HYBRID VEHICLE AND CONTROL METHOD THEREOF

• US 20100138090A1
• Filed: 10/25/2007
• Published: 06/03/2010
• Est. Priority Date: 12/28/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yaguchi, Hideaki, Maeda, Masahiko, Jinno, Kunihiko, Nakagawa, Tadashi
• Granted Patent: US 8,204,639 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: B60K 6/448 Electrical distribution type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 15/2054 by controlling transmissions or clutches
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/52 Clutch motors
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2250/24 : by lever actuation
• CPC Class Codes: B60L 2250/26 : by pedal actuation
• CPC Class Codes: B60L 2260/28 : Four wheel or all wheel drive
• CPC Class Codes: B60L 50/16 : with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 : by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/12 : responding to state of charge [SoC]
• CPC Class Codes: B60L 58/20 : having different nominal voltages
• CPC Class Codes: B60W 10/04 : including control of propulsion units
• 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 20/00 : Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 : Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2540/215 : Selection or confirmation of options
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: B60W 30/18 : Propelling the vehicle
• CPC Class Codes: B60W 40/09 : Driving style or behaviour
• CPC Class Codes: B60W 50/082 : Selecting or switching between different modes of propelling
• CPC Class Codes: B60W 50/085 : Changing the parameters of the control units, e.g. changing limit values, working points by control input
• CPC Class Codes: F02D 29/02 : peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration

Abstract

In a hybrid vehicle 20, an engine 22, motors MG1 and MG2 are controlled so that the engine 22 is operated at a target operation point set at Step 120 based on a torque demand Tr* and the motor MG2 outputs lower power for driving in comparison with a turn-off condition of an ECO switch 88 when the ECO switch 88 is turned on upon driving with power from both the engine 22 and the motor MG2 (Steps S130-S150 and S170-S200).

Claims

1. A hybrid vehicle comprising:

an internal combustion engine capable of outputting power for driving;

a motor capable of outputting power for driving;

an accumulator capable of supplying and receiving electric power from the motor;

an efficiency priority mode selection switch to select an efficiency priority mode that gives priority to energy efficiency;

a driving force demand setting module configured to set a driving force demand required for driving the hybrid vehicle;

a target operation point setting module configured to set a target operation point of the internal combustion engine based on the set driving force demand; and

a control module configured to control the internal combustion engine and the motor so that the internal combustion engine is operated at the set target operation point and a driving power equivalent to the set driving force demand is ensured when the efficiency priority mode selection switch is turned off upon driving with power from both the internal combustion engine and the motor, the control module controlling the internal combustion engine and the motor so that the internal combustion engine is operated at the set target operation point and the motor outputs lower power for driving in comparison with a turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

2. A hybrid vehicle according to claim 1, wherein the control module sets a torque command value for the motor to be smaller by a predetermined amount than that of the turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

3. A hybrid vehicle according to claim 1, further comprising:

a power transmitting mechanism having an axle-side rotational element connected to a predetermined axle, and an engine-side rotational element connected to an engine shaft of the internal combustion engine and configured to differentially rotate with respect to the axle-side rotational element, the power transmitting mechanism capable of outputting at least a part of power from the engine shaft to the axle side.

4. A hybrid vehicle according to claim 3, wherein the power transmitting mechanism is an electric power-mechanical power input output structure connected to the predetermined axle and the engine shaft of the internal combustion engine and outputting at least apart of power from the internal combustion engine to the axle side with input/output of electric power and mechanical power, the electric power-mechanical power input output structure supplying and receiving electric power from the accumulator.

5. A hybrid vehicle according to claim 4, wherein the electric power-mechanical power input output structure includes a power generation motor capable of inputting and outputting power, and a three shaft-type power input output assembly connected with three shafts, the predetermined axle, the engine shaft of the internal combustion engine, and a rotating shaft of the power generation motor, the three shaft-type power input output assembly configured to input and output power to one remaining shaft, based on input and output of powers from and to any two shafts selected among the three shafts.

6. A hybrid vehicle according to claim 5, wherein the control module sets a torque command value for the motor so that electric power supplied to the motor from the accumulator becomes smaller by a predetermined rate than that of the turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

7. A hybrid vehicle according to claim 3, wherein the power transmitting mechanism is a continuously variable transmission.

8. A control method of a hybrid vehicle including an internal combustion engine capable of outputting power for driving, a motor capable of outputting power for driving, an accumulator capable of supplying and receiving electric power from the motor, and an efficiency priority mode selection switch to select an efficiency priority mode that gives priority to energy efficiency, the method comprising the steps of:

(a) setting a target operation point of the internal combustion engine based on a driving force demand required for driving the hybrid vehicle; and

(b) controlling the internal combustion engine and the motor so that the internal combustion engine is operated at the target operation point set at the step (a) and a driving power equivalent to the set driving force demand is ensured when the efficiency priority mode selection switch is turned off upon driving with power from both the internal combustion engine and the motor, and controlling the internal combustion engine and the motor so that the internal combustion engine is operated at the target operation point set at the step (a) and the motor outputs lower power for driving in comparison with a turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

9. A control method of a hybrid vehicle according to claim 8, wherein the step (b) sets a torque command value for the motor to be smaller by a predetermined amount than that of the turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

10. A control method of a hybrid vehicle according to claim 8, wherein the hybrid vehicle further includes a power transmitting mechanism having an axle-side rotational element connected to a predetermined axle, and an engine-side rotational element connected to an engine shaft of the internal combustion engine and configured to differentially rotate with respect to the axle-side rotational element, the power transmitting mechanism capable of outputting at least a part of power from the engine shaft to the axle side.

11. A control method of a hybrid vehicle according to claim 10, wherein the power transmitting mechanism is an electric power-mechanical power input output structure connected to the predetermined axle and the engine shaft of the internal combustion engine and outputting at least a part of power from the internal combustion engine to the axle side with input/output of electric power and mechanical power, the electric power-mechanical power input output structure supplying and receiving electric power from the accumulator.

12. A control method of a hybrid vehicle according to claim 11, wherein the electric power-mechanical power input output structure includes a power generation motor capable of inputting and outputting power, and a three shaft-type power input output assembly connected with three shafts, the predetermined axle, the engine shaft of the internal combustion engine, and a rotating shaft of the power generation motor, the three shaft-type power input output assembly configured to input and output power to one remaining shaft, based on input and output of powers from and to any two shafts selected among the three shafts.

13. A control method of a hybrid vehicle according to claim 12, wherein the step (b) sets a torque command value for the motor so that electric power supplied to the motor from the accumulator becomes smaller by a predetermined rate than that of the turn-off condition of the efficiency priority mode selection switch when the efficiency priority mode selection switch is turned on upon driving with power from both the internal combustion engine and the motor.

14. A control method of a vehicle according to claim 11, wherein the power transmitting mechanism is a continuously variable transmission.