Apparatus and method for hybrid power module systems

• US 7,521,138 B2
• Filed: 06/23/2004
• Issued: 04/21/2009
• Est. Priority Date: 05/07/2004
• Status: Expired due to Fees

• Current Assignee: Ballard Power Systems Corporation (Superior Plus Corporation)
• Original Assignee: Ballard Power Systems Corporation (Superior Plus Corporation)
• Inventors: Pearson, Martin T.
• Primary Examiner(s): Crepeau; Jonathan
• Assistant Examiner(s): CHUO, TONY SHENG HSIANG
• Application Number:
  US10/875,622
• Publication Number:
  US 20050249988A1
• Time in Patent Office: 1,763 Days
• Field of Search: None
• US Class Current: 429/9
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 8/04373 of auxiliary devices, e.g. reformers, compressors, burners
• CPC Class Codes: H01M 8/04395 of cathode reactants at the inlet or inside the fuel cell
• CPC Class Codes: H01M 8/04447 of anode reactants at the inlet or inside the fuel cell
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04567 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04597 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/0491 of fuel cell stacks
• CPC Class Codes: H01M 8/04917 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A hybrid power module suitable for use in an array of hybrid power modules comprises a fuel cell stack, an energy storage device, charger circuit operable to charge the energy storage device from the fuel cell stack and/or an external power source at approximately a defined voltage; a stack disconnect switch operable to provide and remove an electrical path between the fuel cell stack and a terminal of the power module, and a unidirectional current flow device electrically coupled to provide a unidirectional current path from the charger circuit to the terminal of the power module when forward biased.

Claims

1. A hybrid power module configured to modularly couple to and decouple from a power system housing having a system power bus for providing electrical power to at least two terminals electrically couplable to an external load, comprising:

a module power bus comprising at least a first releasably couplable electrical bus terminal and a second releasably couplable electrical bus terminal, the first releasably couplable electrical bus terminal and the second releasably couplable electrical bus terminal being configured to releasably and electrically couple to and electrically decouple from a system power bus of a power system;

a plurality of fuel cells electrically coupled to one another as a fuel cell stack, the fuel cell stack comprising a first pole electrically couplable to and electrically decouplable from the first releasably couplable electrical bus terminal and a second pole electrically coupled to the second releasably couplable electrical bus terminal, the fuel cell stack configured to selectively produce electrical power, and electrically couplable to provide the electrical power on the module power bus;

an energy storage device comprising a first pole electrically couplable to and electrically decouplable from the first releasably couplable electrical bus terminal and a second pole electrically couplable to and electrically decouplable from the second releasably couplable electrical bus terminal, wherein the first releasably couplable electrical bus terminal, the first pole of the fuel cell stack and the first pole of the energy storage device have a common first electrical polarity, and the second releasably couplable electrical bus terminal, the second pole of the fuel cell stack and the second pole of the energy storage device have a common second electrical polarity that is opposite the common first electrical polarity, and the energy storage device configured to store electrical power and configured to release electrical power to the first releasably couplable electrical bus terminal and the second releasably couplable electrical bus terminal;

a first linear regulator electrically coupled between the first pole of the fuel cell stack and the first releasably couplable electrical bus terminal of the module power bus, and configured to regulate a flow of current from the first pole of the fuel cell stack to the first releasably couplable electrical bus terminal;

at least two input terminals releasably and electrically couplable to an external power connector that is distinct from the hybrid power module to receive power from an external power source that is distinct from the hybrid power module via the external power connector; and

a charger circuit comprising a first pole and a second pole, the charger circuit electrically coupled across the energy storage device such that the respective first poles of the charger circuit and the energy storage device are electrically coupled and have the first electrical polarity and such that the respective second poles of the charger circuit and the energy storage device are electrically coupled and have the second electrical polarity, and the charger circuit configured to supply electrical power to the energy storage device at approximately a defined voltage and charging regime, the charger circuit comprising a second linear regulator electrically coupled between the first pole of the energy storage device and a node electrically located between the first pole of the fuel cell stack and at least one of the at least two input terminals, the second linear regulator configured to regulate a flow of a first current from the first pole of the fuel cell stack to the energy storage device when the second pole of the fuel cell stack is electrically coupled to the second releasably couplable electrical bus terminal and configured to regulate a flow of a second current from at least one of the at least two input terminals releasably and electrically couplable to the external power connector when the second pole of the fuel cell stack is electrically decoupled from the second releasably couplable electrical bus terminal.

