Method and system for control of a cooling system

• US 9,822,691 B2
• Filed: 04/23/2014
• Issued: 11/21/2017
• Est. Priority Date: 04/25/2013
• Status: Active Grant

• Current Assignee: Scania CV AB (Volkswagen AG)
• Original Assignee: Scania CV AB (Volkswagen AG)
• Inventors: Johansson, Svante, Jarelius, Sofie, Wikstrm, Hans, Eriksson, Rickard
• Primary Examiner(s): Tran, Long T
• Application Number:
  US14/784,347
• Publication Number:
  US 20160061093A1
• Time in Patent Office: 1,308 Days
• CPC Class Codes: F01P 11/14 Indicating devices; Other safety devices
• CPC Class Codes: F01P 2025/60 Operating parameters
• CPC Class Codes: F01P 2025/62 Load
• CPC Class Codes: F01P 2025/66 Vehicle speed
• CPC Class Codes: F01P 2037/00 Controlling
• CPC Class Codes: F01P 7/04 by varying pump speed, e.g. by changing pump-drive gear ratio
• CPC Class Codes: F01P 7/10 by throttling amount of air flowing through liquid-to-air heat exchangers
• CPC Class Codes: F01P 7/16 by thermostatic control
• CPC Class Codes: F01P 7/167 by adjusting the pre-set temperature according to engine parameters, e.g. engine load, engine speed

Abstract

A method and a system for controlling a vehicle cooling system includes: a velocity prediction unit makes a prediction of at least one future velocity profile v_pred for the vehicle; a temperature prediction unit predicts at least one future temperature profile T_pred for at least one component in the vehicle, based on at least tonnage for the vehicle; information related to a section of road ahead of the vehicle and on the at least one future velocity profile v_pred. A cooling system control unit controls the cooling system based on the at least one future temperature profile T_pred and on a limit value temperature T_{comp_lim} for the respective at least one component in the vehicle so that a number of fluctuations of an inlet temperature T_{comp_fluid_in_radiator} for the cooling fluid flow into the radiator is reduced and/or so that a magnitude of the flow into the radiator is reduced when a temperature derivative dT/dt for the inlet temperature T_{comp_fluid_in_radiator} exceeds a limit value dT/dt_lim for the temperature derivative.

Claims

1. A method for controlling a cooling system in a motor vehicle, wherein said cooling system regulates a temperature for at least one component in said vehicle and said cooling system includes a radiator connected to a thermostat controlling a flow of cooling fluid through said radiator, wherein said method comprises:

predicting at least one future velocity profile for a velocity of said vehicle along a section of road ahead of said vehicle;

predicting at least one future temperature profile for a temperature of said at least one component along said section of road, wherein said prediction of said at least one future temperature profile is based on at least a tonnage of said vehicle, on information related to said section of road, and on said at least one future velocity profile; and

said controlling said cooling system is based on said at least one future temperature profile and on a limit value temperature for said at least one component in said vehicle,

wherein if a temperature derivative for an inlet temperature for said cooling fluid in said radiator exceeds a limit value for said temperature derivative, then said controlling of said cooling system is carried out so that a reduction is achieved in at least one of

a number of fluctuations in said inlet temperature; and

a size of a flow into said radiator.

2. A method according to claim 1, wherein a cooling power of said radiator exceeds a cooling power limit value, and a cooling fluid temperature in said radiator is lower than a low cooling fluid limit value of said cooling fluid in said radiator.

3. A method according to claim 2, wherein said cooling power limit value corresponds to 100 kW, and said cooling fluid limit value corresponds to a temperature in the range from 0°

C. to −

10°

C.

4. A method according to claim 2, further comprising:

when said thermostat is closed, assigning a reference temperature indicating when said thermostat is to switch from a closed to an open state based on said future temperature profile,

wherein the assigning comprises assigning, a maximum permissible value as the reference temperature when said future temperature profile indicates that said temperature for said cooling fluid for at least one component will be lower than said limit value temperature for the respective component if limited cooling by said radiator is applied, whereby a prolonged time with a closed thermostat is obtained before said thermostat is opened.

