VEHICLE INTERFACE WITH NON-LOCAL RETURN TO GROUND

• US 20130175988A1
• Filed: 02/14/2012
• Published: 07/11/2013
• Est. Priority Date: 01/06/2012
• Status: Active Grant

• Current Assignee: Lear Corporation
• Original Assignee: Lear Corporation
• Inventors: Ghabbour, Youssef, Acea, Miguel Angel
• Granted Patent: US 9,248,748 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 53/18 Cables specially adapted for charging electric vehicles
• CPC Class Codes: H01H 1/00 Contacts liquid contacts H01H29/04
• CPC Class Codes: H02H 1/00 Details of emergency protective circuit arrangements
• 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

Abstract

A vehicle interface is contemplated to be operable with an Electronic Vehicle Supply Equipment (EVSE) system and a vehicle charging system to facilitate vehicle charging related operations. The vehicle interface may include a noise compensation configured to facilitate compensating for noise within the reference signal resulting from the reference circuit. The vehicle interface may be configured to adapted to common mode interference and other influences resulting from connections between the vehicle interface and EVSE being referenced to earth ground and connections between the vehicle interface and other vehicle electronics being reference to a vehicle chassis ground.

Claims

1. A vehicle charging system operable with an Electronic Vehicle Supply Equipment (EVSE) system configured to facilitate powering a charger power plant within a vehicle, the charger power plant configured to facilitate charging a high voltage battery included within the vehicle, the vehicle having a low voltage battery with a positive terminal and a negative terminal where the negative terminal defines a vehicle chassis ground, the system comprising:

a reference circuit configured to receive a control pilot signal output from the EVSE, the reference circuit processing the control pilot signal to generate reference signals;

a shunt configured to connect the reference circuit in series with the vehicle chassis ground; and

a charger controller operable to output a control signal to the charger power plant, the charger power plant relying on the control signal to facilitate controlling the charging of the high voltage battery, the charger controller generating the control signal by processing the reference signals with a compensation device, the compensation device compensating for noise within the reference signal resulting from the reference circuit being connected in series with the shunt.

2. The system of claim 1 wherein the charger controller includes a first input measurement node and a second input measurement node, the reference signals corresponding with signals measured at the first and second input measurement nodes.

3. The system of claim 2 wherein the compensation device includes a differential amplifier configured to output a subtracted signal, the charger controller processing the subtracted signal to generate the control signal.

4. The system of claim 3 wherein the differential amplifier is configured to subtract the reference signals measured at one of the first and second input measurement nodes from the reference signals measured at the other one of the first and second measurement nodes, the subtraction compensating for common mode noise resulting from the reference circuit being connected in series with the shunt.

5. The system of claim 4 wherein the reference circuit has a reference circuit ground equal to an earth ground of the EVSE system.

6. The system claim 5 wherein the shunt forces the reference circuit ground to be greater than the vehicle chassis ground.

7. The system claim 6 wherein the differential amplifier bypasses the shunt to be grounded directly to the vehicle chassis ground.

8. The system of claim 3 wherein the charger controller includes a voltage follower and peak detection unit configured to generate the control signal from the subtracted signal.

9. The system of claim 8 wherein the voltage follower and peak detection unit is configured to generate a first reference voltage in the event a voltage of the subtracted signal is greater than a threshold and to generate a second reference voltage in the event the voltage of the subtracted signal is less than the threshold, the control signal reflecting the first and second reference voltages, the charger power plant being able to charge the high voltage battery when the first reference voltage is determined in being prevented from charging the high voltage battery when the second reference voltage is determined.

10. The system of claim 3 wherein the charger controller includes a level-shifter configured to generate the control signal from the subtracted signal.

11. The system of claim 10 wherein the level-shifter is configured to extract data from the subtracted signal, the control signal reflecting the extracted data for use by the charger power plant in determining a maximum current level for the charging of the high voltage battery.

12. The system of claim 1 wherein the reference circuit includes:

a control pilot input operable to receive the control pilot signal of the EVSE system;

an earth ground input operable to connect to an earth ground of the EVSE system;

a first resistor connected in series between the control pilot input and the earth ground input;

a first switch, a second resistor, and a second switch connected in series and in parallel to the first resistor, the first and second switches each being independently operable between an open position and a closed position according to corresponding first and second switch signals received from the charger controller.

