Apparatus and method for charging an electric vehicle

• US 8,994,327 B2
• Filed: 08/24/2011
• Issued: 03/31/2015
• Est. Priority Date: 08/24/2011
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kusch, Ruediger Soeren, King, Robert Dean
• Primary Examiner(s): Berhanu, Samuel
• Application Number:
  US13/216,590
• Publication Number:
  US 20130049684A1
• Time in Patent Office: 1,315 Days
• Field of Search: 320/109, 180/65.21, 307/150
• US Class Current: 320/109
• CPC Class Codes: B60L 2200/36 Vehicles designed to transport cargo, e.g. trucks
• CPC Class Codes: B60L 2200/42 Fork lift trucks
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2240/527 Voltage
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: Y02P 90/60 Electric or hybrid propulsion means for production processes
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

An energy storage and management system (ESMS) includes energy storage devices coupled to a power device, a power electronic conversion system that includes a plurality of DC electrical converters, each DC electrical converter configured to step up and to step down a DC voltage, wherein energy ports of the ESMS are coupleable to each of the energy storage devices, and each of the energy ports is coupleable to an electrical charging system. The ESMS includes a controller configured to determine a first condition of a first energy storage device and a second condition of a second energy storage device, wherein the first and second energy storage devices are each connected to respective energy ports of the power conversion system, determine a power split factor based on the first condition and on the second condition, and regulate power to the first and second energy storage devices based on the power split factor.

Claims

1. An energy storage and management system (ESMS) comprising:

one or more energy storage devices positioned on-board a vehicle and coupled to a power device and configured to store electrical energy;

a power electronic conversion system having a plurality of energy ports, the power electronic conversion system comprising a plurality of DC electrical converters, each DC electrical converter configured to step up and to step down a DC voltage, wherein;

each of the plurality of energy ports is coupleable to each of the one or more energy storage devices; and

each of the plurality of energy ports is coupleable to an electrical charging system located off-board the vehicle; and

a controller configured to;

detect connection of an electrical charging system located off-board the vehicle to one or more of the plurality of energy ports, with at least one of a voltage and frequency of the electrical charging system being determined;

determine a first condition of a first energy storage device and a second condition of a second energy storage device, wherein the first and second energy storage devices are each connected to respective energy ports of the power conversion system;

determine a power split factor based on the first condition and on the second condition; and

selectively operate the plurality of DC electrical converters in the ESMS based on the power split factor and based on the at least one of the voltage and frequency of the electrical charging system, so as to regulate power to the first and second energy storage devices.

2. The system of claim 1 wherein the condition of the first energy storage device and the condition of the second energy storage device comprise one of a state-of-charge (SOC) and an amount of cell imbalance.

3. The system of claim 1 wherein the controller is configured to continuously monitor the first condition and the second condition, and revise the power split factor as a function of a changed first condition of the first energy storage device and of a changed second condition of the second energy storage device.

4. The system of claim 1 wherein, in determining the power split factor, the controller is configured to regulate power such that 100% of the power is directed to only one of the first and second energy storage devices.

5. The system of claim 1 wherein the controller is configured to determine the power split factor based on at least one of a capacity of the first and second energy storage devices and on a charging current limit of one of the first and second energy storage devices.

6. The system of claim 1 wherein the controller is configured to:

determine a voltage of each energy port having either an energy storage device or a DC electrical charging system coupled thereto;

determine the power split factor based on the determined voltage of each respective energy port; and

electrically connect a first energy port to a second energy port of at least two of the plurality of energy ports such that at least one of the DC electrical converters either steps up or steps down an input DC voltage based on the regulation of power to the first and second energy storage devices.

7. The system of claim 1 wherein the power device comprises one of a vehicle drivetrain, an uninterrupted power supply, a mining vehicle drivetrain, a mining apparatus, a marine system, and an aviation system.

8. A method of managing an energy storage and management system (ESMS) comprising:

determining a first charge status of a first energy storage device;

determining a second charge status of a second energy storage device;

detecting connection of a charging power source located off-board of a system on which the first and second storage devices are included;

determining at least one of a voltage and frequency of a charging power received from the charging power source;

determining a power split factor based on the first charge status and the second charge status; and

regulating charging power to the first and second energy storage devices consistent with the power split factor and based on the at least one of the voltage and frequency of the charging power;

wherein regulating the charging power comprises selectively operating a plurality of switching devices and a plurality of buck-boost converters included in the ESMS to regulate the charging power to the first and second energy storage devices.

