KR20170065387A - Apparatus and method for control of engine cooling system - Google Patents

Apparatus and method for control of engine cooling system Download PDF

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Publication number
KR20170065387A
KR20170065387A KR1020150171761A KR20150171761A KR20170065387A KR 20170065387 A KR20170065387 A KR 20170065387A KR 1020150171761 A KR1020150171761 A KR 1020150171761A KR 20150171761 A KR20150171761 A KR 20150171761A KR 20170065387 A KR20170065387 A KR 20170065387A
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South Korea
Prior art keywords
engine
load state
future
altitude information
current
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KR1020150171761A
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Korean (ko)
Inventor
정일
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현대자동차주식회사
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Priority to KR1020150171761A priority Critical patent/KR20170065387A/en
Publication of KR20170065387A publication Critical patent/KR20170065387A/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/02—Controlling of coolant flow the coolant being cooling-air
    • F01P7/10—Controlling of coolant flow the coolant being cooling-air by throttling amount of air flowing through liquid-to-air heat exchangers
    • F01P7/12—Controlling of coolant flow the coolant being cooling-air by throttling amount of air flowing through liquid-to-air heat exchangers by thermostatic control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/02—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to ambient conditions
    • B60W40/06—Road conditions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/02—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to ambient conditions
    • B60W40/06—Road conditions
    • B60W40/076—Slope angle of the road
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
    • F01P2007/168—By varying the cooling capacity of a liquid-to-air heat-exchanger
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2025/00—Measuring
    • F01P2025/60—Operating parameters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2025/00—Measuring
    • F01P2025/60—Operating parameters
    • F01P2025/66—Vehicle speed

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • General Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical & Material Sciences (AREA)
  • Mathematical Physics (AREA)
  • Transportation (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)

Abstract

An apparatus for controlling a cooling system of an engine according to an embodiment of the present invention includes an altitude information storage unit for storing altitude information, a cooling fan that selectively blows air to the radiator through the electronic fan clutch, And a control unit for predicting a future load state of the engine according to a current load state of the received engine and controlling the operation of the cooling fan according to a future load state of the engine.
Accordingly, the temperature of the cooling water, through which the cooling fan is operated, can be variably controlled after a predetermined time of the engine in accordance with the load, thereby minimizing the energy discharged to the outside through the cooling water, thereby reducing fuel consumption.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cooling system control apparatus,

The present invention relates to an engine cooling system control apparatus and a control method thereof, and more particularly, to an engine cooling system control apparatus and control method thereof that variably control the operation of a cooling fan of an engine cooling system mounted on a vehicle.

The thermostat for automobile is installed between the engine and the radiator. It automatically opens and closes according to the temperature change of the cooling water, and keeps the cooling water in the set temperature range by controlling the flow rate to the radiator.

In the mechanical thermostat, the wax expands according to the temperature of the cooling water, and the piston causes the opening and closing displacement of the valve by the expansion force.

Such a mechanical thermostat operates in accordance with an opening / closing temperature set at a predetermined temperature, and simply opens and closes the valve at a predetermined temperature, and thus can not actively cope with changes in the driving environment and conditions of the vehicle.

An electronic thermostat has been proposed to compensate for the disadvantages of the mechanical thermostat and to keep the cooling water temperature of the engine at an optimal state.

Such an electronic thermostat can maintain the optimum cooling water temperature by actively controlling the cooling water temperature of the engine according to the traveling environment such as the load condition of the vehicle and can improve the fuel efficiency and reduce the exhaust gas compared with the mechanical thermostat have.

A temperature sensitive and electronically actuated drive unit is applied to open and close the valve of the thermostat. Such a drive unit includes a wax, a semi-fluid, a rubber piston, a backup plate, and a main piston.

On the other hand, the temperature of the cooling water in which the thermostat and the cooling fan are operated is fixed, and operation is performed irrespective of the load of the engine and the temperature of the outside air, thereby wasting energy through the cooling water.

An object of the present invention is to provide an apparatus and method for controlling a cooling system of an engine capable of reducing the energy wasted to the outside through cooling water by varying the temperature of the cooling water in which the cooling fan is operated, .

An apparatus for controlling an engine cooling system according to an embodiment of the present invention includes: an altitude information storage unit for storing altitude information; A cooling fan that blows air into the radiator but is selectively activated through an electronic fan clutch; And a control unit for predicting the future load state of the engine according to the altitude information and the current load state of the engine received from the engine and controlling the operation of the cooling fan according to the future load state of the engine.