2. The hybrid power module of claim 1, further comprising:

a stack disconnect switch configured to selectively provide and remove an electrical path between the second releasably couplable electrical bus terminal of the module power bus and the second pole of the fuel cell stack in a first state and a second state, respectively.

3. The hybrid power module of claim 1, further comprising:

a first controller communicatively coupled to control the first linear regulator based on a number of system operational parameters.

4. The hybrid power module of claim 3, further comprising:

a second controller communicatively coupled to control the second linear regulator based on a number of energy storage device operational parameters.

5. The hybrid power module of claim 1 wherein the first linear regulator comprises a plurality of regulating transistors electrically coupled in parallel with one another between the first pole of the fuel cell stack and the first releasably couplable electrical bus terminal of the module power bus.

6. The hybrid power module of claim 1, further comprising:

a stack protection diode electrically coupled between the first pole of the fuel cell stack and the first releasably couplable electrical bus terminal of the module power bus such that the stack protection diode substantially protects the fuel cell stack from currents received from the first releasably couplable electrical bus terminal and from the energy storage device.

7. The hybrid power module of claim 1, further comprising:

a redundancy diode electrically coupled between the first pole of the energy storage device and the first releasably couplable electrical bus terminal of the module power bus to allow current to flow from the first pole of the energy storage device to the first releasably couplable electrical bus terminal when the redundancy diode is forward biased, and to prevent current from flowing from the first releasably couplable electrical bus terminal to the first pole of the energy storage device when the redundancy diode is reversed biased.

8. The hybrid power module of claim 1, further comprising:

a first diode electrically coupled between the node and the first pole of the fuel cell stack to allow a current flow from the first pole of the fuel cell stack to the first linear regulator when the first diode is forward biased; and

a second diode electrically coupled between the node and one of the at least two input terminals to allow a current flow from the one of the at least two input terminals to the first linear regulator when the second diode is forward biased.

9. The hybrid power module of claim 1 wherein the first and second releasably couplable electrical bus terminals are externally accessible from the hybrid power module to releasably and electrically couple to the system power bus.

10. The hybrid power module of claim 1, further comprising:

a power converter electrically coupled to the node and electrically coupled to receive power from the at least two input terminals and to provide power converted therefrom to the energy storage device via the charger circuit.

11. The hybrid power module of claim 10 wherein the power converter comprises a rectifier.

12. The hybrid power module of claim 10 wherein the power converter comprises a universal power supply configured to convert both AC and DC power within a first voltage range to DC power of a defined nominal voltage.

13. The hybrid power module of claim 1 wherein the at least two input terminals comprise a first, a second, and a third input terminals, the first, the second and the third input terminals releasably and electrically couplable to a three phase alternating current power source via the external power connector.

14. The hybrid power module of claim 1 wherein the energy storage device comprises a plurality of battery cells electrically coupled to one another as a battery.

15. The hybrid power module of claim 1 wherein the first and the second releasably couplable electrical bus terminals are further electrically coupled in an array of hybrid power modules via the system power bus.

16. The hybrid power module of claim 1 wherein the first and the second bus releasably couplable electrical terminals are further releasably and electrically coupled to at least one external energy storage device that is external to, and distinct from, the hybrid power module.

17. The hybrid power module of claim 1, further comprising:

at least one subsystem that comprises a portion of a balance of plant of the hybrid power module, the subsystem comprising at least one device electrically coupled across the module power bus to receive power from the module power bus.

18. The hybrid power module of claim 17, further comprising:

a hybrid power module housing carrying the at least one subsystem and configured complimentary to a hybrid power module housing receiving position of a housing of the power system such that the hybrid power module housing is removably receivable therein.

19. The hybrid power module of claim 18 wherein the hybrid power module housing further carrying the energy storage device and the charger circuit, wherein the energy storage device and the charger circuit are electrically isolated from the system power bus when the first and the second releasably couplable electrical bus terminals are electrically isolated from the system power bus.

20. The hybrid power module of claim 18 wherein the at least one subsystem includes:

a stack disconnect switch configured to selectively provide and remove an electrical path between the second releasably couplable electrical bus terminal of the module power bus and the second pole of the fuel cell stack in a first state and a second state, respectively;

a controller communicatively coupled to control the first linear regulator and the stack disconnect switch based on a number of system operational parameters.

21. The hybrid power module of claim 20 wherein the stack disconnect electrically decouples each and every fuel cell in the hybrid power module from second releasably couplable electrical bus terminal of the module power bus when the stack disconnect electrically is in the second state.