9. The method of claim 8 wherein determining the first charge status and the second charge status comprises determining one of a state-of-charge (SOC) and an amount of cell imbalance.

10. The method of claim 8 comprising:

monitoring the first charge status and the second charge status for change;

re-determining the power split factor based on the change; and

regulating the charging power to the first and second energy storage devices consistent with the re-determined power split factor.

11. The method of claim 8 wherein determining the power split factor comprises regulating the charging power such that 100% of the power is directed to only one of the first and second energy storage devices.

12. The method of claim 8 wherein determining the power split factor comprises determining the power split factor based on at least one of a capacity of the first and second energy storage devices and on a charging current limit of one of the first and second energy storage devices.

13. The method of claim 8 comprising:

electrically connecting the first energy storage device to a first energy port of the ESMS; and

electrically connecting the second energy storage device to a second energy port of the ESMS;

wherein determining the first charge status comprises determining a voltage of the first energy port; and

wherein determining the second charge status comprises determining a voltage of the second energy port.

14. The method of claim 13 comprising electrically connecting the first energy port to the second energy port via one or more DC electrical converters, such that at least one of the DC electrical converters either steps up or steps down an input DC voltage to a third energy port of the ESMS based on the regulation of power to the first and second energy storage devices.

15. The method of claim 8 wherein the first energy storage device and the second energy storage device are electrically connected to a power device.

16. The method of claim 15 wherein the power device comprises one of a vehicle drivetrain, an uninterrupted power supply, and an aviation system.

17. A non-transitory computer readable storage medium positioned on an energy storage and management system (ESMS) comprising a plurality of energy ports, a plurality of switching devices, and a plurality of buck-boost converters, the non-transitory computer readable storage medium having stored thereon a computer program comprising instructions which when executed by a computer cause the computer to:

determine an electrical status of a first energy storage device and of a second energy storage device, wherein the first and second energy storage devices are each connected to respective energy ports of the ESMS;

determine an electrical status of an electrical charging system connected to another energy port of the ESMS, the electrical charging system comprising one of an AC power grid, an AC charging station, or a high voltage DC charger;

determine a power split factor based on the electrical status of the first and second energy storage devices; and

regulate power to the first and second energy storage devices based on the power split factor and based on the electrical status of the electrical charging system;

wherein regulating the power to the first and second energy storage devices comprises selectively operating the plurality of switching devices and the plurality of buck-boost converters included in the ESMS to regulate the power to the first and second energy storage devices.

18. The computer readable storage medium of claim 17 wherein the computer is caused to determine the status of the first energy storage device and of the second energy storage device based on one of a state-of-charge (SOC) and an amount of cell imbalance of each of the first and second energy storage devices.

19. The computer readable storage medium of claim 17 wherein the computer continuously monitors the electrical status of the first and second energy storage devices for change, and the computer is further caused to revise the power split factor based on the change.

20. The computer readable storage medium of claim 17 wherein, in determining the power split factor, the computer is caused to cause 100% of the power to flow to only one of the first and second energy storage devices for a first time period.

21. The computer readable storage medium of claim 20 wherein the first time period is determined based on the charge status of the only one energy storage device to which power is regulated to flow.

22. The computer readable storage medium of claim 20 wherein, upon passage of the first time period, the computer is programmed to re-determine the power split factor and regulate power to flow to both the first and second energy storage devices.

23. The computer readable storage medium of claim 17 wherein the computer is configured to determine the power split factor based on at least one of a capacity of the first and second energy storage devices and on a charging current limit of one of the first and second energy storage devices.

24. The computer readable storage medium of claim 17 wherein the computer is caused to:

determine a voltage of each energy storage device;

determine the power split factor based on the determined voltage of each respective energy port; and

electrically connect a first energy port to a second energy port of at least two of the plurality of energy ports such that at least one of the plurality of buck-boost converters either steps up or steps down an input DC voltage based on the regulation of power to the first and second energy storage devices.