OVERCURRENT AND GROUND FAULT PROTECTION IN A NETWORKED CHARGING STATION FOR ELECTRIC VEHICLES

• US 20110095723A1
• Filed: 01/06/2011
• Published: 04/28/2011
• Est. Priority Date: 06/02/2009
• Status: Active Grant

• Current Assignee: Chargepoint, Inc.
• Original Assignee: Coulomb Technologies Incorporated
• Inventors: Mandal, Praveen, Bhade, Harjinder, Tormey, Milton, Lowenthal, Richard, Baxter, David
• Granted Patent: US 8,072,184 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 2240/70 Interactions with external data bases, e.g. traffic centres
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 53/305 Communication interfaces
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• 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: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• 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
• 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
• CPC Class Codes: Y04S 30/14 : Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A networked charging station for electric vehicles protects against overcurrent and ground fault conditions. Upon detecting an overcurrent condition or a ground fault condition, the networked charging station for electric vehicles de-energizes a charging point connection to prevent electric current from flowing between an electric vehicle and the networked charging station and suspends the charging session. The networked charging station clears the overcurrent condition or the ground fault condition upon receipt of an authorized request which is transmitted remotely. The authorized request can be received from the vehicle operator that is associated with the charging session or from an administrator of the charging station through a radio-frequency identifier (RFID) tag enabled device or through a text message or an email message. The networked charging station clears the overcurrent condition or the ground fault condition without a manual reset of a circuit breaker or a GFCI device respectively.

Claims

1. A method for protecting against ground fault conditions in a networked charging station for electric vehicles, the method comprising:

receiving a request from an operator of an electric vehicle to establish a charging session for the electric vehicle;

establishing the charging session including energizing a charging point connection of the networked charging station to allow current to flow through a charging cord towards the electric vehicle;

responsive to detecting a ground fault condition, performing the following;

preventing current from flowing through the charging cord by de-energizing the charging point connection, and

suspending the charging session;

receiving a remote request to clear the detected ground fault condition; and

responsive to receiving the remote request to clear the ground fault condition, performing the following;

clearing the ground fault condition without a manual reset of a ground fault circuit interrupter device,

energizing the charging point connection, and

resuming the charging session.

2. The method of claim 1, wherein the request to establish the charging session is received from a mobile wireless communication device of the operator, and wherein the remote request to clear the detected ground fault condition is received from the operator of the electric vehicle via the mobile wireless communication device or a subscriber web portal, or received from an administrator of the networked charging station via a different mobile wireless communication device or a host portal.

3. The method of claim 1, further comprising:

responsive to detecting the ground fault condition, further performing the following;

causing a notification message to be transmitted to the operator that indicates that the charging session has been suspended.

4. The method of claim 1, further comprising:

responsive to detecting the ground fault condition, further performing the following;

causing a notification message to be transmitted to an administrator of the networked charging station that notifies that administrator of the ground fault condition.

5. The method of claim 1, further comprising protecting against overcurrent conditions, including performing the following:

responsive to detecting an overcurrent condition, performing the following;

preventing current from flowing through the charging cord by de-energizing the charging point connection, and

suspending the charging session;

receiving a remote request to clear the detected overcurrent condition; and

responsive to receiving the remote request to clear the detected overcurrent condition, performing the following;

clearing the overcurrent condition without a manual reset of a circuit breaker coupled with the networked charging station for electric vehicles,

energizing the charging point connection, and

resuming the charging session.

6. The method of claim 5, further comprising:

responsive to detecting the overcurrent condition, further performing the following;

causing a notification message to be transmitted to the operator that indicates that the charging session has been suspended.

7. The method of claim 5, further comprising:

responsive to detecting the overcurrent condition, further performing the following;

causing a notification message to be transmitted to an administrator of the networked charging station that notifies that administrator of the overcurrent condition.

8. The method of claim 5, wherein the request to establish the charging session is received from a mobile wireless communication device of the operator, and wherein the remote request to clear the detected overcurrent condition is received from the operator of the electric vehicle via the mobile wireless communication device or a subscriber web portal, or received from an administrator of the networked charging station via a different mobile wireless communication device or a host portal.

9. The method of claim 5, wherein the charging point connection is one of a power receptacle and an attached charging cord.

10. A networked charging station for electric vehicles, comprising:

a charging point connection to couple electric vehicles to a power line coupled with a power grid;

an electricity control device coupled with the charging point connection to control the flow of electricity to the charging point connection;

a current measuring device coupled with the charging point connection to measure electric current flowing on the power line through the charging point connection;

a GFCI (Ground Fault Circuit Interrupter) device coupled with the electricity control device, the GFCI device to detect ground fault conditions and cause the electricity control device to de-energize the charging point connection when it detects a ground fault condition; and

the charging station controller coupled with the electricity control device, the current measuring device, and the GFCI device, wherein the charging station controller is to perform the following;

suspend a charging session responsive to the GFIC device detecting a ground fault condition, and

responsive to receipt of an authorized request to clear a ground fault condition, cause the electricity control device to energize the charging point connection without a manual reset of the GFCI device and resume the charging session.