22. A hybrid power module in an array of multiple hybrid power modules, each respective hybrid power module received by a respective hybrid power module position of multiple respective hybrid power module positions of a housing of a hybrid power system having a system power bus coupling the array of power modules to a first and a second terminal of the system power bus, the hybrid power module comprising:

a module power bus comprising a first releasably couplable electrical bus terminal and a second releasably couplable electrical bus terminal, the first releasably couplable electrical bus terminal and the second releasably couplable electrical bus terminal being configured to releasably and electrically couple to the system power bus of the power system;

a plurality of fuel cells electrically coupled to one another as a fuel cell stack, the fuel cell stack comprising a first pole electrically couplable to the first releasably couplable electrical bus terminal and a second pole electrically couplable to the second releasably couplable electrical bus terminal, the fuel cell stack selectively configured to produce electrical power, and electrically couplable to provide the electrical power on the module power bus;

an energy storage device comprising a first pole electrically coupled to the first releasably couplable electrical bus terminal and a second pole electrically couplable to the second releasably couplable electrical bus terminal, and the energy storage device configured to store and configured to release electrical power to the first releasably couplable electrical bus terminal and the second releasably couplable electrical bus terminal, wherein the first pole of the fuel cell stack and the first pole of the energy storage device have a common first electrical polarity, and wherein the second pole of the fuel cell stack and the second pole of the energy storage device have a common second electrical polarity that is opposite the first electrical polarity;

a linear regulator electrically coupled between the first pole of the fuel cell stack and the first releasably couplable electrical bus terminal of the module power bus, and configured to regulate a flow of current from the first pole of the fuel cell stack to the first releasably couplable electrical bus terminal;

at least two input terminals releasably and electrically couplable to an external power connector that is distinct for the hybrid power module to receive power from an external power source that is distinct from the hybrid power module via the external power connector;

a charger circuit electrically coupled across the energy storage device and configured to supply electrical power to the energy storage device at approximately a defined voltage and charging regime, the charger circuit electrically coupled between the first pole of the energy storage device and a node electrically located between the first pole of the fuel cell stack and at least one of the at least two input terminals, the charger circuit configured to receive from the node input currents and configured to regulate a flow of an output current to the energy storage device, the input currents including a first current from the first pole of the fuel cell stack when the second pole of the fuel cell stack is electrically coupled to the second releasably couplable electrical bus terminal and a second current from at least one of the at least two input terminals releasably and electrically couplable to the external power connector when the second pole of the fuel cell stack is electrically decoupled from the second releasably couplable electrical bus terminal; and

a module housing configured complimentary to a respective one of the multiple hybrid power module positions of the housing of the hybrid power system such that the module housing is releasably received therein, the module housing carrying at least the charger circuit and energy storage device and configured to provide access external from the module housing to the first and the second releasably couplable electrical terminals.

23. The hybrid power module of claim 22, further comprising:

at least one reactant supply coupler structure configured to removably couple to and decouple from a reactant supply system external to the hybrid power module, wherein the module housing is configured to provide external access to the at least one reactant supply coupler structure.

24. The hybrid power module of claim 23, further comprising:

at least one subsystem that comprises a portion of a balance of plant of the hybrid power module, the subsystem carried by the module housing and comprising at least one device electrically coupled across the module power bus to receive power from the module power bus.

25. The hybrid power module of claim 23, further comprising:

a controller electrically coupled to the module power bus and communicatively coupled to the at least one subsystem and carried by the module housing and configured to control the linear regulator, wherein the at least one subsystem and the controller are electrically isolated from the system power bus when the first and the second releasably couplable electrical bus terminals are electrically isolated from the system power bus.

26. The hybrid power module of claim 23 wherein the controller is configured to place the hybrid power module in a standby state, further comprising:

a communications port that is active when the hybrid power module is in the standby state, and the communications port is configured to provide a system controller of the hybrid power module system access to the hybrid power module when the hybrid power module is in the standby state.

27. The hybrid power module of claim 22, further comprising:

a stack disconnect switch configured to selectively provide and remove an electrical path between the second releasably couplable electrical bus terminal of the module power bus and the second pole of the fuel cell stack in a first state and a second state, respectively, wherein when the electrical path between the second releasably couplable electrical bus terminal of the module power bus and the second pole of the fuel cell stack is removed, each and every fuel cell of the hybrid power module is electrically decoupled from the second releasably couplable electrical bus terminal.