Control device for vehicle

Abstract

To provide a control device capable of reducing electric power consumption of a vehicle and reducing noise of a radiator fan by reducing air quantity of the radiator fan during rainfall.SOLUTION: An ECU 20 controls air quantity of a radiator fan 17 of a vehicle 10 that includes: a cooling water circuit 15 for circulating cooling water; a radiator 16 for radiating heat from the cooling water; and the radiator fan 17 for blowing air toward the radiator 16. The air quantity of the radiator fan 17 is calculated on the basis of a temperature of the cooling water and speed of the vehicle 10. Meteorological information is acquired and when rainfall is determined from the meteorological information, the calculated air quantity of the radiator fan 17 is reduced.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control device for controlling the airflow rate of a radiator fan of a vehicle. [Background technology]

[0002] A radiator fan is a fan that blows air toward a radiator. The radiator is a heat exchanger that dissipates heat from coolant. The coolant cools, for example, a motor and a PCU (Power Control Unit) of a hybrid vehicle. For example, Patent Document 1 discloses a control device that controls the airflow of a vehicle's radiator fan based on the coolant temperature and vehicle speed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-154958 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when it rains, water droplets adhere to the radiator and evaporate, absorbing latent heat from the radiator, increasing the radiator's heat dissipation capacity. In this case, if the airflow rate of the radiator fan is controlled based only on the coolant temperature and vehicle speed, the airflow rate of the radiator fan may be greater than necessary.

[0005] Therefore, an object of the present invention is to provide a control device that can reduce the power consumption of a vehicle and the noise level of the radiator fan by reducing the airflow rate of the radiator fan when it is raining. [Means for solving the problem]

[0006] The vehicle control device of the present invention is a control device that controls the airflow of the radiator fan of a vehicle that is equipped with a coolant circuit that circulates coolant, a radiator that dissipates heat from the coolant, and a radiator fan that blows air toward the radiator, and is characterized in that it calculates the airflow of the radiator fan based on the temperature of the coolant and the vehicle speed, acquires weather information, and if it determines from the weather information that rain is expected, reduces the calculated airflow of the radiator fan. [Effects of the Invention]

[0007] According to the control device of the present invention, by reducing the airflow rate of the radiator fan when it is raining, it is possible to reduce the power consumption of the vehicle and reduce the noise of the radiator fan. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing a vehicle according to an embodiment; [Figure 2] 1 is a block diagram showing a configuration of a control device (ECU) according to an embodiment; [Figure 3] FIG. 4 is a flowchart illustrating a flow of radiator fan air volume control according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] An example of an embodiment of the present invention will be described in detail below. In the following description, specific shapes, materials, directions, numerical values, etc. are examples for facilitating understanding of the present invention, and can be appropriately changed according to the application, purpose, specifications, etc.

[0010] [vehicle] A vehicle 10 according to an embodiment will be described with reference to FIG.

[0011] Vehicle 10 is a hybrid vehicle and has two power sources, an engine 11 and a motor 12, each of which will be described in detail below, a PCU (Power Control Unit) 13 that controls motor 12, a battery 14 that supplies power to motor 12, a coolant circuit 15 that circulates coolant to cool motor 12 and PCU 13, a radiator 16 provided in coolant circuit 15 to dissipate heat from the coolant, a radiator fan 17 that blows air toward radiator 16, a coolant temperature sensor 18 that detects the temperature of the coolant, a vehicle speed sensor 19 that detects the speed of vehicle 10, and an ECU (Electronic Control Unit) 20 as a control device that controls the air volume of radiator fan 17.

[0012] The vehicle of the present invention is not limited to a hybrid vehicle, but may be an electric vehicle powered by a motor, an engine vehicle powered by an engine, or the like.

[0013] The engine 11 is a water-cooled engine and is cooled by engine coolant. The engine coolant circulates through an engine coolant circuit that passes through a water jacket formed in the engine 11. The engine coolant circuit may be provided with a radiator that dissipates heat from the engine coolant.

[0014] As described above, the motor 12 is driven by the power of the battery 14. The motor 12 also functions as a generator and can charge the battery 14 with power when the engine 11 is driven. The motor 12 is cooled by the cooling water circulating through the cooling water circuit 15.

[0015] As described above, the PCU 13 controls the motor 12. The PCU 13 includes a boost converter, an inverter that drives or regenerates the motor 12, an intelligent power module, and the like. The PCU 13 converts the voltage supplied from the battery 14 into a voltage for driving the motor 12, converts the power generated by the motor 12 (generator) into a DC current for charging the battery 14, and efficiently regenerates power by having the motor 12 (generator) generate power during deceleration. The PCU 13 is cooled by cooling water circulating through a cooling water circuit 15.

