell, and/or an exterior power supply to which the operator may have access.  
      The AC/DC converter  200  may be electrically connected to the power system  100  and may convert, if necessary, the electrical input from alternating current (AC) to direct current (DC). The AC/DC converter  200  may also convert the incoming current to a specified voltage rating. The AC/DC converter  200  may then output the DC electrical supply to the AC power supply system  300  and the DC power supply system  400 .  
      The AC power supply system  300  may be electrically connected to the AC/DC converter  200 . The AC power supply system  300  may receive DC from the AC/DC converter  200 . The AC power supply system may modify the incoming DC to the proper form, phase, and voltage rating for components that require an AC input.  
      The DC power supply system  400  may also be electrically connected to the AC/DC converter  200 . The DC power supply system  400  may receive a DC input from the AC/DC converter  200 , and it may modify the incoming DC to the proper or desired voltage rating appropriate for its components. The DC power supply system  400  may also provide the proper DC inputs to onboard DC components.  
      The controller  500  may be electrically connected to the AC/DC converter  200 , the AC power supply system  300 , and the DC power supply system  400 . The controller  500  may control the input of the power system  100  into the AC/DC converter  200 , the output of the AC/DC converter  200 , and the requirements of both the AC power supply system  300  and the DC power supply system  400 .  
      With continued reference to  FIG. 1 , the system in accordance with the first embodiment of the present invention may generally operate as follows. The power system  100  may input electrical power into the AC/DC converter  200 . The power system  100  may receive power from either an onboard system, such as, but not limited to a starter/alternator, or an external power source, such as, but not limited to a power hook-up at a truck stop. The AC/DC converter  200  may convert the power received from the power system  100  from alternating current to direct current. The voltage magnitude and rating of the output of the AC/DC converter  200  may be monitored and controlled by controller  500 . The AC/DC converter  200  may then output the DC to both the AC power supply system  300  and the DC power supply system  400 .  
      The AC power supply system  300  may receive the electrical input from the AC/DC converter  200 . The amount of power needed for the AC power supply system  300  may be determined by the controller  500 . Any excess power from the AC power supply system  300  may be returned to the AC/DC converter  200 . The AC power supply system  300  may modify the incoming DC to the proper phase, magnitude and voltage rating required by the AC power supply system  300  components.  
      The DC power supply system  400  may also receive an electrical input from the AC/DC converter  200 . The amount of power needed for the DC power supply system  400  may be determined by the controller  500 . The DC power supply system  400  may modify the magnitude and/or the voltage level of the incoming DC from the AC/DC converter  200  as required by the DC power supply system  400 . The DC power supply system  400  may then supply the necessary amounts of power to the DC components.  
      The controller  500  may control the input of the power system  100  into the AC/DC converter  200 , the output of the AC/DC converter  200 , and the requirements of both the AC power supply system  300  and the DC power supply system  400 . One method of monitoring the requirements of the AC power supply system  300  and the DC power supply system  400  is to monitor the required and/or desired loads of each respective system. The loads of each system may vary according to which and how many components are operated.  
       FIG. 2  illustrates a second embodiment of the present invention. The system  10  may comprise a power system  100 , an alternating current/direct current (AC/DC) converter  200 , an AC power supply system  300 , a DC power supply system  400 , and a controller  500 . In the second embodiment, the AC power supply system  300  may further comprise a DC/AC converter  325  and at least one AC load  350 . The DC power supply system may further comprise a DC/DC converter  425  and at least one DC load  450 .  
      The power system  100  may input electrical power, in either multi-phase AC current or single phase AC current, to the AD/DC converter  200 . The AC/DC converter  200  is controlled by the controller  500 . The controller  500  synchronizes the inputs of the AC/DC converter  200  so that the multi-phase AC input and single phase AC input are not provided as inputs into the AC/DC converter  200  simultaneously.  
      The output of the AC/DC converter  200  may then be provided as an input to the DC/AC converter  325  and the DC/DC converter  425 . The DC/AC converter  325  may convert the DC back into AC, while also modifying the current to be of the proper magnitude and voltage rating for the AC loads  350 . The DC/AC converter  325  may be monitored and controlled by the controller  500 . The DC/AC converter  325  may then output the AC to the AC loads  350 .  
      The DC/DC converter  425  may modify the electrical power provided as an input from the AC/DC converter  200  in order to supply an input of the proper magnitude and voltage rating to the DC loads  450 . The DC/DC converter  425  may be monitored and controlled by the controller  500 . The DC/DC converter  425  may then output the DC to the DC loads  450 .  
      With reference to  FIG. 3 , in which like reference characters refer to like elements, a third embodiment of the present invention will now be described. The power system  100  may further comprise an external power source  125  and/or an internal power source  150 , such as, but not limited to, a starter/alternator.  
      The AC power supply system  300  may include a DC/AC converter  325  and AC loads  350 . The AC loads  350  may be any electrical device powered by the onboard power system.  
      The DC power supply system  400  may include one or more DC/DC converters  425  and DC loads  450 . In addition, one DC load may comprise an eddy current retarder  430 .  
      When a truck is moving, the starter/alternator  150  may work as an alternator, producing an AC output. This AC output of the starter/alternator  150  is provided as an input to the AC/DC converter  200 , which converts the AC to DC. The output of the AC/DC converter  200  may match the requirements of the battery  410  and/or of other onboard DC loads. If the AC/DC converter&#39;s output  200  does not match the requirements of any DC load, the DC required for that specific load may be provided as an input to a DC/DC converter  425 , which may in turn provide power of the appropriate requirements. If a heavy-duty truck is equipped with any onboard AC loads, the output of the AC/DC converter  200  may be provided as an input to the DC/AC converter  325 . The DC/AC converter  325  may convert the power to the appropriate magnitude and/or frequency required by the AC loads. The magnitude and/or the frequency of the outputs of the AC/DC converter  200 , the DC/DC converter  425 , and/or the DC/AC converter  325  may be controlled by the controller  500 .  
      When the truck is not moving, for example at a truck stop, the engine may be shut down, and thus the alternator may not be running. If the truck stop is equipped with external power sources  125  (i.e., electrical outlets provided as power hook-ups), the AC/DC converter  200  may be directly attached to the power hook-up with a cable in order to provide electrical power to the onboard systems. The controller  500  may control the external power source  125  in order to prevent electrical power from the starter/alternator  150  and the external power source  125  from being provided to the AC/DC converter  200  simultaneously. Additionally, the controller  500  may generate a control signal for the AC/DC converter  200  when it is connected to the external power supply  125 . The control signal may be necessary if the AC/DC converter  200  is a multi-phase converter and the electrical power provided by the external power supply  125  is single phase. Now, instead of drawing electrical power from the starter/alternator  150 , power may be drawn from the power hook-up. The AC/DC converter  200  may be of a sufficiently high power rating to provide all of the electrical power needs of the onboard systems through the external power source  125 , and without the need for the truck to idle.  
      It will be apparent to those skilled in the art that various modifications and variations can be made in the construction, configuration, and/or operation of the present invention without departing from the scope or spirit of the invention.