Vehicle control device

Abstract

To improve overall heat exchange capacity of a plurality of heat exchangers through which a coolant flows.SOLUTION: A vehicle control device 10 includes radiators 14 and 16 externally radiating heat from a coolant which has undergone heat exchange with an on-vehicle device 12 mounted on a vehicle. A control section 48 acquires solar radiation levels for the radiators 14 and 16, and controls a flow direction of the coolant so that the coolant flows from the radiator 14 to the radiator 16 (in a direction of a solid-line arrow) when the radiator 14 receives higher solar radiation than the radiator 16, and the coolant flows from the radiator 16 to the radiator 14 (in a direction of a dashed-line arrow) when the radiator 16 receives higher solar radiation than the radiator 14.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] Patent Document 1 describes a technology in which a refrigerant circulation circuit has a chiller heat exchange passage, a radiator heat exchange passage, and a heater heat exchange passage as refrigerant passages, and when heat is to be released from the target equipment, the radiator heat exchange passage and the chiller heat exchange passage are selected as the refrigerant passages and the chiller is not operated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-047588 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology described in Patent Document 1 suppresses refrigerant pressure loss by flowing the refrigerant in parallel through the radiator heat exchange passage and the chiller heat exchange passage, and by using the chiller heat exchange passage as a bypass passage, but it is not possible to arbitrarily change the order in which the refrigerant flows through the multiple heat exchange passages. Therefore, the technology described in Patent Document 1 leaves room for improvement in terms of improving the overall heat exchange amount of the multiple heat exchangers through which the refrigerant flows when the amount of solar radiation to the multiple heat exchangers through which the refrigerant flows differs.

[0005] The present disclosure has been made in consideration of the above circumstances, and an object of the present disclosure is to provide a vehicle control device that can improve the overall heat exchange rate of a plurality of heat exchangers through which a refrigerant flows. [Means for solving the problem]

[0006] A vehicle control device according to a first aspect includes a plurality of heat exchangers that radiate heat from a refrigerant that has exchanged heat with onboard equipment installed in the vehicle to the outside, and a control unit that acquires the amount of solar radiation on the plurality of heat exchangers and controls the refrigerant to flow through the plurality of heat exchangers in order of the amount of solar radiation with the highest.

[0007] In the first aspect, the amount of solar radiation on multiple heat exchangers is obtained, and the refrigerant that has exchanged heat with on-board equipment is controlled to flow through the multiple heat exchangers in descending order of the amount of solar radiation.As a result, as will be explained in the examples below, the overall heat exchange amount of the multiple heat exchangers through which the refrigerant flows can be improved. [Effects of the Invention]

[0008] The present disclosure has an effect of improving the overall heat exchange amount of a plurality of heat exchangers through which a refrigerant flows. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a vehicle control device according to an embodiment; [Figure 2] 4 is a flowchart showing a heat exchange control process executed by a control unit. [Figure 3] FIG. 10 is a diagram showing the results of a simulation carried out by the inventors of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0010] An example of an embodiment of the present disclosure will be described in detail below with reference to the drawings. Fig. 1 shows a vehicle control device 10 mounted on a vehicle. In this embodiment, the vehicle mounted with the vehicle control device 10 is a vehicle designed to be able to travel on the surface of the moon, a so-called lunar rover, but the vehicle control device 10 can also be mounted on a so-called ground vehicle designed for traveling on the ground.

[0011] The vehicle control device 10 targets to cool on-board equipment 12 mounted on the vehicle, and the on-board equipment 12 is provided with a flow passage through which coolant, which is an example of a refrigerant in the present disclosure, flows. Note that the refrigerant in the present disclosure may be something other than water. The coolant cools the on-board equipment 12 by receiving heat from the on-board equipment 12 while flowing through the flow passage provided adjacent to the on-board equipment 12. An example of the on-board equipment 12 is a battery, but the on-board equipment 12 may be other equipment.

[0012] One end of a first pipe 30 is connected to the coolant outflow side of the in-vehicle device 12, and the other end of the first pipe 30 is connected to the first three-way valve 20. The first three-way valve 20 is connected to one end of a second pipe 32 and one end of a sixth pipe 40, and is switchable between a first state in which the first pipe 30 communicates with the second pipe 32 and a second state in which the first pipe 30 communicates with the sixth pipe 40.

[0013] The other end of the second pipe 32 is connected to the second three-way valve 22. The second three-way valve 22 is connected to one end of the third pipe 34 and one end of the seventh pipe 42, and is switchable between a first state in which the second pipe 32 communicates with the third pipe 34 and a second state in which the second pipe 32 communicates with the seventh pipe 42.

