SYSTEMS AND METHODS FOR CHARGING

• US 20130002197A1
• Filed: 06/29/2011
• Published: 01/03/2013
• Est. Priority Date: 06/29/2011
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Hernandez, Yaru Najem Mendez, El-Barbari, Said Farouk Said, Vyas, Parag
• Granted Patent: US 9,000,721 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 53/24 Using the vehicle's propulsion converter for charging
• CPC Class Codes: B60L 53/30 Constructional details of charging stations
• CPC Class Codes: B60L 53/34 Plug-like or socket-like devices specially adapted for contactless inductive charging of electric vehicles positioning means for charging devices using inductive energy transfer B60L53/38
• CPC Class Codes: B60L 53/67 Controlling two or more charging stations
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

An electric vehicle charging station is described. The charging station includes an input connector configured for coupling with an alternating current (AC) power source and an output connector configured for coupling with an electric vehicle. The charging station also includes a variable-output transformer comprising a primary side and a secondary side. The primary side is coupled to the input connector and the secondary side is coupled to the output connector and configured to be in selective electromagnetic communication with an energy storage device associated with the electric vehicle. The charging station also includes a controller coupled to the transformer and configured to determine a level of voltage to provide to the electric vehicle.

Claims

1. An apparatus comprising:

an input connector configured for coupling with an alternating current (AC) power source;

an output connector configured for coupling with an electric vehicle;

a variable-output transformer comprising a primary side and a secondary side, wherein said primary side is coupled to said input connector and said secondary side is coupled to said output connector and configured to be in selective electromagnetic communication with an energy storage device associated with the electric vehicle; and

a controller coupled to said transformer and configured to determine a level of voltage to provide to the electric vehicle.

2. An apparatus in accordance with claim 1, wherein said variable-output transformer further comprises a plurality of taps, and wherein said output connector is selectively coupled by at least one of a solid state and an electromechanical device to said plurality of taps to provide the determined level of voltage to the electric vehicle.

3. An apparatus in accordance with claim 1, wherein said controller is configured to receive a voltage level signal from the electric vehicle corresponding to a maximum voltage level.

4. An apparatus in accordance with claim 3, wherein said controller is configured to:

receive a switching frequency modulated to transmit said voltage level signal; and

demodulate the modulated switching frequency to determine the level of voltage to provide to the electric vehicle.

5. An apparatus in accordance with claim 1, wherein said controller is further configured to:

provide AC power to the electric vehicle at a first voltage level;

measure the power output of said transformer; and

increase the voltage level of the AC power provided to the electric vehicle until the power output of said transformer is limited by the electric vehicle.

6. An apparatus in accordance with claim 1, wherein said controller comprises a memory device configured to store a maximum current level, and wherein said controller is configured to:

provide AC power to the electric vehicle at a first voltage level;

measure a level of current drawn by the electric vehicle; and

increase the voltage level of the AC power provided to the electric vehicle until the level of current drawn by the electric vehicle equals the maximum current level.

7. An apparatus in accordance with claim 1, wherein said controller is configured to:

receive at least one of a voltage level signal and a current level signal corresponding to at least one of a voltage level and a current level of power provided by the AC power source to said input connector;

determine an available power based on the at least one of a voltage level signal and a current level signal;

compare the available power to a power level predefined as needed for non-vehicle charging loads also receiving power from the AC power source; and

limit the power output of said variable-output transformer to the difference between the available power level and the predefined power level.

8. An apparatus in accordance with claim 1, wherein said output connector is configured for coupling with an electric vehicle converter, wherein the electric vehicle converter is a bi-directional converter configured to convert a DC power from said energy storage device to AC power for powering an electric vehicle traction motor and to convert the AC power from said variable-output transformer to a DC power for charging said energy storage device.

9. A method comprising:

receiving AC power at a variable-output transformer; and

determining a level of voltage to be output from the variable-output transformer for use by an electric vehicle.

10. A method in accordance with claim 9, further comprising receiving a voltage level signal from the electric vehicle and determining the level of voltage to provide to the electric vehicle based at least partially on the voltage level signal.

11. A method in accordance with claim 10, further comprising demodulating a switching frequency of an electric vehicle power converter to determine the level of voltage to provide to the electric vehicle.

12. A method in accordance with claim 9, further comprising providing a switch actuation signal to a switching device positioned between the power converter and an electric motor within the electric vehicle, wherein the switch actuation signal uncouples the electric motor from the power converter and couples the power converter to the variable-output transformer.

13. A method in accordance with claim 9, further comprising regulating the power output of the variable-output transformer.

14. A method in accordance with claim 13, wherein regulating the power output of the variable-output transformer comprises:

receiving at least one of a voltage level signal and a current level signal from at least one sensor configured to measure an output power of an AC power source;

determining a level of power available from the AC power source;

comparing the available power level to a power level predefined as needed for non-vehicle charging loads; and

determining the power output of the variable-output transformer based on the difference between the available power level and the predefined power level.

15. An apparatus comprising:

an electric motor;

at least one direct current (DC) energy storage device configured to power said electric motor;

a power converter comprising a DC connector and an AC connector, said DC connector coupled to said at least one DC energy storage device;

a connection device selectively coupled to said AC connector for coupling with an AC power source; and

a switching device comprising a first position and a second position, wherein said first position couples said AC connector and said electric motor, and said second position couples said AC connector and said connection device.

16. An apparatus in accordance with claim 15, further comprising a system controller coupled to said power converter and configured to control operation of said power converter.

17. An apparatus in accordance with claim 16, wherein said system controller is further configured to transmit a voltage level signal to said connection device and the AC charging station, wherein the voltage level signal corresponds to a maximum voltage level at which to charge said DC energy storage device.

18. An apparatus in accordance with claim 17, wherein said system controller is configured to transmit the voltage level signal to said connection device and the AC charging station using at least one of a modulated switching frequency of said DC to AC converter and power line communications.

19. An apparatus in accordance with claim 15, wherein said switching device is configured to disconnect said motor from said power converter when AC power is applied to said connection device.

20. An apparatus in accordance with claim 15, wherein said electric motor, said at least one DC energy storage device, said power converter, said connection device, and said switching device are included within an electric vehicle.