Control device for hybrid vehicle, and hybrid vehicle incorporating control device

• US 8,781,665 B2
• Filed: 04/07/2010
• Issued: 07/15/2014
• Est. Priority Date: 04/07/2010
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yamamoto, Masaya, Endo, Hiroki, Tsukayama, Masaru
• Primary Examiner(s): Algahaim, Helal A
• Assistant Examiner(s): PATEL, SHARDUL D
• Application Number:
  US13/639,485
• Publication Number:
  US 20130030633A1
• Time in Patent Office: 1,560 Days
• Field of Search: 701/22, 180/65.23, 180/65.265, 903/930, 318/432
• US Class Current: 701/22
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• 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 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2710/086 Power
• CPC Class Codes: B60W 50/082 Selecting or switching between different modes of propelling
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

An ECU uses a map or the like prepared in advance to calculate a discharge allowable power. Then, the ECU sets a VH upper limit value at the first upper limit value. When the running mode is not at a CD mode (that is, at a CS mode), or when the engine is operating, the ECU proceeds to S60. In contrast, when the running mode is at the CD mode and the engine is stopped, the ECU increases the discharge allowable power, and modifies the VH upper limit value to a second upper limit value that is lower than the first upper limit value.

Claims

1. A control device for a hybrid vehicle,

said hybrid vehicle including

an internal combustion engine and an electric motor generating a vehicle driving force,

a power storage device capable of being charged and discharged,

a drive device driving said electric motor, and

a voltage converter provided between said driving device and said power storage device, configured to allow boosting of an input voltage of said driving device to a level higher than a voltage of said power storage device,

said control device comprising:

a running mode control unit controlling switching of a running mode including a first mode in which said internal combustion engine is stopped and running using said electric motor alone is given priority, and a second mode in which said internal combustion engine is operated and a state of charge indicating a charging state of said power storage device is maintained at a predetermined target; and

a voltage upper limit control unit modifying a voltage upper limit value indicating an upper limit of voltage boosted by said voltage converter based on said running mode and operation/stop of said internal combustion engine, wherein

said voltage upper limit control unit takes a first upper limit value as said voltage upper limit value when said running mode is at said first mode and said internal combustion engine is operating, or when said running mode is at said second mode, and takes a second upper limit value lower than said first upper limit value as said voltage upper limit value when said running mode is at said first mode and said internal combustion engine is stopped;

said control device further comprising;

a discharge allowable power control unit increasing, when said running mode is at said first mode and said internal combustion engine is stopped, a discharge allowable power indicating electric power that can be discharged from said power storage device than when said running mode is at said first mode and said internal combustion engine is operating, or than when said running mode is at said second mode.

2. The control device for a hybrid vehicle according to claim 1,

said hybrid vehicle further including a charging device configured to receive supply of electric power from a power supply external to the vehicle to charge said power storage device,

wherein said running mode control unit sets said running mode at said first mode after said power storage device is charged by said charging device.

3. A hybrid vehicle including a control device defined in claim 1.

4. A hybrid vehicle including a control device defined in claim 2.

5. A control device for a hybrid vehicle,

said hybrid vehicle including

an internal combustion engine and an electric motor generating a vehicle driving force,

a power storage device capable of being charged and discharged,

a drive device driving said electric motor, and

a voltage converter provided between said driving device and said power storage device, configured to allow boosting of an input voltage of said driving device to a level higher than a voltage of said power storage device,

said control device comprising:

a running mode control unit controlling switching of a running mode including a first mode in which said internal combustion engine is stopped and running using said electric motor alone is given priority, and a second mode in which said internal combustion engine is operated and a state of charge indicating a charging state of said power storage device is maintained at a predetermined target; and

a voltage upper limit control unit modifying a voltage upper limit value indicating an upper limit of voltage boosted by said voltage converter based on said running mode and operation/stop of said internal combustion engine, wherein

said voltage upper limit control unit takes a first upper limit value as said voltage upper limit value when said running mode is at said first mode and said internal combustion engine is operating, or when said running mode is at said second mode, and takes a second upper limit value lower than said first upper limit value as said voltage upper limit value when said running mode is at said first mode and said internal combustion engine is stopped;

said control device further comprising;

a torque requirement calculation unit calculating a torque upper limit value indicating an upper limit value of torque output from said electric motor; and

a determination unit carrying out a determination of starting said internal combustion engine based on a comparison result between required torque of said hybrid vehicle and said torque upper limit value; and

wherein, when said voltage upper limit value is said second upper limit value, said torque requirement calculation unit takes, as said torque upper limit value, a smaller of torque that is a subtraction of reaction force generated at said electric motor at a time of starting said internal combustion engine from torque of said electric motor when the voltage boosted by said voltage converter is said first upper limit value, and the torque of said electric motor when the voltage boosted by said voltage converter is said second upper limit value.

6. A hybrid vehicle including a control device defined in claim 5.