POWER CONTROL APPARATUS AND METHODS FOR ELECTRIC VEHICLES

• US 20140062401A1
• Filed: 08/24/2013
• Published: 03/06/2014
• Est. Priority Date: 08/24/2012
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Gadh, Rajit, Chu, Chi-Cheng, Chung, Ching-Yen, Qiu, Li
• Granted Patent: US 9,290,104 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 53/60 Monitoring or controlling charging stations
• CPC Class Codes: B60L 53/62 in response to charging parameters, e.g. current, voltage or electrical charge
• CPC Class Codes: B60L 53/66 Data transfer between charging stations and vehicles
• CPC Class Codes: B60L 53/67 Controlling two or more charging stations
• CPC Class Codes: B60L 53/68 Off-site monitoring or control, e.g. remote control
• 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
• CPC Class Codes: Y02T 90/167 Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/12 Remote or cooperative charging

Abstract

Electric vehicle (EV) charging apparatus and methods are described which allow the sharing of charge current between multiple vehicles connected to a single source of charging energy. In addition, this charge sharing can be performed in a grid-friendly manner by lowering current supplied to EVs when necessary in order to satisfy the needs of the grid, or building operator. The apparatus and methods can be integrated into charging stations or can be implemented with a middle-man approach in which a multiple EV charging box, which includes an EV emulator and multiple pilot signal generation circuits, is coupled to a single EV charge station.

Claims

1. An apparatus for charging electric vehicles, comprising:

a charging station configured for connecting multiple electric vehicles (EVs) to a single charging station for receiving and sharing current from a power grid;

a coordinator system coupled to each said charging station for generating multiple pilot control signals, one for each EV being charged, for communicating information with each of said multiple EVs and specifying maximum charge current available to each of said multiple EVs;

a gateway device configured for communicating with and controlling said coordinator system;

said gateway device sends commands to said coordinator system to set said maximum charge current for each EV in response to distributing an amount of charge current available at the charging station toward dividing it up across the number of EVs coupled to the charging station.

2. The apparatus recited in claim 1, wherein said charge current available is divided up equally to each charging EV, and upon determining that a given EV is using less than its maximum charge current specified by the pilot signal, then the current allotment to this vehicle is reduced by lowering maximum charge current level signaled in said pilot signal by the coordinator, and this additional current is made available to the other EVs charging from the charge station by increasing their allotment as signaled to the EV by raising its maximum charge current level signaled in said pilot signal by the coordinator.

3. The apparatus recited in claim 1, further comprising said gateway device determining a change in amount of charge current available at the charging station, and redetermining maximum charge current levels for each EV.

4. The apparatus recited in claim 3, wherein said change in the amount of charge current available is determined in response to determining present or predicted state of the power grid, or of allocations of current from that power grid.

5. The apparatus recited in claim 1, wherein said gateway device is configured with multiple communications channels, comprising at least a first communication channel for connection to a server over a communications network, and at least a second communications channel for connection to said coordinator system.

6. The apparatus recited in claim 1, wherein said first communication channel comprises a wireless mobile communications connection.

7. The apparatus recited in claim 1, wherein said second communication channel comprises a wireless short range communications connection.

8. The apparatus recited in claim 7, wherein said wireless short range communications connection comprises a ZigBee protocol.

9. The apparatus recited in claim 1, wherein each said coordinator system comprises a control unit having a computer processor, pilot signal generator and pilot signal monitor.

10. The apparatus recited in claim 1, wherein said pilot signals are generated according to SAE J1772 specification.

11. The apparatus recited in claim 1, wherein prior to starting to charge an EV of the EV user, the server obtains a user EV identification and charging station identification.

12. The apparatus recited in claim 11, wherein said user EV user identification is obtained in response to a user logging on to the server.

13. The apparatus recited in claim 12, wherein said charging station identification is obtained in response to the user scanning of a 1D or 2D barcode of said charging station on a mobile device of the user, which communicates both charging station identification and user information to the server.

14. The apparatus recited in claim 11, wherein user EV identification is obtained in response to retrieval of a user EV identification by a reader device at the charge station, after which the user EV identification along with associated charge station identification at which the card was read, are communicated to the server.

15. The apparatus recited in claim 14, wherein said reader device comprises a radio frequency identification (RFID) system reading an RFID tag or badge of the user or associated EV at the charge station.

16. The apparatus recited in claim 1, wherein said communication network connected to said server comprises an internet.

17. The apparatus recited in claim 1, further comprising meters coupled to said gateway for measuring voltage and current supplied to each of said multiple EVs being charged at the charging station.

18. The apparatus recited in claim 1, further comprising an EV emulator which controls operation of the single charging station by imitating an EV, making the single charging station believe an EV is present, while the coordinator is actually setting current flows to multiple EVs by communicating pilot signals these multiple EVs.

19. The apparatus recited in claim 18, wherein turning off said EV emulator causes the single charging station to turn off.

20. An apparatus for controlling charging of electric vehicles at a charging station, comprising:

a coordinator system configured for integration onto a single charging station that is configured for connecting multiple electric vehicles (EVs) to share current from the power grid connection of the single charging station;

said coordinator system is configured for generating multiple pilot control signals, one to each EV being charged, for communicating information with each of said multiple EVs and specifying maximum charge current available to each of said multiple EVs;

said coordinator system is also configured with an EV emulator which controls operation of the single charging station by imitating an EV, making the single charging station believe an EV is present so that it still generates EV charging power which now is being split between the multiple EVs;

a gateway device configured for communicating with and controlling said coordinator system;

said gateway device sends commands to said coordinator system to set said maximum charge current for each EV in response to distributing an amount charge current available from the single charging station toward dividing it up across the number of EVs coupled to the charging station.

