Plug-in electric vehicle charger validation and test device

• US 9,075,098 B2
• Filed: 01/16/2013
• Issued: 07/07/2015
• Est. Priority Date: 01/16/2013
• Status: Expired due to Fees

• Current Assignee: Gridtest Systems LLC
• Original Assignee: Gridtest Systems LLC
• Inventors: Schurman, Thomas Michael, Oster, Melvin G., Tobol, Nathan H.
• Primary Examiner(s): Baldridge, Benjamin M
• Application Number:
  US13/743,183
• Publication Number:
  US 20140197843A1
• Time in Patent Office: 902 Days
• Field of Search: 324/509
• US Class Current: 1/1
• CPC Class Codes: B60L 3/00 Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption methods or circuit arrangements for monitoring or controlling batteries or fuel cells B60L58/00
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 53/62 in response to charging parameters, e.g. current, voltage or electrical charge
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• 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

A process and apparatus for performing a ground fault test of a device is disclosed. A current level may be selected from a plurality of predetermined current levels. A ground fault current may be generated between a first power line and a ground at the selected current level until a ground fault interrupter within the device trips, or until expiration of an on-time period associated with the selected current level. The ground fault current may then be set to zero for an off-time period associated with the selected current level. The process may be repeated for each of the plurality of current levels. When the ground fault interrupter within the device trips, the current level and a time interval from an onset of the ground fault current at the selected level and a time when the ground fault interrupter tripped may be recorded.

Claims

1. A process for performing a ground fault test of a device that delivers power to a load via one or more power lines, the process comprising:

programming a controller to execute, or cause to be executed, the process steps;

selecting a current level of a controllable current generator from a plurality of different current levels;

generating a ground fault current with the controllable current generator between a first power line of the one or more power lines and ground at the selected current level until a ground fault interrupter within the device trips in response to the ground fault current, or until expiration of an on-time interval associated with the selected current level, whichever occurs first;

after generating the ground fault current at the selected current level, setting the ground fault current to zero for an off-time interval associated with the selected current level, and repeating the selecting, generating, and setting for each of the plurality of current levels, wherein;

when the ground fault interrupter within the device trips, the process further comprises;

reporting the selected current level at which the ground fault interrupter tripped, and a time interval from an onset of the ground fault current at the selected level, and a time when the ground fault interrupter tripped.

2. The process of claim 1, wherein

the one or more power lines is a plurality of power lines, and

the process further comprises performing the selecting, generating, setting, repeating, and reporting for one or more power lines other than the first power line.

3. The process of claim 1 wherein:

the plurality of current levels includes at least one current level less than a specified minimum trip current of the ground fault interrupter and at least one current level greater than the minimum trip current.

4. The process of claim 1, wherein at least one of the on-time intervals associated with the plurality of current levels is different from the others.

5. The process of claim 1, wherein at least one of the off-time intervals associated with the plurality of current levels is different from the others.

6. An apparatus for performing a ground fault test of a device that derivers power to a load via one or more power lines, the apparatus comprising:

a first controllable current generator connected to generate a first ground fault current between ground and a first power line of the one or more power lines; and

a controller coupled to the first controllable current generator, wherein the controller is programmed to perform or cause to be performed, the following actions;

selecting a current level sourced by the first controllable current generator, from a plurality of different current levels;

controlling the first controllable current generator to generate a ground fault current at the selected current level until a ground fault interrupter within the device trips in response to the ground fault current, or until expiration of an on-time interval associated with the selected current level, whichever occurs first;

after controlling the first controllable current generator to generate a ground fault current at the selected current level, controlling the first controllable current generator to set the ground fault current to zero for an off-time interval associated with the selected current level, and

repeating the selecting and controlling actions for each of the plurality of current levels, wherein;

the controller is further programmed to perform, or cause to be performed, the following actions;

when the ground fault interrupter within the device trips, reporting the selected current level at which the ground fault interrupter tripped, and a time interval from an onset of the ground fault current at the selected level, and a time when the ground fault interrupter tripped.

7. The apparatus of claim 6 wherein:

the plurality of current levels include at least one current level less than a specified minimum trip current of the ground fault interrupter and at least one current level greater than the minimum trip current.

8. The apparatus of claim 6, wherein one of the on-time intervals associated with the plurality of current levels is different from the others.

9. The apparatus of claim 6 wherein at least one of the off-time intervals associated with the plurality of current levels is different from the others.

10. The apparatus of claim 6, wherein the controller further comprises:

a processor;

non-transitory storage coupled to the processor, the non-transitory storage storing instructions that, when executed by the processor, cause the controller to perform the selecting, controlling repeating, and reporting actions.

11. The apparatus of claim 6, further comprising:

a second controllable current generator connected to generate a second ground fault current between ground and a second power line of the plurality of power lines, wherein the controller is coupled to the second controllable current generator and configured to perform actions including;

selecting a current level sourced by the second controllable current generator, from a plurality of different current levels;

controlling the second controllable current generator to generate a ground fault current at the selected current level until a ground fault interrupter within the device trips in response to the ground fault current, or until expiration of the on-time period associated with the selected current level, whichever occurs first;

after controlling the second controllable current generator to generate a ground fault current at the selected current level, controlling the second controllable current generator to set the ground fault current to zero for the off-time interval associated with the selected current level, and

repeating the selecting and controlling actions for each of the plurality of current levels, wherein;

the controller is further programmed to perform, or cause to be performed, the following actions;

when the ground fault interrupter within the device trips, reporting the selected current level at which the ground fault interrupter tripped, and a time interval from an onset of the ground fault current at the selected level, and a time when the ground fault interrupter tripped.