5. A method according to claim 4, wherein, when said thermostat has opened, the assigning said reference temperature comprises assigning a minimum permissible value and using said limited cooling during the time in which said temperature for said cooling fluid is decreasing toward said minimum permissible value, resulting in a prolonged time with said thermostat open is obtained before said thermostat is closed.

6. A method according to claim 5, wherein said prolonged time with said thermostat closed and said prolonged time with said thermostat open collectively result in a prolonged period of time between two consecutive openings of said thermostat.

7. A method according to claim 5, wherein said maximum permissible value corresponds to about 105°

C. and said minimum permissible value corresponds to about 70°

C.

8. A method according to claim 4, wherein said limited cooling is defined by at least one of the group consisting of:

a flow of less than 5 liters per minute through said radiator;

a passive airflow through said radiator; and

actively controlling said limited cooling so that a cooling fluid temperature is controlled toward a predefined relatively low reference temperature.

9. A method according to claim 1, further comprising:

preheating said cooling fluid when a predicted inflow Q into said radiator, which is determined based on said future temperature profile exceeds an inflow limit value, and when a cooling power for said radiator exceeds a cooling power limit value, and a cooling fluid temperature in said radiator is lower than a low cooling fluid limit value for said cooling fluid in said radiator.

10. A method according to claim 9, wherein said preheating is achieved by gradually increasing the size of the flow into said radiator, whereby said cooling fluid temperature is increased.

11. A method according to claim 10, further comprising:

when performing said gradual increasing of said flow Q into said radiator, taking at least one measure of the group consisting of;

closing of a radiator blind; and

controlling the cooling fluid flow into said radiator by an adjustable cooling water pump.

12. A method according to claim 9, further comprising when said preheating of said cooling fluid is performed, applying limited cooling by said radiator if a temperature derivative for a temperature for said cooling fluid for said at least one component is predicted to exceed a limit value for the temperature derivative.

13. A method according to claim 12, wherein said limited cooling comprises limiting an opening of said thermostat so that said future temperature profile indicates that, for every said at least one component, said future temperature profile is lower than said limit value temperature for the respective component.

14. A method according to claim 13, wherein said limiting of said opening results in said thermostat being closed.

15. method according to claim 1, further comprising arranging pre-cooling of said cooling fluid if said future temperature profile indicates that a temperature derivative for an actual temperature for any of said at least one components is greater than a high limit value for the temperature derivative when a cooling fluid temperature in said radiator is higher than a high cooling fluid limit value for said cooling fluid in said radiator.

16. A method according to claim 15, wherein said high cooling fluid limit value for said cooling fluid corresponds to about 60°

C.

17. A method according to claim 15, wherein said pre-cooling is achieved by opening of said thermostat followed by passive cooling of said cooling fluid.

18. A method according to claim 15, wherein said pre-cooling continues until at least one occurrence in the group consisting of:

said cooling fluid temperature reaches a temperature limit value;

said cooling fluid temperature reaches said limit value temperature for said cooling fluid; and

said future temperature profile indicates that a temperature for any of said at least one components does not exceed said limit value temperature.

19. A method according to claim 15, further comprising:

determining said future temperature profile based on said temperature derivative for said temperature for said cooling fluid exceeding a high limit value for said temperature derivative,

wherein limited cooling by said radiator is applied after said pre-cooling of said cooling fluid.

20. A method according to claim 15, wherein said limited cooling is obtained when said temperature derivative for said temperature for said cooling fluid exceeds a high limit value for the temperature derivative, wherein an opening of said thermostat is limited so that said future temperature profile indicates that a temperature for said at least one component is lower than said limit value temperature for said at least one component.

21. A method according to claim 20, wherein said limitation of said opening results in said thermostat being closed.

22. A method according to claim 1, further comprising causing the inlet temperature at an inlet end of a container of said radiator to be essentially constant if a cooling fluid temperature in said radiator is higher than a high cooling fluid limit value for said cooling fluid in said radiator, and if said future temperature profile indicates a future temperature imbalance in said cooling system,

wherein the inlet temperature at the inlet end of the container is essentially constant when the inlet temperature is at or is approaching equilibrium with a second temperature at a second end of the container of the radiator, the second end being distal to the inlet end.

