Power management for multi-module energy storage systems in electric, hybrid electric, and fuel cell vehicles

• US 20080218104A1
• Filed: 10/23/2007
• Published: 09/11/2008
• Est. Priority Date: 03/09/2007
• Status: Active Grant

• Current Assignee: Turntide Technologies, Inc.
• Original Assignee: Illinois Institute of Technology
• Inventors: Emadi, Ali, Lukic, Srdjan
• Granted Patent: US 7,859,202 B2
• Time in Patent Office: Days
• US Class Current: 318/139
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

An electric energy storage system (EESS) for providing a power management solution for a multi-subsystem energy storage in electric, hybrid electric, and fuel cell vehicles. The EESS has a controller that determines when to draw power from each subsystem as needed by the vehicle.

Claims

1. An energy storage apparatus coupled with an electric motor/generator in a vehicle comprising:

a first subsystem including a first power source and a first converter, the first power source electrically connected with the first converter;

a second subsystem including a second power source and a second converter, the second power source electrically connected with the second converter;

an electric motor/generator;

a controller electrically connected to each of the first subsystem, the second subsystem, and the electric motor/generator, wherein the controller monitors an operating state of charge of each of the first and the second power sources to ensure that the two power sources, together or independently, have a minimum electrical power for the electric motor/generator;

wherein the controller directs electrical power from the electric motor/generator to the first power source or the second power source and the controller directs power from the first power source or the second power source to the electric motor/generator.

2. The apparatus according to claim 1, wherein the first converter and the second converter are part of a multi-input bi-directional converter DC/DC converter.

3. The apparatus according to claim 2, wherein the first power source comprises a battery.

4. The apparatus according to claim 3, wherein the second power source comprises an ultracapacitor.

5. The apparatus according to claim 4, wherein the controller further maintains the operating state of charge of the first power source at or above a predetermined minimum state of charge.

6. The apparatus according to claim 3, wherein the second power source comprises a second battery.

7. The apparatus according to claim 1, further comprising an internal combustion engine and a driveshaft, wherein the electric motor/generator and the internal combustion engine are coupled with the driveshaft to jointly or alternatively provide rotational motion to the driveshaft.

8. The apparatus according to claim 1, wherein the controller comprises a data processor and software code on a recordable medium and executable by the data processor.

9. A method for implementing an energy storage apparatus coupled with an electric motor/generator in a vehicle, the method comprising:

electrically connecting a controller between at least one converter and the electric motor/generator, the at least one converter including a first converter input electrically connected to a first power source and a second converter input electrically connected to a second power source;

monitoring with the controller a power demand of the electric motor/generator;

monitoring with the controller an operating state of charge of each of the first and second power sources;

powering the electric motor/generator with the controller using electrical power from at least one of the first and second power sources; and

recharging the at least one of the first and second power sources with the controller using electrical power generated by the electric motor/generator.

10. The method according to claim 9, wherein the converter comprises a multi-input bi-directional DC/DC converter.

11. The method according to claim 9, wherein the first power source comprises a battery.

12. The method according to claim 11, wherein the second power source comprises a second battery or an ultracapacitor.

13. The method according to claim 9, wherein the power demand is determined according to at least one of a vehicle parameter, a driving cycle of the vehicle, and the operating state of charge of each of the first and second power sources.

14. The method according to claim 9, wherein monitoring with the controller the operating state of charge of each of the first and second power sources comprises determining if the operating state of charge of the first power source or the second power source is below a predetermined maximum state of charge.

15. The method according to claim 14, wherein the first power source comprises a battery and the second power source comprises an ultracapacitor, and recharging the at least one the first and second power sources comprises:

determining with the controller a first amount of electrical power that is being generated by the electric motor/generator;

determining with the controller a second amount of electrical power to direct to the first power source to the maximum state of charge, wherein the second amount of electrical power is at least a portion of the first amount of electrical power;

determining with the controller a third amount of electrical power to direct to the second power source, wherein the third amount of electrical power is at least a portion of the first amount of electrical power;

16. The method according to claim 9, wherein monitoring with the controller the operating state of charge of each of the first and second power sources comprises determining if the operating state of charge of the first power source or the second power source is above a predetermined minimum state of charge.

17. The method according to claim 16, wherein the first power source comprises a battery and the second power source comprises an ultracapacitor and powering the electric motor/generator comprises:

determining with the controller an amount of electrical power that is required by the electric motor/generator;

determining with the controller a second amount of electrical power to direct from the first power source to the electric motor/generator, wherein the second amount of electrical power is at least a portion of the first amount of electrical power;

determining with the controller a third amount of electrical power to direct from the second power source, wherein the third amount of electrical power is at least a portion of the first amount of electrical power;

18. The method according to claim 9, wherein the vehicle comprises an internal combustion engine and a driveshaft, wherein the electric motor/generator and the internal combustion engine are coupled with the driveshaft to jointly or alternatively provide rotational motion to the driveshaft.

19. The method according to claim 9, wherein each of the first and second power sources comprises a lead-acid battery.

20. The method according to claim 19, further comprising:

establishing a threshold state of charge for each of the first and second power sources;

monitoring with the controller an operating state of charge for each of the first and second power sources;

determining the operating state of charge of one of the first and second power sources is at or below the threshold state of charge; and

powering the electric motor/generator with an other of the one of the first and second power sources when the one of the first and second power sources is at or below the threshold state of charge.

21. The method according to claim 20, further comprising directing electrical power with the controller from the electric motor/generator to the one of the first and second power sources when the operating state of charge is at or below the threshold state of charge.

22. The method according to claim 19, further comprising directing electrical power with the controller from the electric motor/generator to one of the first and second power sources on a predetermined schedule and powering the electric motor/generator with an other of the first and second power sources.