Externally referenced scalable auto discharge method for hybrid electric vehicles

• US 9,428,058 B2
• Filed: 07/10/2012
• Issued: 08/30/2016
• Est. Priority Date: 07/10/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Namou, Andrew J., Mackintosh, Todd F.
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): PIGGUSH, AARON C
• Application Number:
  US13/545,748
• Publication Number:
  US 20140015492A1
• Time in Patent Office: 1,512 Days
• Field of Search: 320/136, 320/163, 324/433
• US Class Current: 1/1
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2270/00 Problem solutions or means not otherwise provided for
• CPC Class Codes: B60L 3/0007 Measures or means for preventing or attenuating collisions
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• 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 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• 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

Abstract

A system and method for discharging a high voltage vehicle battery. The system includes a discharge circuit having a reference voltage source providing a reference voltage and a load for discharging the battery. A negative terminal of the voltage source is electrically coupled to a negative terminal of the battery so that upon initiation of the discharging sequence, the battery is discharged through the load to the reference voltage. The discharge circuit can be electrically configured so that the battery, the voltage source and the load are electrically coupled in series or the battery, the voltage source and the load are electrically coupled in parallel.

Claims

1. A discharge circuit for discharging a vehicle battery, said battery including a positive terminal and a negative terminal, said circuit comprising:

a reference voltage source separate from the battery and providing a reference voltage, said voltage source including a negative terminal and a positive terminal, said voltage source being electrically coupled in series with the battery where the negative terminal of the voltage source is electrically coupled to the negative terminal of the battery, where the voltage source is a variable voltage source so that the reference voltage can be changed; and

a load electrically coupled in series with the battery and the voltage source, wherein a current flow through the load generated by the battery discharges the battery to the reference voltage, wherein the voltage source and the load are part of a portable unit that can be selectively electrically coupled to the battery.

2. The circuit according to claim 1 further comprising a switch, said switch being closed to begin discharging of the battery.

3. The circuit according to claim 1 wherein the load is one or more resistors.

4. The circuit according to claim 1 wherein the battery is a high voltage battery having a voltage of 400 volts or more.

5. A discharge circuit for discharging a vehicle battery, said battery including a positive terminal and a negative terminal, said circuit comprising:

a reference voltage source separate from the battery and providing a reference voltage, said voltage source including a negative terminal and a positive terminal, said voltage source being electrically coupled in parallel with the battery where the negative terminal of the voltage source is electrically coupled to the negative terminal of the battery, where the voltage source is a variable voltage source so that the reference voltage can be changed; and

a load electrically coupled in parallel with the battery and the voltage source, wherein a current flow through the load generated by the battery discharges the battery to the reference voltage, wherein the voltage source and the load are part of a portable unit that can be selectively electrically coupled to the battery.