The control unit may variably control the temperature of the cooling water in which the cooling fan is operated according to the future load state of the engine.

The altitude information may be altitude information of the current position and altitude information of the future position predicted according to the speed of the current vehicle.

 The controller calculates the current road gradient information and the future road gradient information using the altitude information of the current position and the altitude information of the future position, and predicts the future load state of the engine by using the information.

The control unit estimates the future load state of the engine at a high load in the case of an uphill section by using the altitude information of the current position and the altitude information of the future position, .

The controller may control the temperature of the cooling water to be operated by the cooling fan to be lower through the electromagnetic fan clutch as the future load state of the engine increases.

The controller may control the temperature of the cooling water to be operated by the cooling fan to be higher through the electronic fan clutch as the future load state of the engine is lowered.

The controller may variably control the temperature of the cooling water operated by the cooling fan using the current load state of the engine received from the engine and the predicted future load state of the engine.

The control unit may variably control the temperature of the cooling water according to a high value of a current load state of the engine and a future load state of the engine.

The cooling system control apparatus for an engine according to an embodiment of the present invention may further include a thermostat disposed in a cooling water line that selectively supplies cooling water to the radiator.

A method for controlling a cooling system of an engine according to an embodiment of the present invention includes the steps of: storing the current load state of the engine, altitude information of the current position, and altitude information of a future position predicted according to the current speed of the vehicle, Calculating a future load state of the engine using the state information, the altitude information of the current position, and the altitude information of the future position, and generating a control signal of the electronic fan clutch using the calculated future load state of the engine And variably controlling the operation of the cooling fan using the generated control signal.

The step of calculating the future load state of the engine may further include calculating the current road gradient and the future road gradient information using the altitude information of the current position and the altitude information of the future position.

Wherein the step of variably controlling the operation of the cooling fan includes calculating a cooling water target temperature corresponding to a future load state of the engine; And calculating a target cooling fan rotation speed corresponding to the calculated cooling water target temperature information.

An apparatus and method for controlling a cooling system of an engine according to an embodiment of the present invention minimize the energy released to the outside through cooling water by variably controlling the temperature of the cooling water operated by the cooling fan in accordance with the load state after a predetermined time of the engine Thereby reducing fuel consumption.

1 is a schematic block diagram of an apparatus for controlling a cooling system of an engine according to an embodiment of the present invention.
2 is a flowchart showing the operation of the engine cooling system control method according to the embodiment of the present invention.
3 is a table showing a method of controlling cooling water temperature and cooling fan rotation in an engine cooling system control apparatus according to an embodiment of the present invention.
4 is a schematic block diagram of an electronic fan clutch in an engine cooling system control apparatus according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The components are described and explained in order to facilitate understanding of the patent, and other components not shown in the drawings refer to well-known technologies well known to those skilled in the art, and a description thereof will be omitted.

1 is a schematic block diagram of an apparatus for controlling a cooling system of an engine according to an embodiment of the present invention.

1, an engine cooling system control apparatus includes an engine 110, an altitude information storage unit 120, an electronic fan clutch 130, an electronic thermostat 140, a coolant temperature sensor 150, a speed sensor 160, a cooling fan 170, a radiator 180, and a control unit 100.

The engine 110 and the electronic thermostat 140 are circulated when the temperature of the cooling water is low and the engine 110 and the electronic thermostat 140 are connected to each other when the temperature of the cooling water is high in the embodiment of the present invention. (170) to control the temperature of the cooling water.

When the electronic thermostat 140 is operated so that the cooling water circulates through the radiator 170, the cooling fan 160 operates through the electronic fan clutch 130. Here, the electromagnetic fan clutch 130 transmits the rotational force of the motor or the engine to the cooling fan 160.

The engine 110 may transmit information indicating the load state to the control unit 100 using the operating condition of the engine 110 under the control of the control unit 100. [ The load status information can be generated from the operating conditions of the engine 110, such as the number of revolutions of the engine 110, the fuel injection amount information of the engine 110, and the like.