[0014] The other end of the third pipe 34 is connected to the third three-way valve 24, and the pump 18, the first radiator 14, and the second radiator 16 are provided in this order along the third pipe 34. The pump 18 can be switched between a forward rotation state in which the cooling water in the third pipe 34 flows from the second three-way valve 22 to the third three-way valve 24, and a reverse rotation state in which the cooling water flows from the third three-way valve 24 to the second three-way valve 22.

[0015] The first radiator 14 is disposed, for example, on one side of the vehicle, and the second radiator 16 is disposed, for example, on the other side of the vehicle. The coolant dissipates heat as it flows through the first radiator 14 and the second radiator 16. The first radiator 14 and the second radiator 16 are examples of the multiple heat exchangers of the present disclosure. The first radiator 14 is provided with a first solar radiation sensor 44 that detects the amount of solar radiation S1 on the first radiator 14, and the second radiator 16 is provided with a second solar radiation sensor 46 that detects the amount of solar radiation S2 on the second radiator 16.

[0016] The third three-way valve 24 is connected to one end of the fourth pipe 36 and the other end of the sixth pipe 40, and is switchable between a first state in which the third pipe 34 is connected to the fourth pipe 36 and a second state in which the third pipe 34 is connected to the sixth pipe 40.

[0017] The other end of the fourth pipe 36 is connected to the fourth three-way valve 26. One end of the fifth pipe 38 and the other end of the seventh pipe 42 are connected to the fourth three-way valve 26, and the fourth three-way valve 26 is switchable between a first state in which the fourth pipe 36 communicates with the fifth pipe 38 and a second state in which the fourth pipe 36 communicates with the seventh pipe 42. The other end of the fifth pipe 38 is connected to the coolant inlet side of the in-vehicle device 12.

[0018] With the above configuration, when the three-way valves 20-26 are each in the first state and the pump 18 is in the forward rotation state, the coolant flows from the first radiator 14 to the second radiator 16. On the other hand, when the three-way valves 20-26 are each in the second state and the pump 18 is in the reverse rotation state, the coolant flows from the second radiator 16 to the first radiator 14. Therefore, the three-way valves 20-26 and the pump 18 function as a switching unit that can switch between the flow of coolant from the first radiator 14 to the second radiator 16 and the flow of coolant from the second radiator 16 to the first radiator 14.

[0019] The vehicle control device 10 includes a control unit 48. Although not shown, the control unit 48 includes a central processing unit (CPU), memories such as read-only memory (ROM) and random access memory (RAM), non-volatile storage units such as hard disk drives (HDDs) and solid state drives (SSDs), and an input / output interface (I / F), which are interconnected via a bus for mutual communication. The pump 18, the first three-way valve 20, the second three-way valve 22, the third three-way valve 24, the fourth three-way valve 26, the first solar radiation sensor 44, and the second solar radiation sensor 46 are connected to the input / output interface.

[0020] A heat exchange control program is stored in the ROM or memory of the control unit 48. The control unit 48 reads the heat exchange control program from the ROM or memory and loads it into memory, and the CPU executes the heat exchange control program loaded into memory, thereby performing a heat exchange control process, which will be described later. The control unit 48 obtains the amount of solar radiation on the radiators 14, 16, and controls the flow of coolant through the radiators 14, 16 in descending order of solar radiation amount.

[0021] Next, as an operation of this embodiment, the heat exchange control process that is repeatedly executed by the control unit 48 while the vehicle is powered on will be described with reference to FIG.

[0022] In step 70, the control unit 48 acquires the amount of solar radiation S on the first radiator 14 from the first solar radiation sensor 44, and acquires the amount of solar radiation S2 on the second radiator 16 from the second solar radiation sensor 46. Then, the control unit 48 compares the acquired amounts of solar radiation S1 and S2, and determines whether the amount of solar radiation S1 on the first radiator 14 is greater than the amount of solar radiation S2 on the second radiator 16.

[0023] If the determination in step 70 is affirmative, the process proceeds to step 72. In step 72, the control unit 48 determines whether the current flow direction of the coolant is from the first radiator 14 to the second radiator 16. If the determination in step 72 is affirmative, the three-way valves 20 to 26 are each in the first state, and the pump 18 is in the forward rotation state. Therefore, as shown by the solid arrows in FIG. 2, the coolant flowing out from the on-vehicle device 12 flows in the order of the first pipe 30, the second pipe 32, the third pipe 34, the fourth pipe 36, and the fifth pipe 38, and the coolant flows from the first radiator 14, which has a higher amount of solar radiation, to the second radiator 16. Therefore, if the determination in step 72 is affirmative, the process proceeds to step 76, and the three-way valves 20 to 26 and the pump 18 are maintained in their current states.

