Cooling System

Abstract

To inhibit a cooling water temperature of a second cooling device from becoming relatively high when a communication abnormality has occurred between a first control device and a second control device.SOLUTION: A cooling system includes: a first water temperature sensor detecting a cooling water temperature of a first cooling device; a second water temperature sensor detecting a cooling water temperature of a second cooling device; a first control device acquiring the cooling water temperature of the second cooling device from the second water temperature sensor; and a second control device acquiring the cooling water temperature of the first cooling device from the first water temperature sensor and acquiring the cooling water temperature of the second cooling device from the first control device through communication to control a first fan on the basis of the cooling water temperature of the first cooling device and control a second fan on the basis of the cooling water temperature of the second cooling device. When there is a communication abnormality between the first control device and the second control device, the second control device at least forcedly drives the second fan.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a cooling system. [Background technology]

[0002] Conventionally, a cooling system of this type has been proposed that is mounted on a vehicle having an engine, a motor, and a PCU incorporating an inverter for driving the motor, and that includes a first cooling device having a first radiator and a first fan that blows air to the first radiator and cools the engine, and a second cooling device having a second radiator and a second fan that blows air to the second radiator and cools the motor and the PCU (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-119242 A Summary of the Invention [Problem to be solved by the invention]

[0004] Such a cooling system may include a first control device that acquires the coolant temperature of the second cooling device from a water temperature sensor for the second cooling device, and a second control device that acquires the coolant temperature of the first cooling device from the water temperature sensor for the first cooling device and acquires the coolant temperature of the second cooling device from the first control device through communication, controls the first fan based on the coolant temperature of the first cooling device, and controls the second fan based on the coolant temperature of the second cooling device. In this configuration, if a communication abnormality occurs between the first control device and the second control device, the second control device cannot acquire the coolant temperature of the second cooling device, and therefore, depending on the control method of the second fan, the coolant temperature of the second cooling device may become relatively high.

[0005] A main object of the cooling system of the present invention is to prevent the coolant temperature of the second cooling device from becoming relatively high when a communication abnormality occurs between the first control device and the second control device. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the cooling system of the present invention employs the following means.

[0007] The cooling system of the present invention comprises: The vehicle is equipped with a motor device having an engine and a motor, a first cooling device that has a first radiator and a first fan for cooling a cooling water of the first radiator and cools one of the engine and the motor device; a second cooling device that has a second radiator and a second fan for cooling the cooling water of the second radiator and cools the other of the engine and the motor device; A cooling system comprising: a first water temperature sensor that detects a cooling water temperature of the first cooling device; A second water temperature sensor that detects a cooling water temperature of the second cooling device; A first control device that acquires a cooling water temperature of the second cooling device from the second water temperature sensor; a second control device that acquires a coolant temperature of the first cooling device from the first water temperature sensor and acquires a coolant temperature of the second cooling device from the first control device through communication, and controls the first fan based on the coolant temperature of the first cooling device and controls the second fan based on the coolant temperature of the second cooling device; Equipped with the second control device forcibly drives at least the second fan when a communication abnormality occurs between the second control device and the first control device; The gist of the present invention is as follows.

[0008] The cooling system of the present invention includes a first control device that acquires the coolant temperature of the second cooling device from a second water temperature sensor, and a second control device that acquires the coolant temperature of the first cooling device from the first water temperature sensor and acquires the coolant temperature of the second cooling device from the first control device through communication, controls the first fan based on the coolant temperature of the first cooling device, and controls the second fan based on the coolant temperature of the second cooling device. When a communication abnormality occurs between the first control device and the second control device, the second control device forcibly drives at least the second fan. This makes it possible to prevent the coolant temperature of the second cooling device from becoming relatively high when a communication abnormality occurs between the first control device and the second control device, that is, when the second control device cannot acquire the coolant temperature of the second cooling device.

[0009] In the cooling system of the present invention, the second control device may control the second fan to rotate at a maximum rotation speed when a communication abnormality occurs between the second control device and the first control device, thereby more sufficiently preventing the coolant temperature of the second cooling device from becoming relatively high.

