Vehicle control system

• US 9,421,846 B2
• Filed: 02/25/2015
• Issued: 08/23/2016
• Est. Priority Date: 03/03/2014
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Ono, Hiroaki
• Primary Examiner(s): Kan, Yuri
• Application Number:
  US14/631,191
• Publication Number:
  US 20150246591A1
• Time in Patent Office: 545 Days
• Field of Search: 701/22, 701/102, 180/65.21, 180/65.51, 700/275, 622/592, 165/103, 603/20
• US Class Current: 1/1
• CPC Class Codes: B60H 1/004 for vehicles having a combustion engine and electric drive means, e.g. hybrid electric vehicles
• CPC Class Codes: B60H 1/143 the heat being derived from cooling an electric component, e.g. electric motors, electric circuits, fuel cells or batteries
• 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 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• 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 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2510/087 Temperature
• CPC Class Codes: B60W 2510/246 Temperature
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

When there is a demand for a heating operation of a vehicle and when there is a remaining charging capacity in a main battery, an upper limit value of a charging state of the battery is changed to a level-up upper-limit value, which higher than an ordinary upper-limit value. And an operating mode of an engine is changed to an efficiency prioritizing mode. When there is no remaining charging capacity in the main battery, the upper limit value of the charging state is changed to the ordinary upper-limit value. And the operating mode of the engine is changed to a waste-heat prioritizing mode, an engine efficiency of which is lower than that of the efficiency prioritizing mode. According to such a control, it becomes possible to warm up the engine and the battery, even in the case that there is no remaining charging capacity because of high charging state in the battery.

Claims

1. A vehicle control system for a hybrid vehicle comprising:

an engine for producing a driving force for the hybrid vehicle;

a motor-generator for generating electric power when the motor-generator is driven to rotate by the engine;

an electric-power charging device connected to the motor-generator for charging the electric power generated at the motor-generator and for supplying the electric power to an electric load of an accessory device mounted to the hybrid vehicle;

a heating system being operated by use of waste heat from the engine; and

a vehicle control device for controlling a running condition of the hybrid vehicle,

wherein the vehicle control device comprises;

a heating demand determining portion for determining whether there is a demand for a heating operation of a vehicle compartment;

a charging capacity determining portion for determining, based on a charging state of the electric-power charging device, whether there is a remaining charging capacity for the electric-power charging device;

an upper-limit value setting portion for setting an upper limit value of the charging state of the electric-power charging device depending on an existence-nonexistence of the remaining charging capacity of the electric-power charging device; and

an engine-mode setting portion for setting an operating mode of the engine,

wherein, when the heating demand determining portion determines that there is the demand for the heating operation of the vehicle compartment and when the charging capacity determining portion determines that there is the remaining charging capacity for the electric-power charging device,

(i) the upper-limit value setting portion sets the upper limit value of the charging state at a level-up upper-limit value, which is larger than an ordinary upper-limit value, and

(ii) the engine-mode setting portion changes the operating mode of the engine to an engine-efficiency prioritizing mode, and

wherein, when the heating demand determining portion determines that there is the demand for the heating operation of the vehicle compartment and when the charging capacity determining portion determines that there is no remaining charging capacity for the electric-power charging device,

(iii) the upper-limit value setting portion sets the upper limit value of the charging state at the ordinary upper-limit value, and

(iv) the engine-mode setting portion changes the operating mode of the engine to a waste-heat prioritizing mode, wherein an engine efficiency of the waste-heat prioritizing mode is lower than that of the engine-efficiency prioritizing mode.

2. The vehicle control system according to claim 1, further comprising;

a blower control portion for controlling an on-off operation of an air-conditioner blower device for blowing air into the vehicle compartment and/or an on-off operation of a battery blower device for blowing air to the electric-power charging device.

3. The vehicle control system according to claim 2, wherein

the blower control portion turns off the operation of the battery blower device, when a room temperature of the vehicle compartment is lower than a battery temperature of the electric-power charging device, and

the blower control portion turns on the operation of the battery blower device, when the room temperature of the vehicle compartment is higher than the battery temperature of the electric-power charging device.

4. The vehicle control system according to claim 2, wherein

the blower control portion turns off the operation of the air-conditioner blower device, when a cooling water temperature of engine cooling water is lower than a blower-operation threshold value, and

the blower control portion turns on the operation of the air-conditioner blower device, when the cooling water temperature is higher than the blower-operation threshold value.

5. The vehicle control system according to claim 1, wherein

the engine-mode setting portion changes the operating mode of the engine to the waste-heat prioritizing mode independently from the charging state of the electric-power charging device, when a cooling water temperature of engine cooling water is lower than a heating-operation threshold value.

6. The vehicle control system according to claim 1, wherein

the engine-mode setting portion changes the operating mode of the engine to the engine-efficiency prioritizing mode independently from the charging state of the electric-power charging device, when a cooling water temperature of engine cooling water is higher than a warm-up threshold value.

7. The vehicle control system according to claim 1, further comprising;

an estimated-time calculating portion for calculating a first estimated time period and a second estimated time period,

wherein the first estimated time period corresponds to such a period, which is necessary for a battery temperature of the electric-power charging device to reach a target battery temperature in the engine-efficiency prioritizing mode,

wherein the second estimated time period corresponds to such a period, which is necessary for the battery temperature of the electric-power charging device to reach the target battery temperature in the waste-heat prioritizing mode,

wherein the engine-mode setting portion changes the operating mode of the engine to the engine-efficiency prioritizing mode, when a time difference between the first estimated time period and the second estimated time period is smaller than a predetermined time threshold value, and

wherein the engine-mode setting portion changes the operating mode of the engine to the waste-heat prioritizing mode, when the time difference is larger than the predetermined time threshold value.

8. The vehicle control system according to claim 1, further comprising;

a fuel amount calculating portion for calculating a first fuel consuming amount and a second fuel consuming amount,

wherein the first fuel consuming amount corresponds to such a fuel amount, which is consumed by the engine until a battery temperature of the electric-power charging device reaches a target temperature value when the engine is operated in the engine-efficiency prioritizing mode,

wherein the second fuel consuming amount corresponds to such a fuel amount, which is consumed by the engine until the battery temperature reaches the target temperature value when the engine is operated in the waste-heat prioritizing mode,

wherein the engine-mode setting portion changes the operating mode of the engine to the engine-efficiency prioritizing mode, when a fuel amount difference between the first fuel consuming amount and the second fuel consuming amount is larger than a predetermined fuel amount threshold value, and

wherein the engine-mode setting portion changes the operating mode of the engine to the waste-heat prioritizing mode, when the fuel amount difference is smaller than the predetermined fuel amount threshold value.

9. The vehicle control system according to claim 1, wherein

the upper-limit value setting portion sets the upper limit value of the charging state at a first level-up upper-limit value, which is higher than an ordinary upper-limit value, when there is the remaining charging capacity for the electric-power charging device and when a room temperature of the vehicle compartment is higher than a battery temperature of the electric-power charging device, and

the upper-limit value setting portion sets the upper limit value of the charging state at a second level-up upper-limit value, which is higher than the first level-up upper-limit value, when there is the remaining charging capacity for the electric-power charging device and when the battery temperature is higher than the room temperature.