[0016] As described above, the battery 14 supplies power to the motor 12, the radiator fan 17, etc. The battery 14 is preferably a lithium ion battery or the like.

[0017] As described above, the coolant circuit 15 circulates the coolant that cools the motor 12 and the PCU 13. As described above, the coolant circuit 15 is provided with the radiator 16 that dissipates heat from the coolant. The coolant circuit 15 may also be provided with a reservoir tank, a water pump for circulating the coolant, and the like.

[0018] The radiator 16 is a heat exchanger that allows coolant to flow inside and releases heat to the surrounding air by thermal conduction. The radiator 16 has a core made of an array of many finned thin tubes made of, for example, an aluminum alloy, and a tank that connects the inlets and outlets of the thin tubes. The core may be of a downflow (vertical flow) type or a crossflow (horizontal flow) type, depending on the flow direction. The above-mentioned radiator fan 17 that blows air toward the radiator 16 is provided near the radiator 16. The radiator 16 is cooled by the air blown by the radiator fan 17.

[0019] The radiator of the present invention may be a radiator that dissipates heat from the cooling water that cools the battery 14 or a radiator that dissipates heat from the cooling water that cools the engine 11.

[0020] As described above, the radiator fan 17 sends air toward the radiator 16. The radiator fan 17 is driven by a fan motor (not shown). The fan motor is driven by power from the battery 14. The air volume of the radiator fan 17 is changed by changing the rotation speed of the fan motor. The rotation speed of the fan motor is changed by the ECU 20 changing the duty ratio of a PWM (Pulse Width Modulation) signal.

[0021] The airflow rate of the radiator fan 17 may be set to one of a number of modes, which are obtained by dividing the rotation speed of the fan motor into stages, such as OFF, LO, MID, HIGH, etc., in order of decreasing airflow rate. In the OFF mode, the radiator fan 17 is stopped.

[0022] As described above, the coolant temperature sensor 18 detects the temperature of the coolant circulating through the coolant circuit 15. The coolant temperature sensor 18 is provided at the outlet of the radiator 16 in the coolant circuit 15. The coolant temperature sensor 18 is connected to the ECU 20.

[0023] As described above, the vehicle speed sensor 19 detects the speed of the vehicle 10. The vehicle speed sensor 19 may detect the speed of the vehicle 10, for example, by detecting the rotation speed of the drive wheels of the vehicle 10. The vehicle speed sensor 19 is connected to the ECU 20.

[0024] [Control device] An ECU 20 as a control device according to an embodiment will be described with reference to FIGS. 1 and 2. FIG.

[0025] 1, as described above, ECU 20 controls the airflow rate of radiator fan 17. As will be described in detail later, ECU 20 reduces the airflow rate of radiator fan 17 during rainfall, thereby reducing the power consumption of vehicle 10 and the noise level of radiator fan 17.

[0026] 2, the ECU 20 is a computer including a CPU 21 as a processor, a memory 22, an in-vehicle communication interface 23, and a wireless communication interface 24. The CPU 21, the memory 22, the in-vehicle communication interface 23, and the wireless communication interface 24 are connected via an internal bus 25.

[0027] The CPU 21 is a processor that processes information. The memory 22 stores a control program 26 and control program data 27 for executing the control program 26. The CPU 21 executes the control program 26 stored in the memory 22 to realize various control operations.

[0028] The in-vehicle communication interface 23 is connected to an in-vehicle bus 28 of the vehicle 10, and is connected to other ECUs of the vehicle 10 via the in-vehicle bus 28 using the CAN protocol.

[0029] The wireless communication interface 24 is a wireless communication module connected to a network for communicating with an external server (not shown). The ECU 20 acquires weather information from the external server via the network. The weather information includes whether or not it will rain, the probability of precipitation, etc. The external server may be provided in a meteorological agency. The wireless communication interface 24 may also be provided in an in-vehicle terminal connected to the ECU 20 via an in-vehicle bus 28.

[0030] As described above, the control program 26 controls the airflow rate of the radiator fan 17. More specifically, the control program 26 calculates the airflow rate of the radiator fan 17 (hereinafter referred to as the required airflow rate) according to the required cooling capacity of the radiator 16. More specifically, the control program 26 calculates the required airflow rate according to the coolant temperature detected by the coolant temperature sensor 18. The required airflow rate may be one of a plurality of modes obtained by dividing the rotation speed of the fan motor into stages, such as the above-mentioned OFF, LO, MID, and HIGH modes.