13. The system of claim 12 wherein the charger controller includes:

a first driver for generating the first switch signal for controlling the first switch between the open and closed positions;

a second driver for generating the second switch signal for controlling the second switch between the open and closed positions; and

wherein the first and second drivers bypass to shunt to be connected directly to the vehicle chassis ground.

14. The system of claim 13 further comprising a power supply for powering the first and second drivers, the power supply bypassing the shunt to be connected directly to the vehicle chassis ground.

15. A charger controller operable with a reference circuit, the reference circuit being connected in series with a shunt to a vehicle chassis ground of a vehicle, the reference circuit being configured to generate reference signals in response to receipt of a control pilot signal from an Electronic Vehicle Supply Equipment (EVSE) system, the EVSE system being configured to facilitate powering a charger power plant included within a vehicle to charge a high voltage battery within the vehicle, the reference circuit having a control pilot input operable to receive the control pilot signal of the EVSE system and an earth ground input operable to connect to an earth ground of the EVSE system, the reference circuit further including a first resistor connected in series between the control pilot input and the earth ground input, the reference circuit further including a first switch, a second resistor, and a second switch connected in series and in parallel to the first resistor, the first and second switches each being independently operable between an open position and a closed position, the charger controller comprising:

a compensation device operable to process the reference signals into a charger control signal, the charger control signal for use with the charger power plant to facilitate controlling the charging of the high voltage battery, the compensation device being configured to limit noise the charger control signal by compensating for noise within the reference signals.

16. The charger controller of claim 15 wherein the compensation device as a non-local ground to the reference circuit.

17. The charger controller claim 16 wherein the compensation device includes a differential amplifier configured to subtract reference signals measured at one of a first and second input measurement node of the reference circuit from reference signals measured at the other one of the first and second measurement node, the subtraction compensating for common mode noise within the reference signals resulting from the reference circuit being connected in series with the shunt, the charger controller processing the subtracted signal to generate the control signal.

18. The charger controller of claim 15 further comprising

a first driver for controlling the first switch between the open and closed positions;

a second driver for controlling the second switch between the open and closed positions; and

a power supply for powering the first and second drivers, the power supply bypassing the shunt to be connected directly to the vehicle chassis ground.

19. A vehicle charging system operable with an Electronic Vehicle Supply Equipment (EVSE) system configured to facilitate powering a charger power plant within a vehicle, the charger power plant configured to facilitate charging a high voltage battery included within the vehicle, the vehicle having a low voltage battery with a positive terminal and a negative terminal where the negative terminal defines a vehicle chassis ground, the EVSE having an earth ground, the system comprising:

a reference circuit configured to receive a control pilot signal output from the EVSE, the reference circuit processing the control pilot signal to generate reference signals, the reference circuit being connected in series through a shunt to the vehicle chassis ground, the reference circuit including

i) a control pilot input operable to receive the control pilot signal of the EVSE system;

ii) an earth ground input operable to connect to an earth ground of the EVSE system;

iii) a first resistor connected in series to the control pilot input, the earth ground input, the shunt, and the vehicle chassis ground;

iv) a first switch, a second resistor, and a second switch connected in series to the control pilot input, the earth ground input, the shunt, and the vehicle chassis ground and in parallel to the first resistor, the first and second switches each being independently operable between an open position and a closed position according to corresponding first and second switch signals; and

a charger controller operable to output a control signal to the charger power plant to the charger power plant and to output the first and second switch signals to the first and second switches, the charger power plant relying on the control signal to facilitate controlling the charging of the high voltage battery, the charger controller generating the control signal by processing the reference signals with a compensation device, the compensation device compensating for noise within the reference signal resulting from the reference circuit being connected in series with the shunt.

20. The system of claim 19 wherein the compensation device includes a differential amplifier configured to subtract reference signals measured at one of a first and second input measurement node of the reference circuit from reference signals measured at the other one of the first and second measurement node, the subtraction compensating for common mode noise within the reference signals resulting from the reference circuit being connected in series with the shunt, the charger controller processing the subtracted signal to generate the control signal.