Battery Equalization Using a Plug-In Charger in a Hybrid Electric Vehicle

• US 20090250277A1
• Filed: 06/09/2009
• Published: 10/08/2009
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kuang, Ming L., Syed, Fazal U., Grand, Kerry E., Nallapa, Venkatapathi R.
• Granted Patent: US 8,314,595 B2
• Time in Patent Office: Days
• US Class Current: 180/65.265
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 53/11 DC charging controlled by the charging station, e.g. mode 4
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• 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
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

In a hybrid electric motor vehicle , a power supply system for storing and supplying electrical power includes a motor-generator located onboard the vehicle, driveably connected to the vehicle wheels and producing AC electric power, an energy storage device for alternately storing and discharging electric power, an inverter coupled to the motor-generator and the energy storage device for converting alternating current produced by the motor-generator to direct current transmitted to the energy storage device, and for converting direct current stored in the energy storage device to alternating current transmitted to the motor-generator, an off board source of AC electric power located external to the vehicle, and a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said AC electric power source.

Claims

1. A power supply system for storing and supplying electrical power in a hybrid electric vehicle, comprising:

a motor-generator driveably connected to vehicle wheels for producing AC electric power;

an energy storage device for storing and discharging electric energy;

an internal combustion engine;

a source of AC electric power located external to the vehicle;

a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said electric power source; and

a controller configured to determine a desired magnitude of electric energy with which to charge the energy storage device from energy sources including the engine and motor-generator in combination and the plug-in charger and electric power source in combination, based on a cost of fuel and a cost of electricity provided by the electric power source, and to control a charge supplied to the energy storage device from the energy sources.

2. The system of claim 1 wherein:

the controller is further configured to control equalization of the energy storage device and balancing of individual cells of the energy storage device while charging the energy storage device.

3. In a hybrid electric vehicle that includes an engine, motor-generator, and energy storage device, a power supply system accessible to AC electric power external to the vehicle, the system comprising:

a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said electric power source; and

a controller configured to use a state of charge of the energy storage device and a base electric power profile having regions relating electric power and said state of charge, and to use the motor-generator and internal combustion engine to provide a bulk charge to the energy storage device in accordance with the base electric power profile and a current state of charge.

4. The system of claim 3, wherein said regions comprise a fast active discharge region, a increasing active discharge region, an opportunistic passive region, an increasing active charge and a fast active charge region.

5. The system of claim 3 wherein the controller is further configured to prevent the motor-generator and engine from charging the energy storage device when the region of operation in the base electric energy profile is a fast discharge region.

6. The system of claim 3 wherein the controller is further configured to minimize use of the motor-generator and internal combustion engine for charging the energy storage device when the region of operation in the base electric energy profile is an increasing active discharge region.

7. The system of claim 3 wherein the controller is further configured to prevent the motor-generator and internal combustion engine from discharging the energy storage device when the region of operation in the base electric power profile is a fast charge region.

8. The system of claim 3 wherein the controller is further configured to minimize use of the motor-generator and internal combustion engine for discharging the energy storage device when the region of operation in the base electric power profile is a fast charge region.

9. The system of claim 3 wherein the controller is further configured to use the motor-generator and internal combustion engine for discharging and charging the energy storage device when the region of operation in the base electric power profile is an opportunistic passive region.

10. In a hybrid electric vehicle that includes an engine, motor-generator, and energy storage device, a power supply system accessible to AC electric power external to the vehicle, the system comprising:

a charger coupled to said electric power source and the energy storage device for supplying DC electric power and charging the energy storage device to a first state of charge from said electric power source; and

a controller configured to use, when the vehicle is being driven and high-voltage battery cell voltage equalization is required, the motor-generator and internal combustion to charge the energy storage device to a higher state of charge than the first state of charge in accordance with a modified multiple-region electric power profile relative to a state of charge produced by a base electric power profile.

11. The system of claim 10, wherein said regions comprise a fast active discharge region, a increasing active discharge region, an opportunistic passive region, an increasing active charge and a fast active charge region.

12. The system of claim 10 wherein the controller is further configured to prevent the motor-generator and engine from charging the energy storage device when the region of operation in the modified electric energy profile is a fast discharge region.

13. The system of claim 10 wherein the controller is further configured to minimize use of the motor-generator and internal combustion engine for charging the energy storage device when the region of operation in the modified electric energy profile is an increasing active discharge region.

14. The system of claim 10 wherein the controller is further configured to prevent the motor-generator and internal combustion engine from discharging the energy storage device when the region of operation in the modified electric power profile is a fast charge region.

15. The system of claim 10 wherein the controller is further configured to minimize use of the motor-generator and internal combustion engine for discharging the energy storage device when the region of operation in the modified electric power profile is a fast charge region.

16. The system of claim 10 wherein the controller is further configured to use the motor-generator and internal combustion engine for discharging and charging the energy storage device when the region of operation in the modified electric power profile is an opportunistic passive region.

17. In a hybrid electric vehicle including an engine, a method for operating a power supply system comprising the steps of:

(a) activating energy storage device equalization when the engine is off;

(b) activating energy storage device equalization when a high voltage AC electric power source and a charger are electrically interconnected;

(c) activating energy storage device equalization when a region of operation in a modified electric power profile is an increasing active discharge region or a fast discharge region; and

(d) providing an equalization charge to an energy storage device when a region of operation in the modified electric power profile is the increasing active discharge region or the fast discharge region.

18. In a hybrid electric motor vehicle including an engine and an energy storage device, a method for operating a power supply system for storing and supplying electrical power comprising the steps of:

(a) after a request for energy storage device equalization is unsuccessful, activating engine-based energy storage device equalization to the energy storage device while the engine is running;

(b) activating engine-based energy storage device equalization to the energy storage device when a region of operation in a modified electric power profile is an increasing active discharge region or a fast discharge region; and

(c) providing engine-based equalization charge to the energy storage device in the increasing active discharge region or fast discharge region while energy storage device equalization is being performed.