[0010] In the cooling system of the present invention, the second control device may control the first fan based on the coolant temperature of the first cooling device even when a communication abnormality occurs between the second control device and the first control device. In this way, when a communication abnormality occurs between the first control device and the second control device, power consumption of the first fan can be reduced compared to a case where the first fan and the second fan are forcibly driven. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing the configuration of an automobile 10 equipped with a cooling system 18 according to an embodiment of the present invention. [Diagram 2] 4 is a flowchart showing an example of a fan control routine executed by the engine ECU 40. [Diagram 3] FIG. 13 is a diagram showing the outline of the configuration of an automobile 10B equipped with a cooling system 18B of a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Next, a mode for carrying out the present invention will be described using examples. EXAMPLES

[0013] 1 is a schematic diagram showing the configuration of an automobile 10 equipped with a cooling system 18 according to an embodiment of the present invention. The automobile 10 of the embodiment is configured as a series hybrid vehicle or a parallel hybrid vehicle equipped with an engine 11 and a motor 12. In addition to the engine 11 and the motor 12, the automobile 10 also includes a power control unit (hereinafter referred to as "PCU") 13, a high-voltage battery 14, an auxiliary battery 15, a DC / DC converter 16, a cooling device 20, a cooling device 30, an engine electronic control unit (hereinafter referred to as "engine ECU") 40, a motor electronic control unit (hereinafter referred to as "motor ECU") 44, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 50. In the embodiment, the engine 11, the motor 12, the PCU 13, the cooling device 20, and the cooling device 30 are arranged in an engine room at the front of the vehicle. The cooling system 18 of the embodiment corresponds to the cooling device 20, the cooling device 30, a water temperature sensor 27 (to be described later), a water temperature sensor 37 (to be described later), the engine ECU 40, and the HVECU 50.

[0014] The engine 11 is configured as, for example, an internal combustion engine. The motor 12 is configured as, for example, a synchronous generator motor. The PCU 13 has an inverter that converts DC power into AC power to drive the motor 12, a boost converter that boosts the power from the high-voltage battery 14 and supplies it to the inverter, and the like. The high-voltage battery 14 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery, and is connected to the PCU 13 via a high-voltage power line. The auxiliary battery 15 is configured as, for example, a lithium-ion secondary battery, a nickel-hydrogen secondary battery, or a lead storage battery, and is connected to a low-voltage power line. The DC / DC converter 16 steps down the power of the high-voltage power line and supplies it to the low-voltage power line.

[0015] The cooling device 20 is configured as a device for cooling the engine 11, and includes a circulation flow path 21 for cooling water, a water pump 22, a radiator 23, and a fan 24. The circulation flow path 21 is formed to include the engine 11 and the radiator 23. The water pump 22 is provided in the circulation flow path 21, and is driven by using power from the auxiliary battery 15 to circulate the cooling water in the circulation flow path 21. The radiator 23 is disposed at the front part of the engine room, and cools the cooling water by heat exchange with the air caused by running wind or air by the fan 24. The fan 24 is driven to rotate by a motor 25 by using power from the auxiliary battery 15 to blow air to the radiator 23, thereby cooling the cooling water in the radiator 23. The motor 25 is configured as, for example, a DC motor.

[0016] The cooling device 30 is configured as a device for cooling the motor 12 and the PCU 13, and includes a circulation flow path 31 for cooling water, a water pump 32, a radiator 33, and a fan 34. The circulation flow path 31 is formed to include the motor 12, the PCU 13, and the radiator 33. The water pump 32 is provided in the circulation flow path 31, and is driven by power from the auxiliary battery 15 to circulate the cooling water in the circulation flow path 31. The radiator 33 is arranged adjacent to the radiator 23 in the left-right direction of the vehicle at the front part of the engine room, and cools the cooling water by heat exchange with the air caused by running wind or the air by the fan 34. The fan 34 is arranged adjacent to the fan 24 in the left-right direction of the vehicle, and is rotationally driven by the motor 35 using power from the auxiliary battery 15 to blow air to the radiator 33 and cool the cooling water in the radiator 33. The motor 35 is configured as, for example, a DC motor.

[0017] Although not shown, the engine ECU 40 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. Various signals are input to the engine ECU 40 via an input port. Examples of the signals input to the engine ECU 40 include signals from various sensors that detect the state of the engine 11, and a coolant temperature Tw1 from a water temperature sensor 27 that detects the temperature of the coolant of the cooling device 20. Various signals are output from the engine ECU 40 via an output port. Examples of the signals output from the engine ECU 40 include various control signals for controlling the operation of the engine 11, a control signal to the water pump 22 of the cooling device 20, a control signal to the fan 24 (motor 25) of the cooling device 20, and a control signal to the fan 34 (motor 35) of the cooling device 30. The engine ECU 40 is connected to the HVECU 50 via CAN communication so as to be able to communicate with each other.

[0018] Although not shown, the motor ECU 44 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports. Various signals are input to the motor ECU 44 via the input ports. Examples of the signals input to the motor ECU 44 include signals from various sensors that detect the states of the motor 12 and the PCU 13. Various signals are output from the motor ECU 44 via the output ports. Examples of the signals output from the motor ECU 44 include various control signals for driving and controlling the PCU 13. The motor ECU 44 is connected to the HVECU 50 via CAN communication so as to be able to communicate with them.

