Vehicle, control method, and computer program

• US 8,903,583 B2
• Filed: 10/20/2011
• Issued: 12/02/2014
• Est. Priority Date: 10/22/2010
• Status: Expired due to Fees

• Current Assignee: HINO Motors Limited (Toyota Motor Corporation)
• Original Assignee: HINO Motors Limited (Toyota Motor Corporation)
• Inventors: Araki, Tomohiko
• Primary Examiner(s): Cheung, Calvin
• Assistant Examiner(s): Martinez Borrero, Luis A
• Application Number:
  US13/813,125
• Publication Number:
  US 20130131903A1
• Time in Patent Office: 1,139 Days
• Field of Search: 701/22, 701/51, 701/54, 701/67, 701/36, 701/68, 701/53, 701/55, 315/131, 477/107, 477/71, 477/2, 477/5, 477/6, 477/8, 904/916, 904/946, 904/912, 904/919, 180/65.265, 180/65.21, 180/65.28, 180/65.281
• US Class Current: 701/22
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/14 Synchronous machines
• 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 2240/507 Operating parameters
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2510/0216 Clutch engagement rate
• CPC Class Codes: B60W 2710/023 Clutch engagement rate
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/081 : Speed
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/085 : Torque change rate
• CPC Class Codes: B60W 30/20 : Reducing vibrations in the driveline
• CPC Class Codes: B60Y 2200/92 : Hybrid vehicles
• 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: Y10S 903/93 : Conjoint control of different elements
• CPC Class Codes: Y10S 903/946 : Characterized by control of driveline clutch

Abstract

The occurrence of shock and the occurrence of the feeling of losing speed can be prevented. When the clutch is engaged from the state in which the clutch is disengaged and a vehicle is being driven by only the power of an electric motor, an electric motor control unit controls the electric motor so that the torque of the electric motor is decreased at a rate determined according to the torque requested by the driver. During the period in which the torque of the electric motor is decreased at the above rate, a clutch control unit controls the engagement of the clutch so that the clutch is engaged after being set to a half-engaged clutch state in which part of the power is transmitted. The present invention is applicable to hybrid vehicles.

Claims

1. A vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power, the vehicle comprising an apparatus including:

electric motor control means for controlling the electric motor that reduces a torque of the electric motor at a rate determined according to a torque requested by a driver when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

clutch engagement control means for controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted and engages the clutch during the period while the torque of the electric motor is reduced at the rate.

2. The vehicle according to claim 1, further comprising:

request means for requesting a synchronization of a rotational speed of the internal combustion engine when the clutch is engaged from the state in which the clutch is disengaged and the vehicle is driven only by the power of the electric motor.

3. The vehicle according to claim 1,

wherein the clutch engagement control means controls the engagement of the clutch to shift the clutch to the half-engaged clutch state where the power is partially transmitted and then engage the clutch if a difference between a rotational speed of the electric motor and the rotational speed of the internal combustion engine is less than a predetermined threshold.

4. A control method of a vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power, the control method comprising:

an electric motor control step for controlling the electric motor that reduces a torque of the electric motor at a rate determined according to a torque requested by a driver when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

a clutch engagement control step for controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted and then engages the clutch during the period while the torque of the electric motor is reduced at the rate.

5. A non-transitory computer-readable storage medium for storing a computer program causing a computer to control a vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power to perform a process including:

an electric motor control step for controlling the electric motor that reduces a torque of the electric motor at a rate determined according to a torque requested by a driver when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

a clutch engagement control step for controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted and then engages the clutch during the period while the torque of the electric motor is reduced at the rate.

6. A vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power, the vehicle comprising:

an Electronic Control Unit (ECU) which controls operation of the an internal combustion engine and an electric motor,

wherein the ECU includes an electric motor control configured to find a torque reducing rate which is determined according to a torque requested by a driver and indicates the rate at which the torque of the electric motor is reduced relative to a time course, and controlling the electric motor that reduces a torque of the electric motor at the torque reducing rate, when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

clutch engagement control means of controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted during a period while the torque of the electric motor is reduced at the torque reducing rate and then engages the clutch.

7. A control method of a vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power, the vehicle comprising an Electronic Control Unit (ECU) for controlling operation of the internal combustion engine and the electric motor, the control method comprising:

an electric motor control step performed by the ECU configured to find a torque reducing rate which is determined according to a torque requested by a driver and indicates the rate at which the torque of the electric motor is reduced relative to a time course, and for controlling the electric motor that reduces a torque of the electric motor at the torque reducing rate when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

a clutch engagement control step performed by the ECU for controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted during a period while the torque of the electric motor is reduced at the torque reducing rate and then engages the clutch.

8. A non-transitory computer-readable storage medium for storing a computer program causing a computer to control a vehicle driven by an internal combustion engine and an electric motor that are connected to each other through a clutch configured to connect or cut power, the vehicle comprising an Electronic Control Unit (ECU) for controlling operation of the internal combustion engine and the electric motor, to perform a process including:

an electric motor control step performed by the ECU configured to find a torque reducing rate which is determined according to a torque requested by a driver and indicates the rate at which the torque of the electric motor is reduced relative to a time course, and for controlling the electric motor that reduces a torque of the electric motor at the torque reducing rate when the clutch is engaged from a state in which the clutch is disengaged and while the vehicle is driven only by the power of the electric motor; and

a clutch engagement control step performed by the ECU for controlling the engagement of the clutch that shifts the clutch to a half-engaged clutch state where the power is partially transmitted during a period while the torque of the electric motor is reduced at the torque reducing rate and then engages the clutch.