23. A method according to claim 22, wherein said high cooling fluid limit value has a value corresponding to about 90°

C.

24. A method according to claim 22, further comprising achieving said essentially constant inlet temperature by pre-controlling said cooling system to meet a predicted cooling demand, wherein said predicted cooling demand is determined based on said future temperature profile,

wherein the inlet temperature at the inlet end of the container is essentially constant when the inlet temperature is at or is approaching equilibrium with a second temperature at a second end of the container of the radiator, the second end being distal to the inlet end.

25. A method according to claim 1, wherein said at least one component comprises at least one of the group consisting of:

said cooling fluid;

a motor oil;

a retarder device;

a cylinder material in an engine;

an exhaust recirculation device;

a turbocharger;

a dual turbocharger;

a transmission;

a compressor for a brake system;

exhaust from an engine;

a post-processing device for exhaust; and

an air-conditioning system.

26. A method according to claim 1, wherein said information related to said section of road includes a road gradient.

27. A method according to claim 26, wherein said information relating to said section of road includes said road gradient that is determined based on information selected from the group consisting of:

radar-based information;

camera-based information;

information obtained from a vehicle other than said vehicle;

road gradient information and positioning information previously stored in said vehicle; and

information obtained from a traffic system related to said section of road.

28. A method according to claim 1, wherein said information related to said section of road includes at least one selected from the group consisting of:

a driving resistance acting upon said vehicle;

a speed limit for said section of road;

a velocity history for said section of road; and

traffic information.

29. A method according to claim 1, wherein said prediction of said at least one future temperature profile is also based on at least one from the group consisting of:

a predicted torque delivered by said engine;

an rpm for said engine;

a gear selection for a transmission in said vehicle;

a component use in said vehicle;

an airflow through said radiator;

an ambient air pressure; and

an ambient temperature.

30. A system arranged for controlling a cooling system in a motor vehicle, wherein said cooling system is configured to regulate a temperature for at least one component in said vehicle, and said cooling system comprises a radiator connected to a thermostat controlling a flow of cooling fluid through said radiator, said system comprising:

a velocity prediction unit configured to predict at least one future velocity profile for a velocity of said vehicle over a section of road ahead of said vehicle;

a temperature prediction unit, configured to predict at least one future temperature profile for a temperature for said at least one component over said section of road, wherein said prediction of the at least one future temperature profile is based on at least a tonnage for said vehicle, on information related to said section of road and on said at least one future velocity profile; and

a cooling system controller configured and operable to control said cooling system based on said at least one future temperature profile and on a limit value temperature of said at least one component in said vehicle,

wherein, if a temperature derivative for an inlet temperature for said cooling fluid into said radiator exceeds a limit value for said temperature derivative, said cooling system controller is configured to control said cooling system to achieve a reduction of at least one of;

a number of fluctuations in an inlet temperature for said cooling fluid into said radiator; and

a magnitude of a flow into said radiator.

31. A cooling system in a motor vehicle, and a control system configured to control the cooling system and comprising a non-transitory computer-readable medium incorporating a computer program, said control system comprising:

a velocity predictor configured to predict a future velocity profile for a velocity of the motor vehicle over a section of road ahead of the motor vehicle;

a temperature predictor configured to predict a future temperature profile for a temperature for a component over the section of road, wherein the prediction of the future temperature profile is based on at least a tonnage for the motor vehicle, on information related to the section of road, and the future velocity profile;

said cooling system comprising a radiator connected to a thermostat controlling a flow of cooling fluid through said radiator, and said cooling system is configured to regulate the temperature of said component of the motor vehicle; and

said control system configured to control said cooling system based on a the future temperature profile and on a limit value temperature of the component in the motor vehicle;

wherein, when a temperature derivative for an inlet temperature for the cooling fluid into said radiator exceeds the limit value for the temperature derivative, said control system is configured to control said cooling system to achieve a reduction of at least one of;

a number of fluctuations in the inlet temperature for the cooling fluid into said radiator; and

a magnitude of a flow into said radiator.