[0024] Furthermore, if the determination in step 72 is negative, the first three-way valve 20, the second three-way valve 22, the third three-way valve 24, and the fourth three-way valve 26 are all in the second state, and the pump 18 is rotating in reverse. Therefore, as shown by the dashed arrows in FIG. 2 , the coolant flowing out of the in-vehicle device 12 flows through the first pipe 30, the sixth pipe 40, the third pipe 34, the seventh pipe 42, and the fifth pipe 38 in this order, and the coolant flows from the second radiator 16 to the first radiator 14. Therefore, if the determination in step 72 is negative, the process proceeds to step 78, in which the three-way valves 20 to 26 are switched from the second state to the first state, and the pump 18 is switched from the reverse state to the forward state. As a result, the coolant flows from the first radiator 14, which receives a higher amount of solar radiation, to the second radiator 16.

[0025] Furthermore, if the determination in step 70 is negative, the process proceeds to step 74. In step 74, the control unit 48 determines whether the current flow direction of the coolant is from the second radiator 16 to the first radiator 14. If the determination in step 74 is positive, the three-way valves 20 to 26 are each in the second state, and the pump 18 is in the reverse state. Therefore, the coolant flowing out from the on-board device 12 flows as shown by the dashed arrows in FIG. 2, and the coolant flows from the second radiator 16, which has a higher amount of solar radiation, to the first radiator 14. Therefore, if the determination in step 74 is positive, the process proceeds to step 76, and the three-way valves 20 to 26 and the pump 18 are maintained in their current states.

[0026] On the other hand, if the determination in step 74 is negative, the three-way valves 20 to 26 are each in the first state, and the pump 18 is in the forward rotation state. Therefore, the coolant flowing out of the in-vehicle device 12 flows as shown by the solid arrows in FIG. 2, from the first radiator 14 to the second radiator 16. Therefore, if the determination in step 74 is negative, the process proceeds to step 78, in which the three-way valves 20 to 26 are switched from the first state to the second state, and the pump 18 is switched from the forward rotation state to the reverse rotation state. As a result, the coolant flows from the second radiator 16, which receives a higher amount of solar radiation, to the first radiator 14.

[0027] Thus, the vehicle control device 10 includes the radiators 14, 16 that radiate heat from the refrigerant that has exchanged heat with the on-board devices 12 mounted on the vehicle to the outside, and the control unit 48 that acquires the amount of solar radiation on the radiators 14, 16 and controls the refrigerant to flow through the radiators 14, 16 in descending order of the amount of solar radiation. This makes it possible to improve the overall heat exchange amount of the radiators 14, 16 through which the refrigerant flows.

[0028] In the above embodiment, the solar radiation sensors 44, 46 detect the amount of solar radiation on the first radiator 14 and the second radiator 16, but the present disclosure is not limited to this. For example, the first radiator 14 and the second radiator 16 may each be provided with a temperature sensor that detects the surface temperature, etc., and the surface temperatures of the first radiator 14 and the second radiator 16 may be detected to indirectly detect the amount of solar radiation on the first radiator 14 and the second radiator 16.

[0029] Furthermore, in the above embodiment, an aspect in which two radiators, which are an example of a heat exchanger, are provided has been described, but three or more radiators may be provided. [Example]

[0030] Next, with reference to FIG. 3, the results of simulation calculations performed by the inventors of the present application to confirm the effects of the present disclosure will be described.

[0031] In this simulation, the area is 9m 2 One of the two radiators is exposed to sunlight (for example, solar heat input = 181.7 W / m 2 ) and the other is in an environment where sunlight is not incident (for example, solar heat input = 0 W / m 2 The total heat dissipation was calculated for the case where water was first passed through the radiator in an environment where sunlight was incident (Fig. 3(A)) and the case where water was first passed through the radiator in an environment where sunlight was not incident (Fig. 3(B)).

[0032] As a result, when water was passed through the radiator in an environment where sunlight was incident first, the total heat dissipation was 3540W, whereas when water was passed through the radiator in an environment where sunlight was not incident first, the total heat dissipation was only 3280W. It was confirmed that when water was passed through the radiator in an environment where sunlight was incident first, the heat dissipation was approximately 300W higher. [Explanation of symbols]

[0033] 10 Vehicle control device 12 In-vehicle equipment 14 First radiator (heat exchanger) 16 Second radiator (heat exchanger) 18 Pump 20. First three-way valve 22 Second three-way valve 24 Third three-way valve 26 Fourth three-way valve 48 Control Unit

Claims

[Claim 1] a plurality of heat exchangers that radiate heat of the refrigerant that has exchanged heat with on-board devices mounted in the vehicle to the outside; a control unit that acquires amounts of solar radiation on the plurality of heat exchangers and controls the refrigerant to flow through the plurality of heat exchangers in descending order of the amount of solar radiation; A vehicle control device including:

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