COOLING SYSTEM FOR COOLING DRIVING MOTOR OF HYBRID VEHICLE AND METHOD FOR CONTROLLING THE SAME

• US 20120143414A1
• Filed: 06/28/2011
• Published: 06/07/2012
• Est. Priority Date: 12/02/2010
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Kim, Jong Hyun, Yi, Jaeshin, Shin, Gwang Seob, Kim, Youngchul, Lee, Jang Mi
• Granted Patent: US 8,774,996 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 11/02 with liquid cooling
• CPC Class Codes: B60K 6/20 the prime-movers consisting of electric motors and internal combustion engines, e.g. HEVs
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2510/087 Temperature

Abstract

The present invention relates to a cooling system for cooling a driving motor of a hybrid vehicle and a method for controlling the same which supplies suitable cooling flow according to temperature and temperature change rate of the driving motor. An exemplary embodiment may include: an electric oil pump to generate hydraulic pressure for cooling the driving motor; a switching valve to selectively transmit the hydraulic pressure to the driving motor; a solenoid valve to selectively supply control pressure to the switching valve so as to switch hydraulic lines in the switching valve; and a control portion controlling operations of the electric oil pump and the switching valve, wherein the control portion operates the electric oil pump by various operation amounts or stops the electric oil pump according to temperature of the driving motor and temperature change rate of the driving motor, and turns on or off the solenoid valve.

Claims

1. A cooling system for cooling a driving motor of a hybrid vehicle, comprising:

an electric oil pump to generate hydraulic pressure for cooling the driving motor of the hybrid vehicle;

a switching valve to selectively transmit the hydraulic pressure generated by the electric oil pump to the driving motor;

a solenoid valve to selectively supply control pressure to the switching valve so as to switch hydraulic lines in the switching valve; and

a control portion to control operations of the electric oil pump and the switching valve,

wherein the control portion is configured to operate the electric oil pump by first, second, and third operation amounts and stops the electric oil pump according to temperature of the driving motor and temperature change rate of the driving motor, and turns on or off the solenoid valve.

2. The cooling system of claim 1, wherein the control portion is configured to operate the electric oil pump by the first operation amount and turns on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to a first predetermined value.

3. The cooling system of claim 2, wherein the control portion is configured to operate the electric oil pump by the second operation amount and turns on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to a second predetermined value and is smaller than the first predetermined value and the temperature of the driving motor is higher than or equal to a reference temperature.

4. The cooling system of claim 3, wherein the control portion is configured to operate the electric oil pump by the third operation amount and turns on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to a third predetermined value and is smaller than the second predetermined value and the temperature of the driving motor is larger than or equal to the reference temperature.

5. The cooling system of claim 4, wherein the control portion turns off the electric oil pump and the solenoid valve in a case that the temperature change rate of the driving motor is smaller than the third predetermined value, or the temperature change rate of the driving motor is larger than or equal to the third predetermined value and is smaller than the first predetermined value and the temperature of the driving motor is lower than the reference temperature.

6. A method for controlling a cooling system which cools a driving motor of a hybrid vehicle by pumping oil by an electric oil pump and delivering the pumped oil to the driving motor by a control of a solenoid valve, the method comprising:

determining whether the driving motor operates;

detecting temperature of the driving motor in a case that the driving motor operates;

calculating temperature change rate of the driving motor based on the temperature of the driving motor;

determining whether the temperature change rate of the driving motor is larger than or equal to a first predetermined value; and

operating the electric oil pump by a first operation amount and turning on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to the first predetermined value.

7. The method of claim 6, wherein the temperature change rate of the driving motor is smaller than the first predetermined value, further comprising:

determining whether the temperature of the driving motor is higher than or equal to a reference temperature;

determining whether the temperature change rate of the driving motor is larger than or equal to a second predetermined value in a case that the temperature of the driving motor is higher than or equal to the reference temperature; and

operating the electric oil pump by a second operation amount and turning on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to the second predetermined value.

8. The method of claim 7, further comprising:

turning off the electric oil pump and the solenoid valve in a case that the temperature of the driving motor is lower than the reference temperature.

9. The method of claim 7, wherein the temperature change rate of the driving motor is smaller than the second predetermined value, further comprising:

determining whether the temperature change rate of the driving motor is larger than or equal to a third predetermined value; and

operating the electric oil pump by a third operation amount and turning on the solenoid valve in a case that the temperature change rate of the driving motor is larger than or equal to the third predetermined value.

10. The method of claim 9, further comprising:

turning off the electric oil pump and the solenoid valve in a case that the temperature change rate of the driving motor is smaller than the third predetermined value.

11. A tangible, non-transitory, computer-readable medium having instructions thereon to control a cooling system which cools a motor by pumping oil by an oil pump and delivering the pumped oil to the motor by a control of a solenoid valve, the instructions when executed by a processor operable to:

determine whether the motor operates;

detect temperature of the motor in a case that the motor operates;

calculate temperature change rate of the motor based on the temperature of the motor;

determine whether the temperature change rate of the motor is larger than or equal to a first predetermined value; and

operate the oil pump by a first operation amount and turn on the solenoid valve in response to the temperature change rate of the driving motor being larger than or equal to the first predetermined value.

12. The computer-readable medium of claim 11, wherein the temperature change rate of the motor is smaller than the first predetermined value, the instructions when executed further operable to:

determine whether the temperature of the motor is higher than or equal to a reference temperature;

determine whether the temperature change rate of the motor is larger than or equal to a second predetermined value in response to the temperature of the motor being higher than or equal to the reference temperature; and

operate the oil pump by a second operation amount and turn on the solenoid valve in response to the temperature change rate of the motor is larger than or equal to the second predetermined value.

13. The computer-readable medium of claim 12, the instructions when executed further operable to:

turn off the oil pump and the solenoid valve in response to the temperature of the motor being lower than the reference temperature.

14. The computer-readable medium of claim 13, wherein the temperature change rate of the motor is smaller than the second predetermined value, the instructions when executed further operable to:

determine whether the temperature change rate of the motor is larger than or equal to a third predetermined value; and

operate the oil pump by a third operation amount and turn on the solenoid valve in response to the temperature change rate of the motor being larger than or equal to the third predetermined value.

15. The computer-readable medium of claim 14, the instructions when executed further operable to:

turn off the oil pump and the solenoid valve in response to the temperature change rate of the motor being smaller than the third predetermined value.