Vehicle drive control apparatus and method

• US 20060276289A1
• Filed: 06/02/2006
• Published: 12/07/2006
• Est. Priority Date: 06/03/2005
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Hirata, Takeshi, Yamanaka, Tsuyoshi
• Granted Patent: US 7,650,956 B2
• Time in Patent Office: Days
• US Class Current: 475/5
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 28/165 acting on elements of the vehicle drive train other than the propulsion unit and brakes, e.g. transmission, clutch, differential acting on brakes B60T8/17
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/115 with planetary gears
• 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 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2520/26 Wheel slip
• CPC Class Codes: F16H 2037/088 Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• CPC Class Codes: F16H 2037/102 the input or output shaft of the transmission is connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/104 Power split variators with one end of the CVT connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/106 with switching means to provide two variator modes or ranges
• CPC Class Codes: F16H 2061/0239 Selecting ratios for preventing or cancelling wheel slip
• CPC Class Codes: F16H 2200/201 with three sets of orbital gears
• CPC Class Codes: F16H 3/728 with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A vehicle drive control for a wheeled vehicle including a first motor generator, and a second motor generator. A planetary gear set includes a first rotating element connected to the first motor generator, a second rotating element connected to the second motor generator, and a third rotating element connected to a drive wheel. A rotation control mechanism selectively restricts rotation of one of the first and second rotating elements of the planetary gear set to establish a fixed speed ratio mode, and releases the one of the first and second rotating elements to establish a variable speed ratio mode. A control unit is configured to control each operating state of the rotation control mechanism, the first motor generator, and the second motor generator, and configured to establish the variable speed ratio mode when a slip state of the drive wheel is detected in the fixed speed ratio mode.

Claims

1. A vehicle drive control apparatus for a wheeled vehicle including a first motor generator, and a second motor generator, the vehicle drive control apparatus comprising:

a planetary gear set including a first rotating element adapted to be drivingly connected to the first motor generator, a second rotating element adapted to be drivingly connected to the second motor generator, and a third rotating element adapted to be drivingly connected to a drive wheel of the vehicle;

a rotation control mechanism adapted selectively to restrict rotation of one of the first and second rotating elements of the planetary gear set to establish a fixed speed ratio mode, and to release the one of the first and second rotating elements to establish a variable speed ratio mode;

a wheel slip detector configured to detect a slip state of the drive wheel with respect to a road surface; and

a control unit configured to control each operating state of the rotation control mechanism, the first motor generator, and the second motor generator,

the control unit being configured to establish the variable speed ratio mode when the slip state of the drive wheel is detected in the fixed speed ratio mode.

2. The vehicle drive control apparatus as claimed in claim 1, wherein a speed ratio of the third rotating element of the planetary gear set to the other of the first and second rotating elements of the planetary gear set is fixed in the fixed speed ratio mode, and

wherein the speed ratio is allowed to vary in the variable speed ratio mode.

3. The vehicle drive control apparatus as claimed in claim 1, wherein the vehicle includes an engine,

wherein the planetary gear set includes a fourth rotating element adapted to be drivingly connected to the engine, wherein a speed ratio of the third rotating element of the planetary gear set to the fourth rotating element of the planetary gear set is fixed in the fixed speed ratio mode, and

wherein the speed ratio is allowed to vary in the variable speed ratio mode.

4. The vehicle drive control apparatus as claimed in claim 1, wherein the rotation control mechanism is a brake adapted selectively to hold stationary one of the first and second rotating elements of the planetary gear set to establish the fixed speed ratio mode, and to release the one of the first and second rotating elements to establish the variable speed ratio mode.

5. The vehicle drive control apparatus as claimed in claim 1, wherein the wheel slip detector is configured to detect a braking slip state of the drive wheel with respect to a road surface, and

wherein the control unit is configured to establish the variable speed ratio mode when the braking slip state of the drive wheel is detected in the fixed speed ratio mode, and configured to control the first and second motor generators in such a manner to apply a braking effort to the drive wheel in the established variable speed ratio mode.

6. The vehicle drive control apparatus as claimed in claim 1, wherein the wheel slip detector is configured to detect a driving slip state of the drive wheel with respect to a road surface, and

wherein the control unit is configured to establish the variable speed ratio mode when the driving slip state of the drive wheel is detected in the fixed speed ratio mode, and configured to control the first and second motor generators in such a manner to apply a driving effort to the drive wheel in the established variable speed ratio mode.

7. The vehicle drive control apparatus as claimed in claim 1, further comprising a wheel slip controller configured to control the slip state of the drive wheel in accordance with a desired slip state when the slip state of the drive wheel is detected,

wherein the control unit is configured to inhibit establishment of the fixed speed ratio mode for a predetermined period of time after a control process of the wheel slip controller is completed in the established variable speed ratio mode.