The altitude information storage unit 120 may store the altitude information according to the location information and may transmit the altitude information according to the current location of the vehicle to the control unit 100. The altitude information storage unit 120 may be a part of the navigation device and may further include a current position detector (not shown) for detecting information about the current position of the vehicle. At this time, the current position detection unit may determine the coordinate data corresponding to the current position of the vehicle based on, for example, a radio wave transmitted from the GPS satellite, and detect the current position of the vehicle by matching the coordinate data with the map data .

 However, in the embodiment of the present invention, the altitude information storage unit 120 stores information on any device capable of providing information on the shape of the road such as the gradient of the road or the radius of curvature (for example, ≪ / RTI > including servers storing data) may also be included.

At this time, the altitude information storage unit 120 is connected to the speed sensor 160. The speed sensor 160 may measure the speed of the current vehicle and transmit it to the altitude information storage unit 120. The altitude information storage unit 120 may transmit the altitude information (hereinafter, referred to as " altitude information of the future location ") according to the position of the vehicle, which is expected to be located after a predetermined time in accordance with the current vehicle speed information, have.

The control unit 100 receives the altitude information from the altitude information storage unit 120 and the current load status information of the engine 110 from the engine 110. The control unit 100 calculates the current road gradient and the future road gradient according to the received altitude information of the current position and the altitude information of the future position and calculates a load state after a predetermined time using the calculated road gradient and the load state information of the engine (Hereinafter referred to as " future load state ").

In the present embodiment, the future load state B of the engine can be defined as Equation 1 according to the current road gradient state.

Figure pat00001

A is the current load state of the engine, C is the current road gradient, and D is the future road gradient.

That is, when it is determined that the vehicle is in an uphill section according to the current road gradient and the future road gradient, the future load state of the engine is obtained as a high load state higher than the current load state of the engine. Further, when it is determined that the engine is in the downhill section, the future load state of the engine can be obtained in a low load state that is lower than the current load state of the engine.

The control unit 100 may calculate the cooling water target temperature corresponding to the future load state of the engine using the calculated future load state of the engine. Or calculate the cooling water target temperature corresponding to the calculated future load state of the engine and the current load state of the engine received from the engine 110, whichever is greater.

The control unit 100 may include a storage unit (not shown) having a cooling water temperature variable control map in which a corresponding cooling fan target temperature is stored in advance according to the load state of the engine. The variable coolant temperature control map can be configured so that the coolant target temperature becomes higher as the load condition of the engine is lower.

The control unit 100 generates a control signal for the electronic fan clutch 130 according to the computed future load state of the engine and controls the operation of the electronic fan clutch 130 according to the generated control signal for the electronic fan clutch 130 . The control unit 100 may control the operation of the cooling fan 170 through the electronic fan clutch 130 operated according to the control signal of the electronic fan clutch 130. [ That is, the control unit 100 predicts the future load state of the engine and controls the cooling fan 170 to operate in a variable manner, thereby varying the temperature of the cooling water.

2 is a flowchart showing the operation of the engine cooling system control method according to the embodiment of the present invention. 2, the control unit 100 of the engine cooling system control apparatus determines the current load state of the engine from the engine 110, the altitude information and the future altitude information according to the current position of the vehicle from the altitude information storage unit 120 (S210).

The control unit 100 calculates the future load state of the engine using the stored current state of the engine and the altitude information and the future altitude information according to the current position (S220).

The controller 100 calculates the current road gradient and the future road gradient according to the received current altitude information and the future altitude information, and calculates the future road load of the engine using the calculated road gradient and the current load state information of the engine The state can be obtained.

At this time, when it is determined that the vehicle is in an uphill section according to the current road gradient and the gradient of the future road, the future load state of the engine can be obtained with a higher load state than the current load state of the engine. Further, when it is determined that the engine is in the downhill section, the future load state of the engine can be obtained in a low load state that is lower than the current load state of the engine.

Thereafter, the controller 100 generates a control signal for the electronic fan clutch using the calculated future load state of the engine, and can variably control the operation of the cooling fan using the generated control signal (S230).

More specifically, the control unit 100 can calculate the cooling water target temperature corresponding to the future load state of the engine through the cooling water temperature variable control map.

Next, the control unit 100 can calculate the target number of rotations of the cooling fan 170 corresponding to the calculated target temperature of the cooling water through the number of rotations of the cooling fan.

Thereafter, the control unit 100 generates a control signal for the electronic fan clutch 130 from the computed cooling fan target revolution speed information, and controls the operation of the cooling fan 170 through the generated control signal for the electronic fan clutch 130 can do.