11. The networked charging station for electric vehicles of claim 10, further comprising:

an RFID (Radio-frequency identification) reader to read RFID tags from mobile communication devices and pass that information to the charging station controller; and

wherein requests to clear the ground fault conditions are to be received through the RFID reader and provided to the charging station controller.

12. The networked charging station for electric vehicles of claim 11, further comprising:

a set of one or more transceivers to communicate with an electric vehicle charging station network server including;

transmission of information received from the RFID reader to the electric vehicle charging station network server for authorization, and

transmission of charging session status update messages that indicate a change in charging session status from active to suspended, and from suspended to active.

13. The networked charging station for electric vehicles of claim 10, wherein responsive to the GFCI device detecting a ground fault condition, the charging station controller is further to cause a notification message to be transmitted to an administrator of the networked charging station for electric vehicles that notifies that administrator of the ground fault condition.

14. The networked charging station for electric vehicles of claim 10, wherein the charging point connection is one of a power receptacle and an attached charging cord.

15. The networked charging station for electric vehicles of claim 10, wherein the charging station controller is to receive current data from the current measuring device and is further to perform the following:

detect overcurrent conditions based on the current data received from the current measuring device, and responsive to detecting an overcurrent condition, suspend a charging session and cause the electricity control device to de-energize the charging point connection,

wherein the charging station controller is further to, responsive to receipt of an authorized request to clear an over current condition, cause the electricity control device to energize the charging point connection without a manual reset of a circuit breaker coupled with the networked charging station for electric vehicles, and resume the charging session.

16. The networked charging station for electric vehicles of claim 15, wherein the charging station controller is further to cause notification messages to be transmitted to operators of electric vehicles when their charging sessions have been suspended.

17. The networked charging station for electric vehicles of claim 15, wherein the charging station controller is further to, in response to detecting an overcurrent condition, cause a notification message to be transmitted to an administrator of the networked charging station for electric vehicles that notifies that administrator of the overcurrent condition.

18. A non-transitory computer-readable storage medium that provides instructions that, if executed by a processor, will cause said processor to perform operations comprising:

receiving a request from an operator of an electric vehicle to establish a charging session for the electric vehicle;

establishing the charging session including energizing a charging point connection of a networked charging station to allow current to flow through a charging cord towards the electric vehicle;

responsive to detecting a ground fault condition, performing the following;

preventing current from flowing through the charging cord by de-energizing the charging point connection, and

suspending the charging session;

receiving a remote request to clear the detected ground fault condition; and

responsive to receiving the remote request to clear the ground fault condition, performing the following;

clearing the ground fault condition without a manual reset of a ground fault circuit interrupter device,

energizing the charging point connection, and

resuming the charging session.

19. The non-transitory computer-readable storage medium of claim 18, wherein the request to establish the charging session is received from a mobile wireless communication device of the operator, and wherein the remote request to clear the detected ground fault condition is received from the operator of the electric vehicle via the mobile wireless communication device or a subscriber web portal, or received from an administrator of the networked charging station via a different mobile wireless communication device or a host portal.

20. The non-transitory computer-readable storage medium of claim 18, further comprising:

responsive to detecting the ground fault condition, further performing the following;

causing a notification message to be transmitted to the operator that indicates that the charging session has been suspended.

21. The non-transitory computer-readable storage medium of claim 18, further comprising:

responsive to detecting the ground fault condition, further performing the following;

causing a notification message to be transmitted to an administrator of the networked charging station that notifies that administrator of the ground fault condition.

22. The non-transitory computer-readable storage medium of claim 18, further comprising protecting against overcurrent conditions, including performing the following:

responsive to detecting an overcurrent condition, performing the following;

preventing current from flowing through the charging cord by de-energizing the charging point connection, and

suspending the charging session;

receiving a remote request to clear the detected overcurrent condition; and

responsive to receiving the remote request to clear the detected overcurrent condition, performing the following;

clearing the overcurrent condition without a manual reset of a circuit breaker coupled with the networked charging station for electric vehicles,

energizing the charging point connection, and

resuming the charging session.

23. The non-transitory computer-readable storage medium of claim 22, further comprising:

responsive to detecting the overcurrent condition, further performing the following;

causing a notification message to be transmitted to the operator that indicates that the charging session has been suspended.

24. The non-transitory computer-readable storage medium of claim 22, further comprising:

responsive to detecting the overcurrent condition, further performing the following;

causing a notification message to be transmitted to an administrator of the networked charging station that notifies that administrator of the overcurrent condition.

25. The non-transitory computer-readable storage medium of claim 22, wherein the request to establish the charging session is received from a mobile wireless communication device of the operator, and wherein the remote request to clear the detected overcurrent condition is received from the operator of the electric vehicle via the mobile wireless communication device or a subscriber web portal, or received from an administrator of the networked charging station via a different mobile wireless communication device or a host portal.

26. The non-transitory computer-readable storage medium of claim 22, wherein the charging point connection is one of a power receptacle and an attached charging cord.