8. A vehicle drive control apparatus for a wheeled vehicle including an engine, a first motor generator, and a second motor generator, the vehicle drive control apparatus comprising:

a case;

a first single-pinion planetary gear comprising a first sun gear, a first planet-pinion carrier, and a first ring gear;

a second single-pinion planetary gear comprising a second sun gear, a second planet-pinion carrier, and a second ring gear;

a third single-pinion planetary gear comprising a third sun gear, a third planet-pinion carrier, and a third ring gear, the third planet-pinion carrier being drivingly connected to a drive wheel of the vehicle;

a first rotating member coupling the first sun gear and the second sun gear, the first rotating member being drivingly connected to the second motor generator;

a second rotating member coupling the first ring gear and the third sun gear;

a third rotating member coupling the second planet-pinion carrier and the third ring gear;

a first clutch selectively and drivingly connecting and disconnecting the engine and the first motor generator;

a second clutch selectively and drivingly connecting and disconnecting the second ring gear and the first motor generator;

a third clutch selectively and drivingly connecting and disconnecting the first planet-pinion carrier and the second motor generator;

a fourth clutch selectively and drivingly connecting and disconnecting the third rotating member and the engine;

a first brake selectively and drivingly connecting and disconnecting the second ring gear and the case;

a second brake selectively and drivingly connecting and disconnecting the first planet-pinion carrier and the case;

a wheel slip detector configured to detect a slip state of the drive wheel with respect to a road surface; and

a control unit configured to control each operating state of the first, second, third, and fourth clutches, the first and second brakes, and the first and second motor generators to establish at least a fixed speed ratio mode in which a speed ratio of the third planet-pinion carrier to the third rotating member is fixed and at least a variable speed ratio mode in which the speed ratio is allowed to vary,

the control unit being configured to establish the at least a variable speed ratio mode when the slip state of the drive wheel is detected in the at least a fixed speed ratio mode.

9. The vehicle drive control apparatus as claimed in claim 8, wherein a first fixed speed ratio mode is established by disengaging the first clutch, engaging the second clutch, disengaging the third clutch, disengaging the fourth clutch, engaging the first brake, and engaging the second brake, and

wherein the control unit is configured to establish a first variable speed ratio mode by disengaging the first brake when the slip state of the drive wheel is detected in the first fixed speed ratio mode.

10. The vehicle drive control apparatus as claimed in claim 8, wherein a second fixed speed ratio mode is established by disengaging the first clutch, engaging the second clutch, engaging the third clutch, disengaging the fourth clutch, disengaging the first brake, and engaging the second brake, and

wherein the control unit is configured to establish a second variable speed ratio mode by disengaging the second brake when the slip state of the drive wheel is detected in the second fixed speed ratio mode.

11. The vehicle drive control apparatus as claimed in claim 8, wherein a third fixed speed ratio mode is established by disengaging the first clutch, engaging the second clutch, disengaging the third clutch, engaging the fourth clutch, engaging the first brake, and engaging the second brake, and

wherein the control unit is configured to establish a third variable speed ratio mode by disengaging the first brake when the slip state of the drive wheel is detected in the third fixed speed ratio mode.

12. The vehicle drive control apparatus as claimed in claim 8, wherein a fourth fixed speed ratio mode is established by disengaging the first clutch, engaging the second clutch, engaging the third clutch, engaging the fourth clutch, disengaging the first brake, and engaging the second brake, and

wherein the control unit is configured to establish a fourth variable speed ratio mode by disengaging the second brake when the slip state of the drive wheel is detected in the fourth fixed speed ratio mode.

13. A vehicle drive control apparatus for a wheeled vehicle including a first motor generator, and a second motor generator, the vehicle drive control apparatus comprising:

a planetary gear set including a first rotating element adapted to be drivingly connected to the first motor generator, a second rotating element adapted to be drivingly connected to the second motor generator, and a third rotating element adapted to be drivingly connected to a drive wheel of the vehicle;

rotation control means for selectively restricting rotation of one of the first and second rotating elements of the planetary gear set to establish a fixed speed ratio mode, and releasing the one of the first and second rotating elements to establish a variable speed ratio mode;

wheel slip detecting means for detecting a slip state of the drive wheel with respect to a road surface; and

control means for controlling each operating state of the rotation control mechanism, the first motor generator, and the second motor generator,

the control means being configured to establish the variable speed ratio mode when the slip state of the drive wheel is detected in the fixed speed ratio mode.

14. A vehicle drive control method for a wheeled vehicle including a first motor generator, a second motor generator, a planetary gear set including a first rotating element adapted to be drivingly connected to the first motor generator, a second rotating element adapted to be drivingly connected to the second motor generator, and a third rotating element adapted to be drivingly connected to a drive wheel of the vehicle, and a rotation control mechanism adapted selectively to restrict rotation of one of the first and second rotating elements of the planetary gear set to establish a fixed speed ratio mode, and to release the one of the first and second rotating elements to establish a variable speed ratio mode, the vehicle drive control method comprising:

controlling each operating state of the rotation control mechanism, the first motor generator, and the second motor generator;

detecting a slip state of the drive wheel with respect to a road surface; and

establishing the variable speed ratio mode when the slip state of the drive wheel is detected in the fixed speed ratio mode.