[0031] The control program 26 also calculates a limit airflow rate for the radiator fan 17 in accordance with the vehicle speed detected by the vehicle speed sensor 19. The limit airflow rate is set in advance for each vehicle speed as the airflow rate for the radiator fan 17 at which the operating sound of the radiator fan 17 is drowned out by road noise during high-speed driving. This allows the operating sound of the radiator fan 17 to be drowned out by road noise. The limit airflow rate may be one of a number of modes in which the rotation speed of the fan motor is divided into stages, such as the above-mentioned OFF, LO, MID, and HIGH modes.

[0032] The control program 26 calculates the air volume (hereinafter referred to as the normal air volume) based on the required air volume and the limit air volume. For example, when the limit air volume is larger than the required air volume, the control program 26 may calculate the limit air volume as the normal air volume. Furthermore, when the limit air volume is smaller than the required air volume, the control program 26 may calculate the required air volume as the normal air volume.

[0033] Furthermore, the control program 26 acquires weather information from an external server. The control program 26 also acquires whether or not it is raining from the acquired weather information. More specifically, the control program 26 may determine that it is raining if the weather information indicates that the amount of precipitation in the area in which the vehicle is currently traveling is equal to or greater than a predetermined amount.

[0034] Furthermore, the control program 26 reduces the airflow rate of the radiator fan 17 when it is raining. Specifically, when the amount of precipitation is equal to or greater than a predetermined amount, the control program 26 calculates an airflow rate (hereinafter referred to as a corrected airflow rate) that is lower than the normal airflow rate by a predetermined amount. The predetermined airflow rate may be set according to the amount of precipitation. The corrected airflow rate may be one of a plurality of modes that divide the rotation speed of the fan motor into stages, such as the above-mentioned OFF, LO, MID, and HIGH. The corrected airflow rate may be, for example, one of the above-mentioned modes lower than the normal airflow rate.

[0035] According to the control program 26, the air volume of the radiator fan 17 is reduced when it is raining, thereby reducing the power consumption of the vehicle 10 and the noise of the radiator fan 17.

[0036] [Radiator fan airflow control] The flow of radiator fan air volume control, which is an example of an embodiment, will be described with reference to FIG.

[0037] The radiator fan air volume control is an operation performed by the above-mentioned ECU 20. In step S101, the CPU 21 detects the coolant temperature from the coolant temperature sensor 18. In step S102, the CPU 21 calculates the required air volume based on the coolant temperature detected by the coolant temperature sensor 18.

[0038] In step S103, the CPU 21 detects the speed of the vehicle 10 from the vehicle speed sensor 19. In step S104, the CPU 21 calculates the critical air flow rate of the radiator fan 17 based on the vehicle speed detected by the vehicle speed sensor 19.

[0039] In step S105, the CPU 21 calculates the normal airflow rate based on the required airflow rate and the limit airflow rate. In step S106, the CPU 21 acquires whether or not it is raining from the weather information.

[0040] In step S107, the CPU 21 determines whether the precipitation is equal to or greater than a predetermined amount. If the CPU 21 determines YES in step S107, the process proceeds to step S108. On the other hand, if the CPU 21 determines NO in step S107, the process proceeds to step S109.

[0041] In step S108, CPU 21 reduces the airflow rate of radiator fan 17. Specifically, CPU 21 drives radiator fan 17 in the mode one step lower than the normal airflow rate. As a result, by reducing the airflow rate of radiator fan 17 during rainfall, it is possible to reduce the power consumption of vehicle 10 and reduce the noise of radiator fan 17.

[0042] In step S109, the CPU 21 drives the radiator fan 17 at the normal airflow rate.

[0043] It should be noted that the present invention is not limited to the above-described embodiment and its modifications, and various changes and modifications are possible within the scope of the claims of this application. [Explanation of symbols]

[0044] 10 vehicle, 11 engine, 12 motor, 14 battery, 15 coolant circuit, 16 radiator, 17 radiator fan, 18 coolant temperature sensor, 19 vehicle speed sensor, 20 ECU (control unit), 21 CPU, 22 memory, 23 in-vehicle communication interface, 24 wireless communication interface, 25 internal bus, 26 control program, 27 control program data, 28 in-vehicle bus

Claims

[Claim 1] A control device for controlling an air volume of a radiator fan of a vehicle including a coolant circuit that circulates coolant, a radiator that dissipates heat from the coolant, and a radiator fan that blows air toward the radiator, calculating an air volume of the radiator fan based on the temperature of the cooling water and the vehicle speed, acquiring weather information, and reducing the calculated air volume of the radiator fan when it is determined from the weather information that rain is expected; Control device.

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