Drive control system for electric vehicle and method of drive control of electric vehicle

• US 20050159861A1
• Filed: 12/03/2004
• Published: 07/21/2005
• Est. Priority Date: 01/21/2004
• Status: Active Grant

• Current Assignee: Aisin AW Company Limited (Aisin Corp.)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.)
• Inventors: Iwatsuki, Ken, Nomura, Masaki
• Granted Patent: US 7,496,435 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 2710/081 Speed
• CPC Class Codes: B60W 2710/105 Output torque
• CPC Class Codes: F16H 63/483 Circuits for controlling engagement of parking locks or brakes
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A drive control system for an electric vehicle and a method of drive control of the electric vehicle. The drive control system for the electric vehicle includes a drive motor target torque calculation processing device for calculating a drive motor target torque representing a target torque of a drive motor; and a drive motor target torque restriction processing device that judges whether or not a parking mechanism is in operation and, if the parking mechanism is in operation, restricts variations in the drive motor target torque.

Claims

1. A drive control system for an electric vehicle comprising:

a drive motor target torque calculation processing device for calculating a drive motor target torque representing a target torque of a drive motor; and

a drive motor target torque restriction processing device that determines whether or not a parking mechanism provided engageably and disengageably with respect to a drive shaft so as to disable rotation of the drive shaft is in operation and, if the parking mechanism is in operation, restricts variations in the drive motor target torque.

2. A drive control system for an electric vehicle according to claim 1, wherein the drive motor target torque restriction processing device restricts a rate of change of the drive motor target torque.

3. A drive control system for an electric vehicle according to claim 1, further comprising a vibration restriction processing device that calculates a torque correction value for the drive motor target torque in order to restrict vibrations of a vehicle output shaft of the electric vehicle, wherein the drive motor target torque restriction processing device restricts the torque correction value.

4. A drive control system for an electric vehicle according to claim 3, further comprising a drive motor angular acceleration calculation processing device for calculating an angular acceleration of the drive motor,

wherein the vibration restriction processing device calculates a torque correction value so that the angular acceleration becomes smaller than a predetermined value.

5. A drive control system for an electric vehicle according to claim 3, further comprising a plurality of detecting units disposed at predetermined positions on a plurality of shafts, kinds of the plurality of shafts comprise at least one of the vehicle output shaft, the drive shaft, a transmission shaft, and a counter shaft,

wherein the vibration restriction processing device calculates the torque correction value so that a difference in revolution number detected by the respective detecting units becomes zero.

6. A drive control system for an electric vehicle according to claim 1, wherein the drive motor target torque restriction, processing device restricts a rate of change of the drive motor target torque so as to be smaller than in a state in which the parking mechanism is not in operation.

7. A drive control system for an electric vehicle according to claim 6, further comprising a vibration restriction processing device that calculates a torque correction value for the drive motor target torque in order to restrict vibrations of a vehicle output shaft of the electric vehicle,

wherein the drive motor target torque restriction processing device restricts the torque correction value.

8. A drive control system for an electric vehicle according to claim 7, further comprising a drive motor angular acceleration calculation processing device for calculating an angular acceleration of the drive motor,

wherein the vibration restriction processing device calculates a torque correction value so that the angular acceleration becomes smaller than a predetermined value.

9. A drive control system for an electric vehicle according to claim 7, further comprising a plurality of detecting units disposed at predetermined positions on a plurality of shafts, kinds of the plurality of shafts comprise at least one of the vehicle output shaft, the drive shaft, a transmission shaft, and a counter shaft,

wherein the vibration restriction processing device calculates the torque correction value so that a difference in revolution number detected by the respective detecting units becomes zero.

10. A drive control system for an electric vehicle according to claim 1, further comprising a differential rotator having a first to a third differential elements, the first differential element being connected to a generator, the second differential element being connected to the drive motor, and the third differential element connected to an engine,

wherein the drive motor target torque restriction processing device is configured so that a generator revolution number is controlled so that an engine revolution number meets an engine target revolution number, the drive motor target torque is calculated so that a vehicle-demanded torque required for causing an electric vehicle to travel based on an engine torque and a generator torque is generated, and variations in the drive motor target torque are restricted when the drive motor is driving.

11. A drive control system for an electric vehicle according to claim 10, further comprising a vibration restriction processing device that calculates a torque correction value for the drive motor target torque in order to restrict vibrations of a vehicle output shaft of the electric vehicle,

wherein the drive motor target torque restriction processing device restricts the torque correction value.

12. A drive control system for an electric vehicle according to claim 11, further comprising a drive motor angular acceleration calculation processing device for calculating an angular acceleration of the drive motor,

wherein the vibration restriction processing device calculates a torque correction value so that the angular acceleration becomes smaller than a predetermined value.

13. A drive control system for an electric vehicle according to claim 11, further comprising a plurality of detecting units disposed at predetermined positions on a plurality of shafts, kinds of the plurality of shafts comprises at least one of the vehicle output shaft, the drive shaft, a transmission shaft, and a counter shaft,

wherein the vibration restriction processing device calculates the torque correction value so that a difference in revolution number detected by the respective detecting units becomes zero.

14. A drive control system for an electric vehicle according to claim 1, further comprising a vibration restriction processing device that calculates a torque correction value for the drive motor target torque in order to restrict vibrations of a vehicle output shaft of the electric vehicle,

wherein the drive motor target torque restriction processing device restricts the torque correction value.

15. A drive control system for an electric vehicle according to claim 14, further comprising a drive motor angular acceleration calculation processing device for calculating an angular acceleration of the drive motor,

wherein the vibration restriction processing device calculates a torque correction value so that the angular acceleration becomes smaller than a predetermined value.

16. A drive control system for an electric vehicle according to claim 14, further comprising a plurality of detecting units disposed at predetermined positions on a plurality of shafts, kinds of the plurality of shafts comprise at least one of the vehicle output shaft, the drive shaft, a transmission shaft and a counter shaft,

wherein the vibration restriction processing device calculates the torque correction value so that a difference in revolution number detected by the respective detecting units becomes zero.

17. A method of drive control of an electric vehicle comprising calculating a drive motor target torque that represents a target torque of a drive motor,

judging whether or not a parking mechanism disposed engageably and disengageably with a drive shaft so as to disable rotation thereof is in operation;

and,

if the parking mechanism is in operation, restricting variations in the drive motor target torque.