[0019] The HVECU 50 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Various signals are input to the HVECU 50 via the input ports. An example of the signal input to the HVECU 50 is a coolant temperature Tw2 from a water temperature sensor 37 that detects the temperature of the coolant in the cooling device 30. Various control signals are output from the HVECU 50 via the output ports. Examples of the signal output from the HVECU 50 include a control signal to the DC / DC converter 16 and a control signal to the water pump 32 of the cooling device 30. As described above, the HVECU 50 is connected to the engine ECU 40 and the motor ECU 44 so as to be able to communicate with them via CAN communication.

[0020] In the cooling system 18 thus configured and mounted on the automobile 10 of the embodiment, the HVECU 50 basically controls the water pump 32 based on the coolant temperature Tw2 of the cooling device 30 from the water temperature sensor 37, and transmits the coolant temperature Tw2 to the engine ECU 40. The engine ECU 40 also controls the water pump 22 and the fan 24 (motor 25) based on the coolant temperature Tw1 of the cooling device 20 from the water temperature sensor 27, and controls the fan 34 (motor 35) based on the coolant temperature Tw2 of the cooling device 30 from the HVECU 50. Hereinafter, such control of the fan 24 and the fan 34 is referred to as "normal control." The water pump 22 and the fan 24 are controlled to stop when the coolant temperature Tw1 is less than the thresholds Twth11 and Twth12, respectively, and to rotate at a higher rotation speed as the coolant temperature Tw1 is higher when the coolant temperature Tw1 is equal to or higher than the thresholds Twth11 and Twth12. The water pump 32 and the fan 34 are controlled to stop when the coolant temperature Tw2 is less than the threshold value Twth21, Twth22, and to rotate at a higher rotation speed as the coolant temperature Tw2 is higher when the coolant temperature Tw2 is equal to or higher than the threshold value Twth21, Twth22.

[0021] Next, a description will be given of the operation of the cooling system 18 mounted on the automobile 10 of the embodiment thus configured, and the control of the fans 24, 34 of the cooling devices 20, 30 by the engine ECU 40. Figure 2 is a flowchart showing an example of a fan control routine executed by the engine ECU 40. This routine is executed repeatedly.

[0022] 2, the engine ECU 40 first determines whether or not a communication abnormality has occurred with the HVECU 50 (step S100). This process can be performed, for example, by determining whether or not communication with the HVECU 70 has been interrupted for a predetermined period of time.

[0023] If it is determined in step S100 that no communication abnormality has occurred with the HVECU 50, it is determined that the fans 24 and 34 are to be normally controlled (step S110), and this routine ends. In this case, the engine ECU 40 controls the fan 24 (motor 25) based on the coolant temperature Tw1 of the cooling device 20 from the water temperature sensor 27, as described above, and controls the fan 34 (motor 35) based on the coolant temperature Tw2 of the cooling device 30 from the HVECU 50.

[0024] When it is determined in step S100 that a communication abnormality occurs with the HVECU 50, it is determined that the fan 24 is normally controlled and the fan 34 is forcibly driven at the maximum rotation speed (step S120), and this routine is terminated. In this case, the engine ECU 40 controls the fan 24 (motor 25) based on the coolant temperature Tw1 of the cooling device 20 from the water temperature sensor 27, and controls the fan 34 (motor 35) to rotate at the maximum rotation speed. When a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the engine ECU 40 cannot grasp the coolant temperature Tw2 of the cooling device 30. At this time, in the embodiment, the engine ECU 40 forcibly drives the fan 34, thereby preventing the coolant temperature Tw2 of the cooling device 30 from becoming relatively high. Moreover, by controlling the fan 34 to rotate at the maximum rotation speed, it is possible to more sufficiently prevent the coolant temperature Tw2 of the cooling device 30 from becoming relatively high. Furthermore, even when a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the engine ECU 40 can control the fan 24 normally, thereby reducing power consumption of the fan 24 compared to a case in which the fan 24 is forcibly driven.

[0025] In the cooling system 18 mounted on the automobile 10 of the embodiment described above, the engine ECU 40 controls the fan 24 (motor 25) based on the coolant temperature Tw1 of the cooling device 20 from the water temperature sensor 27, and controls the fan 34 (motor 35) based on the coolant temperature Tw2 of the cooling device 30 from the HVECU 50, and when a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the engine ECU 40 forcibly drives the fan 34. This makes it possible to prevent the coolant temperature Tw2 of the cooling device 30 from becoming relatively high.

[0026] In the cooling system 18 mounted on the automobile 10 of the embodiment, when a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the engine ECU 40 controls the fan 34 to rotate at the maximum rotation speed. However, in this case, the engine ECU 40 may also control the fan 34 to rotate at a rotation speed slightly lower than the maximum rotation speed.