21. A method of charging electric vehicles (EVs), comprising:

(a) inserting a middle-man layer between an internet and a single EV charging station connected to a power grid having a given state in relation to present power availability;

(b) communicating EV charging commands from a server to a gateway device in the middle-man layer; and

(c) communicating charging commands from the gateway device to a power coordinator in the middle-man layer, said power coordinator generating multiple pilot signals to multiple EVs coupled to the middle-man layer which shares the charging current available from the single EV charging station;

(d) modulating pulse widths in each of the multiple pilot signal configured for connection to multiple EVs for specifying maximum charge current available to each of these multiple EVs which are sharing charge current from said single EV charging station;

(e) emulating a single EV to the single EV charging station so that its control circuits still generate EV charging power which is now being split between the multiple EVs by the middle-man layer; and

(f) distributing an amount of charge current available at the charging station by dividing it up across the number of EVs coupled to the given charging station, and varying the current allocations to each EV based on user specified charge parameters, EV current use, as well as the state of the power grid or power allocations.

22. An electric vehicle charging apparatus, comprising:

a power input;

a plurality of power outputs;

a programmable processor; and

programming executable on the processor for multiplexing delivery of charging current from said power input to each said power output.

23. The apparatus of claim 22, wherein said programming multiplexes delivery of charging current from said power input to said power outputs to allow source capacity at said power input to be less than aggregate load connected to said power outputs.

24. The apparatus of claim 22, wherein said programming independently controls duty cycle and power level at each said power output.

25. The apparatus of claim 22, wherein said programming performs steps comprising:

(a) if a single load requires charging current, providing charging current to said single load;

(b) if a plurality of loads require charging current, dividing available charging current among said loads evenly; and

(c) if a load requires less charging current than is available to said load in step (b), reallocating excess charging current evenly among the remaining loads.

26. The apparatus of claim 22, wherein said programming performs steps comprising:

(a) retrieving and storing power capacity information from a charging station to which said power input is connected;

(b) monitoring charging current delivery to each said power output;

(c) determining if a new load connects to a power output;

(d) determining if a load connected to a power output requires charging current;

(e) determining if a load disconnects from a power output;

(f) if no load is connected to a power output requires charging current, waiting for a load to require charging current;

(g) if a single load requires charging current, providing charging current to said single load;

(h) if a plurality of loads require charging current, dividing available charging current among said loads evenly; and

(i) if a load requires less charging current than is available to said load in step (h), reallocating excess charging current evenly among the remaining loads.

27. The apparatus of claim 22, further comprising:

a communications interface connected to said processor;

wherein said processor is configured communicate with a server over said communications interface;

wherein said server provides instructions to said processor for providing charging current to a power output based on one or more charging parameters.

28. The apparatus of claim 27, wherein said charging parameters are selected from a group of parameters consisting of local grid power need, local grid power availability, local grid peak energy status, predicted peak energy periods, location of a charging station connected to said power input, and power availability to a charging station connected to said power input.

29. The apparatus of claim 27, further comprising:

a second communications interface connected to said processor;

wherein said second communications interface is configured for receiving a signal associated with a specific user'"'"'s load connected to a power output; and

wherein said charging parameters comprise user preferences selected from the group consisting of location where charging is permitted, time during which charging is permitted, cost of power for charging, and charge level at which a charge cycle is terminated.

30. A method for charging electric vehicles, comprising multiplexing delivery of charging current from a power input to a plurality of power outputs.

31. The method of claim 30, further comprising multiplexing delivery of charging current from said power input to said power outputs to allow source capacity at said power input to be less than aggregate load connected to said power outputs.

32. The method of claim 30, further comprising independently controlling duty cycle and power level at each said power output.

33. The method of claim 30, further comprising:

(a) if a single load requires charging current, providing charging current to said single load;

(b) if a plurality of loads require charging current, dividing available charging current among said loads evenly; and

(c) if a load requires less charging current than is available to said load in step (b), reallocating excess charging current evenly among the remaining loads.

34. The method of claim 30, further comprising:

(a) retrieving and storing power capacity information from a charging station to which said power input is connected;

(b) monitoring charging current delivery to each said power output;

(c) determining if a new load connects to a power output;

(d) determining if a load connected to a power output requires charging current;

(e) determining if a load disconnects from a power output;

(f) if no load is connected to a power output requires charging current, waiting for a load to require charging current;

(g) if a single load requires charging current, providing charging current to said single load;

(h) if a plurality of loads require charging current, dividing available charging current among said loads evenly; and

(i) if a load requires less charging current than is available to said load in step (h), reallocating excess charging current evenly among the remaining loads.

35. The method of claim 30, further comprising providing charging current to a power output based on one or more charging parameters selected from a group of parameters consisting of local grid power need, local grid power availability, local grid peak energy status, predicted peak energy periods, location of a charging station connected to said power input, and power availability to a charging station connected to said power input.

36. The method of claim 30, further comprising providing charging current to a power output based on one or more preferences of a user whose electric vehicle is connected to a power output, said preferences selected from the group consisting of location of the electric vehicle, time during which a user permits charging, cost of power for required for charging, and charge level at which a charge cycle is terminated.