Methods and apparatus for operating electric vehicles

• US 20040239288A1
• Filed: 05/29/2003
• Published: 12/02/2004
• Est. Priority Date: 05/29/2003
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Meyer, Brian Nedward, Harrison, John Springer
• Granted Patent: US 6,917,180 B2
• Time in Patent Office: Days
• US Class Current: 320/104
• CPC Class Codes: B60L 2200/22 Microcars, e.g. golf cars
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 7/12 for vehicles propelled by dc motors
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A method of controlling electrical energy in a battery-powered vehicle wherein the vehicle includes a battery and a traction motor is provided. The method includes electrically coupling an external source of electrical energy to a unitary, integrated traction motor controller/vehicle battery charge controller positioned on-board the vehicle, controlling electrical energy flow to a vehicle battery with the unitary, integrated traction motor controller/vehicle battery charge controller during a charging period, and controlling electrical energy flow to a vehicle traction motor that is operable to propel the vehicle with the unitary, integrated traction motor controller/vehicle battery charge controller during a transport period.

Claims

1. A method of controlling electrical energy in a battery-powered vehicle, the vehicle including a battery and a traction motor, said method comprising:

electrically coupling an external source of electrical energy to a unitary, integrated traction motor controller/vehicle battery charge controller positioned on-board the vehicle;

controlling electrical energy flow to the battery with the unitary, integrated traction motor controller/vehicle battery charge controller during a charging period; and

controlling electrical energy flow to the traction motor, that is operable to propel the vehicle, with the unitary, integrated traction motor controller/vehicle battery charge controller during a transport period.

2. A method in accordance with claim 1 wherein electrically coupling an external source of electrical energy to a unitary, integrated traction motor controller/vehicle battery charge controller comprises electrically coupling a source of direct current electrical energy from a battery charger.

3. A method in accordance with claim 2 wherein electrically coupling an external source of electrical energy to a unitary, integrated traction motor controller/vehicle battery charge controller comprises electrically coupling a signal path between the motor controller/vehicle battery charge controller and the battery charger.

4. A method in accordance with claim 1 wherein controlling electrical energy flow to the vehicle battery comprises regulating at least one of a voltage output and a current output of the source of electrical energy using the integrated traction motor controller/vehicle battery charge controller.

5. A method in accordance with claim 4 wherein regulating at least one of a voltage output and a current output of the source of electrical energy comprises regulating at least one of a voltage output and a current output of the source of electrical energy based on at least one of a battery state of charge and a predetermined charging program.

6. A method in accordance with claim 1 further comprising regeneratively braking the vehicle using integrated traction motor controller/vehicle battery charge controller such that electrical energy produced during braking is returned to the battery.

7. A method in accordance with claim 6 wherein regeneratively braking the vehicle comprises controlling an over speed of the vehicle.

8. A method in accordance with claim 6 wherein regeneratively braking the vehicle comprises limiting a top speed of the vehicle to a predetermined level.

9. A method in accordance with claim 1 further comprising:

plug braking the vehicle using the integrated traction motor controller/vehicle battery charge controller for detecting a zero speed condition; and

utilizing a plug braking circuit to at least one of alerting an operator that an unattended vehicle is moving, and slowing down the vehicle when changing vehicle direction of travel.

10. A unitary, integrated traction motor controller/vehicle battery charge controller (OBC) for controlling electrical energy flow in a battery-powered electric vehicle, wherein the vehicle includes a traction motor and a battery for supplying electrical energy to said traction motor, said OBC comprising:

a shunt motor controller mounted within an electrical panel;

a battery charge controller mounted within said electrical panel; and

a microprocessor operable with said shunt motor controller to control said traction motor during motoring, braking, and standing periods, said microprocessor operable with said battery charge controller to control a battery charging rate during a charging period.

11. An OBC in accordance with claim 10 wherein said traction motor comprises a field winding and an armature winding, said shunt motor controller comprises:

a DC chopper control for control of said motor armature winding; and

a H-bridge configuration for controlling said motor field winding electrically coupled to said traction motor field winding.

12. An OBC in accordance with claim 10 wherein said battery charge controller is configured to control a rate of return of energy to said battery based on a state of charge of said battery, said battery charge controller comprises:

a rectifier; and

a current measuring device at least one of magnetically coupled, and electrically coupled to a battery-current carrying conductor.

13. An OBC in accordance with claim 12 wherein said rectifier is an SCR.

14. An OBC in accordance with claim 10 further comprising:

a power supply circuit mounted within said electrical panel, said power supply circuit electrically coupled to said shunt motor controller and said battery charge controller; and

an under voltage circuit mounted within said electrical panel, said under voltage circuit electrically coupled to said shunt motor controller and said battery charge controller.

15. A battery-operated vehicle comprising:

a traction motor;

a battery for supplying electrical energy to said motor;

a battery charge controller electrically coupled to said battery;

an electrical connector configured to electrically couple to an external battery charger and to at least one of said battery and said battery charge controller during a charging period; and

a motor controller electrically coupled to said motor, said motor controller operable to control current flow to said motor;

said battery charge controller and said motor controller are mounted in a single enclosure, said battery charge controller and said motor controller are integrated to be controlled by a single microcontroller mounted within said enclosure.

16. A vehicle in accordance with claim 15 wherein said microcontroller is operable to control said motor controller and disable said battery charge controller, and to control said battery charge controller and disable said motor controller.

17. A vehicle in accordance with claim 15 wherein said battery charge controller comprises a charging current sensor.

18. A vehicle in accordance with claim 15 wherein said motor controller comprises a motor current sensor.

19. A vehicle in accordance with claim 15 wherein said microcontroller is programmed to determine a state of charge of said battery from a battery discharge history of said battery.

20. A vehicle in accordance with claim 19 wherein said microcontroller is programmed to control said battery change controller to optimize a charging rate and duration based on the state of charge of said battery.