[0027] In the cooling system 18 mounted on the automobile 10 of the embodiment, even when a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the engine ECU 40 normally controls the fan 24. However, in this case, the engine ECU 40 may forcibly drive the fan 24 in the same manner as the fan 34.

[0028] In the cooling system 18 mounted on the automobile 10 of the embodiment, as shown in FIG. 1, the engine ECU 40 controls the fan 24 (motor 25) of the cooling device 20 and the fan 34 (motor 35) of the cooling device 30. However, as shown in an automobile 10B mounted with a cooling system 18B of a modified example in FIG. 3, the HVECU 50 may control the fan 24 of the cooling device 20 and the fan 34 of the cooling device 30. In this case, basically, the engine ECU 40 transmits the coolant temperature Tw1 of the cooling device 20 from the water temperature sensor 27 to the HVECU 50, and the HVECU 50 controls the fan 24 based on the coolant temperature Tw1 of the cooling device 20 from the engine ECU 40 and controls the fan 34 based on the coolant temperature Tw2 of the cooling device 30 from the water temperature sensor 37. When a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the HVECU 50 forcibly drives the fan 24. This makes it possible to prevent the cooling water temperature Tw1 of the cooling device 20 from becoming relatively high. Moreover, if the fan 24 is controlled to rotate at the maximum rotation speed at this time, the cooling water temperature Tw1 of the cooling device 20 can be more sufficiently prevented from becoming relatively high. Furthermore, even when a communication abnormality occurs between the HVECU 50 and the engine ECU 40, the HVECU 50 normally controls the fan 34. This makes it possible to reduce the power consumption of the fan 34 compared to when the fan 34 is forcibly driven. Note that, at this time, the HVECU 50 may forcibly drive the fan 34 in the same way as the fan 24.

[0029] In the cooling system 18, 18B mounted on the automobiles 10, 10B of the embodiment and the modified example, when the coolant temperature Tw1 is equal to or higher than the threshold value Twth2, the fan 24 is controlled to rotate at a higher rotation speed as the coolant temperature Tw1 is higher, and when the coolant temperature Tw2 is equal to or higher than the threshold value Twth4, the fan 34 is controlled to rotate at a higher rotation speed as the coolant temperature Tw2 is higher. However, the fan 24 may be controlled to rotate at a constant rotation speed when the coolant temperature Tw1 is equal to or higher than the threshold value Twth2. Also, the fan 34 may be controlled to rotate at a constant rotation speed when the coolant temperature Tw2 is equal to or higher than the threshold value Twth4. The same can be considered for the water pumps 22, 32.

[0030] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be described below. In the embodiment, the engine 11 corresponds to the "engine", the motor 12 and the PCU 13 correspond to the "motor device", the cooling device 20 corresponds to the "first cooling device", the cooling device 30 corresponds to the "second cooling device", the water temperature sensor 27 corresponds to the "first water temperature sensor", the water temperature sensor 37 corresponds to the "second water temperature sensor", the HVECU 50 corresponds to the "first control device", and the engine ECU 40 corresponds to the "second control device".

[0031] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0032] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0033] The present invention can be used in the cooling system manufacturing industry and the like. [Explanation of symbols]

[0034] 10,10B automobile, 11 engine, 12 motor, 13 PCU, 14 high voltage battery, 15 auxiliary battery, 16 DC / DC converter, 18,18B cooling system, 20,30 cooling device, 21,31 circulation flow path, 22,32 water pump, 23,33 radiator, 24,34 fan, 25,35 motor, 27,37 water temperature sensor, 40 engine ECU, 44 motor ECU, 50 HVECU.

Claims

[Claim 1] The vehicle is equipped with a motor device having an engine and a motor, a first cooling device that has a first radiator and a first fan for cooling a cooling water of the first radiator and cools one of the engine and the motor device; a second cooling device that has a second radiator and a second fan for cooling the cooling water of the second radiator and cools the other of the engine and the motor device; A cooling system comprising: a first water temperature sensor that detects a cooling water temperature of the first cooling device; a second water temperature sensor that detects a cooling water temperature of the second cooling device; A first control device that acquires a cooling water temperature of the second cooling device from the second water temperature sensor; a second control device that acquires a coolant temperature of the first cooling device from the first water temperature sensor and acquires a coolant temperature of the second cooling device from the first control device through communication, and controls the first fan based on the coolant temperature of the first cooling device and controls the second fan based on the coolant temperature of the second cooling device; Equipped with the second control device controls the second fan to rotate at a maximum rotation speed when a communication abnormality occurs between the second control device and the first control device, and controls the first fan based on a cooling water temperature of the first cooling device. Cooling system.

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