3 is a table showing a method of controlling cooling water temperature and cooling fan rotation in an engine cooling system control apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the logic for controlling the electronic fan clutch 130 includes a cooling water temperature control part and a cooling fan rotation speed control part.

In the cooling water temperature control part, the cooling fan operation temperature is regarded as the cooling water target temperature, and the cooling fan target rotation speed is calculated by the PI control method for the difference between the cooling water target temperature and the actual cooling water temperature difference.

In the cooling fan speed control part, the PWM signal is adjusted by the PI control method for the difference between the target rotational speed of the cooling fan and the actual rotational speed of the cooling fan to integrate the cooling fan rotational speed with the cooling fan target rotational speed.

4 is a schematic block diagram of an electronic fan clutch in an engine cooling system control apparatus according to an embodiment of the present invention.

Referring to FIG. 4, the control unit 100 generates a control signal, and the electromagnetic fan clutch 130 operates the oil valve in accordance with the control signal to supply oil from the oil storage chamber to the operation chamber.

The electromagnetic fan clutch 130 is operated by the oil supplied to the operating chamber to transmit the rotational force of the motor to the cooling fan 170.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And all changes to the scope that are deemed to be valid.

100: control unit 110: engine
120: altitude information storage unit 130: electronic fan clutch
140: Electronic thermostat 150: Coolant temperature sensor
160: speed sensor 170: cooling fan
180: Radiator

Claims (13)

An altitude information storage unit for storing altitude information;
A cooling fan that blows air into the radiator but is selectively activated through an electronic fan clutch; And
A controller for predicting a future load state of the engine in accordance with the altitude information and the current load state of the engine received from the engine and controlling the operation of the cooling fan according to the future load state of the engine,
And a cooling system control unit for controlling the cooling system of the engine. The method of claim 1,
Wherein,
Wherein the controller controls the temperature of the cooling water in which the cooling fan is operated according to a future load state of the engine. 3. The method of claim 2,
Wherein the altitude information comprises:
The altitude information of the current position, and the altitude information of the future position predicted according to the present speed and current position of the vehicle. 4. The method of claim 3,
Wherein,
Calculating current road gradient information and future road gradient information by using the altitude information of the current position and the altitude information of the future position, and predicting a future load state of the engine by using the information. 5. The method of claim 4,
Wherein,
An engine for predicting a future load state of the engine at a high load and an engine for predicting a future load state of the engine at a low load in the case of a downhill section in the case of an uphill section using the altitude information of the current position and the altitude information of the future position Cooling system control device. The method of claim 5,
Wherein,
And controls the temperature of the cooling water in which the cooling fan is operated to be lower as the future load of the engine increases. The method of claim 5,
Wherein,
And controls the temperature of the cooling water in which the cooling fan is operated to be higher as the future load of the engine is lowered. The method of claim 5,
Wherein,
Wherein the control unit variably controls the temperature of the cooling water operated by the cooling fan by using the current load state of the engine received from the engine and the predicted future load state of the engine. 9. The method of claim 8,
Wherein,
Wherein the temperature of the cooling water is variably controlled according to a high value among a current load state of the engine and a future load state of the engine. The method of claim 1,
Further comprising a thermostat disposed in a cooling water line that selectively supplies cooling water to the radiator. Storing altitude information of the present load state of the engine, altitude information of the current position, and future position predicted according to the current speed and current position of the vehicle;
Calculating a future load state of the engine using the current load state of the engine, the altitude information of the current position, and the altitude information of the future position; And
Generating a control signal of the electronic fan clutch using the calculated future load state of the engine, and variably controlling the operation of the cooling fan by using the generated control signal
And the engine cooling system control method. 12. The method of claim 11,
Wherein calculating the future load state of the engine comprises:
Calculating current road gradient and future road gradient information using the altitude information of the current location and the altitude information of the future location. 12. The method of claim 11,
The step of variably controlling the operation of the cooling fan includes:
Calculating a cooling water target temperature corresponding to a future load state of the engine; And
Calculating a target cooling fan rotation speed corresponding to the calculated cooling water target temperature information
Further comprising the steps of:
KR1020150171761A 2015-12-03 2015-12-03 Apparatus and method for control of engine cooling system KR20170065387A (en)

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