Voltage drop compensation for an electric power storage device charging system

• US 8,120,363 B2
• Filed: 11/24/2008
• Issued: 02/21/2012
• Est. Priority Date: 11/24/2008
• Status: Active Grant

• Current Assignee: Cummins Power Generation IP, Inc.
• Original Assignee: Cummins Power Generation IP, Inc.
• Inventors: Fuchs, Benjamin S.
• Primary Examiner(s): DIAO, M BAYE
• Application Number:
  US12/313,709
• Publication Number:
  US 20100127668A1
• Time in Patent Office: 1,184 Days
• Field of Search: 324/426, 320/162
• US Class Current: 324/426
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/007186 obtained with the battery disconnected from the charge or discharge circuit
• CPC Class Codes: H02J 7/1415 with a generator driven by a prime mover other than the motor of a vehicle
• CPC Class Codes: H02J 7/1492 by means of controlling devices between the generator output and the battery

Abstract

A system includes an electrical energy storage device that may be in the form of one or more batteries, a charger to selectively charge the electrical energy storage device, and charger cabling sized to electrically interconnect the storage device and the charger together and span a distance separating them. The charger cabling is initially connected across the charger without the storage device to determine information specific to voltage drop caused by the cabling. The system is then reconfigured so that the cabling connects the storage device to the charger for charging. During this charging operation the previously gathered information is used to compensate for the voltage drop along the cabling as the storage device is charged with the charger.

Claims

1. A method, comprising:

selecting a first location for an electrical energy storage device and a second location for a charging device, the first location being spaced apart from the second location;

selecting one or more electrical conductors to extend between the first location and the second location;

configuring the one or more electrical conductors and the charging device in an evaluation configuration;

while in the evaluation configuration, flowing an evaluation electric current through the one or more electrical conductors from the charging device to determine information to account for voltage drop through the one or more electrical conductors;

reconfiguring the one or more electrical conductors to connect the electrical energy storage device and the charging device together in a charging configuration; and

while in the charging configuration, flowing a charging current from the charging device through the one or more conductors and the electrical energy storage device and compensating for the voltage drop through the one or more electrical conductors with the charging device based on the information.

2. The method of claim 1, wherein the flowing including controlling the evaluation electric current with the charging device and determining the voltage drop across the one or more electrical conductors.

3. The method of claim 1, wherein the electrical energy storage device includes a battery, the one or more electrical conductors includes two or more conductors, the two or more conductors are electrically connected in series between a first charger terminal and a second charger terminal of the charging device in the evaluation configuration without the electrical energy storage device being connected in series therewith, the battery includes a first battery terminal and a second battery terminal, and a first one of the two or more conductors is connected between the first charger terminal of the charging device and the first battery terminal and a second one of the two or more conductors is connected between the second charger terminal of the charging device and the second battery terminal in the charging configuration.

4. The method of claim 1, which includes storing the information in the charging device.

5. The method of claim 1, wherein the electrical energy storage device is not electrically connected to receive the evaluation electric current through the one or more electrical conductors while the charging device and the one or more conductors are in the evaluation configuration.

6. The method of claim 1, which includes:

providing an electric power generator connected to the charging device;

electrically powering the charging device with the electric power generator; and

driving the electric power generator with an internal combustion engine.

7. The method of claim 6, wherein:

the electrical energy storage device includes one or more batteries;

the one or more batteries, the one or more conductors, the charging device, the electric power generator, and the internal combustion engine are included in an auxiliary power generation system; and

the auxiliary power generation system further includes a transfer switch, the transfer switch including a first selectable power input connected to the auxiliary power generation system, a second selectable power input connected to an electric power grid, and an electric power output connected to an electric load.

8. A method, comprising:

providing an electric power generation system including an electrical energy storage device at a first location and a charger at a second location separated from the first location;

sizing cabling to extend between the electrical energy storage device at the first location and the charger at the second location;

flowing a first electric current through the cabling to determine information to account for voltage drop along the cabling;

electrically connecting the electrical energy storage device and the charger with the cabling;

charging the electrical energy storage device by providing a second electric current from the charger through the cabling and the electrical energy storage device; and

during the charging, compensating for the voltage drop through the cabling with the charger in accordance with the information.

9. The method of claim 8, which includes:

connecting the cabling across a first charging terminal of the charger and a second charging terminal of the charger to provide an evaluation configuration;

operating the charger in an evaluation mode to provide the first electric current through the cabling while in the evaluation configuration; and

configuring the evaluation configuration so that the first electric current does not flow through the electrical energy storage device.

10. The method of claim 8, wherein the electrical energy storage device includes one or more electrochemical batteries and cabling is one of:

an insulated single strand wire of no more than 10 AWG and multistrand wiring of no more than 10 AWG.

11. The method of claim 8, wherein the electric power generation system includes a transfer switch, and further comprising electrically connecting the charger to the transfer switch.

12. The method of claim 11, wherein the transfer switch includes an electric power output, a first input connected to the charger, and a second power input connected to an electric power grid.

13. The method of claim 8, which includes storing the information in the charger.

14. A system, comprising:

an electrical energy storage device;

a charger to selectively charge the electrical energy storage device;

charger cabling sized to electrically connect the electrical energy storage device and the charger together and span a distance separating the electrical energy storage device and the charger; and

the charger including operating logic to selectively operate the charger in;

(a) an evaluation mode to provide an evaluation electric current through the charger cabling and not the electrical energy storage device to determine information to account for voltage drop along the charger cabling and store the information in the charger and (b) a charge mode to provide a charging current from the charging device through the cabling and the electrical energy storage device and compensate for the voltage drop through the cabling in accordance with the information.

15. The system of claim 14, wherein the electrical energy storage device includes one or more electrochemical batteries.

16. The system of claim 15, further comprising:

a genset including an alternator and an internal combustion engine structure to drive the alternator; and

power circuitry electrically connected to the alternator and the charger.

17. The system of claim 16, further comprising a transfer switch including a first power input, a second power input, and a power output, the first power input being connected to the power circuitry to receive electricity therefrom.

18. The system of claim 17, wherein:

the charger includes means for selecting between the evaluation mode and the charge mode; and

the transfer switch includes means for selectively connecting the first power input or the second power input to the power output.

19. The system of claim 16, further comprising:

means for converting mechanical power to electric power for the charger; and

means for providing mechanical power to the converting means.

20. A system, comprising:

one or more batteries;

battery charger circuitry;

charger cabling sized to electrically connect the one or more batteries and the charger together; and

wherein the charger circuitry includes;

means for providing an evaluation electric current through the charger cabling and not the one or more batteries to determine information to account for voltage drop along the charger cabling, means for storing the information in the charger, means for charging the one or more batteries through the charger cabling, and means for compensating for the voltage drop through the charger cabling in accordance with the information.