JP5500008B2 - Cooling system - Google Patents

Description

  The present invention relates to a cooling device for an electric device mounted on a vehicle using a rotating electrical machine as a drive source, and more particularly to a cooling device that cools the electric device using an air conditioning refrigeration cycle system.

  In recent years, attention has been focused on hybrid vehicles, fuel cell vehicles, electric vehicles, and the like that travel with the driving force of a motor as one of countermeasures for environmental problems.

  In such a vehicle, electric devices such as a motor, a generator, an inverter, a converter, and a battery generate heat when power is transmitted and received, and it is necessary to cool these electric devices. In this case, it is conceivable to provide a cooling system that circulates cooling water between the electrical equipment and the radiator as in a normal vehicle that uses only the engine. Since it is necessary to provide a dedicated radiator, vehicle mountability may be lowered.

  In view of such a problem, Japanese Patent Application Laid-Open No. 2006-290254 (Patent Document 1) discloses a cooling system for a hybrid vehicle that can improve assemblability, reduce costs, and reduce size by sharing components. . This cooling system includes a compressor capable of sucking and compressing gas refrigerant, a main condenser capable of cooling with ambient air for condensing high-pressure gas refrigerant, and an evaporator capable of cooling a refrigerant by evaporating a low-temperature liquid refrigerant. And a pressure reducing means, wherein a heat exchanger capable of absorbing heat from the motor and a second pressure reducing means are connected in parallel to the pressure reducing means and the evaporator.

  According to the cooling system disclosed in the above publication, the manufacturing cost can be reduced by improving the assemblability by sharing the components. Moreover, size reduction can be achieved.

JP 2006-290254 A

  However, when the evaporator and the heat exchanger capable of absorbing heat from the motor are connected in parallel like the cooling system described in Patent Document 1 described above, a refrigerant is supplied to each of the evaporator and the heat exchanger, In addition, since it is necessary to reduce the pressure to a complete gas, there is a problem that the power performance required for the compressor used for cooling is increased. Therefore, there is a problem that if the compressor is enlarged, the fuel consumption is deteriorated, and if the capacitor is enlarged for improving the compressor power, the mountability is deteriorated.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a cooling device that cools an electric device without deteriorating required compressor power and mountability on a vehicle. is there.

  A cooling device according to an aspect of the present invention is a cooling device for cooling an electric device mounted on a vehicle. The cooling device includes a compressor for circulating the refrigerant, a condenser for condensing the refrigerant, an evaporator for cooling the interior of the vehicle using the refrigerant, and a refrigerant path flowing from the condenser to the compressor. And a cooling unit that is provided in series with the evaporator and cools the electric device using the refrigerant.

  Preferably, the cooling unit includes an electromagnetic valve for decompressing the refrigerant supplied to the cooling unit. The cooling device controls the electromagnetic valve so that the opening degree of the electromagnetic valve becomes the first opening degree when the cooling is performed, and the opening degree of the electromagnetic valve becomes the second opening degree when the cooling is not performed. A control unit for controlling the electromagnetic valve is further included. The first opening is larger than the second opening.

  More preferably, the cooling device further includes a detection unit for detecting the temperature of the refrigerant in the path. The control unit controls the solenoid valve so that the first opening is fully opened when the refrigerant temperature is lower than the threshold, and when the refrigerant temperature is higher than the threshold, the first opening is fully opened. The solenoid valve is controlled so that the opening degree is smaller than that.

  More preferably, the first cross-sectional shape when the opening of the solenoid valve is fully open is formed such that the resistance during circulation of the refrigerant does not become larger than the second cross-sectional shape of the passage forming the path.

  More preferably, the solenoid valve blocks the flow of the refrigerant in the path when the opening degree of the solenoid valve is fully closed. The cooling device further includes a check valve for allowing the refrigerant to flow from the compressor side to the condenser side and for blocking the refrigerant flow from the condenser side to the compressor side. The control unit controls the electromagnetic valve so that the opening degree of the electromagnetic valve is fully closed when cooling is not performed and there is no request for cooling the electrical device.

  More preferably, the control unit determines that there is no request for cooling the electric device when the temperature of the electric device is lower than the threshold value.

  More preferably, the control unit operates the compressor when the electric device is cooled by the cooling unit even when the cooling is not performed.

  More preferably, the cooling unit is provided between the condenser and the evaporator. A valve is provided between the evaporator and the cooling unit for supplying a mist refrigerant to the evaporator when cooling is performed.

  According to the present invention, a cooling unit for cooling an electric device is provided in series with an evaporator on a refrigerant path that circulates from the condenser to the compressor, so that the electric device can be used using a liquid-phase refrigerant when cooling is performed. Can be cooled. Therefore, both the cooling and the cooling of the electric equipment can be performed with the same amount of operation of the compressor as that in the normal cooling when the cooling unit is not provided. In other words, it is not necessary to increase the power performance of the compressor in order to cool the electric device, and it is possible to avoid increasing the size of the compressor or providing a dedicated pump for cooling the electric device. Further, when cooling is not performed, the necessary cooling performance can be ensured by supplying the refrigerant so as to be vaporized in the cooling unit to cool the electric device. Therefore, it is possible to provide a cooling device that cools the electric device without deteriorating the compressor power requirement and the mountability to the vehicle.

It is a figure which shows the whole structure of the cooling device which concerns on 1st Embodiment. It is a functional block diagram of ECU of the cooling device which concerns on 1st Embodiment. It is a flowchart which shows the control structure of the program performed by ECU of the cooling device which concerns on 1st Embodiment. It is a figure which shows the whole structure of the cooling device which concerns on 2nd Embodiment. It is a functional block diagram of ECU of the cooling device which concerns on 2nd Embodiment. It is a flowchart which shows the control structure of the program performed by ECU of the cooling device which concerns on 2nd Embodiment. It is a figure which shows the whole structure of the cooling device which concerns on 3rd Embodiment. It is a functional block diagram of ECU of the cooling device which concerns on 3rd Embodiment. It is a flowchart which shows the control structure of the program performed by ECU of the cooling device which concerns on 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
A cooling device 10 according to the present embodiment shown in FIG. 1 cools an electric device mounted on a vehicle using a rotating electrical machine as a drive source. Examples of the vehicle using the rotating electric machine as a drive source include an electric vehicle, a fuel cell vehicle, and a hybrid vehicle. In the present embodiment, “electrical equipment” will be described using, for example, an inverter 122 for converting DC power to AC power and a motor generator 124 that is a rotating electrical machine, but are not particularly limited to these. is not. For example, the “electric device” may further include a battery as a power storage device, a converter for boosting the voltage of the battery, and a DC / DC converter for stepping down the voltage of the battery. The battery is a secondary battery such as a lithium ion battery or a nickel metal hydride battery. A capacitor may be used instead of the battery. Note that the electric device mounted on the vehicle is not particularly limited to the above-described electric device as long as it is an electric device that generates heat by at least operation.

  When there are a plurality of electrical devices to be cooled, it is desirable that the plurality of electrical devices have a common temperature range to be cooled. The target temperature range for cooling is a temperature range suitable as a temperature environment for operating the electrical equipment.

  Cooling device 10 according to the present embodiment includes an air-conditioning refrigeration cycle system 12 for cooling the interior of a vehicle, and cooling for cooling electrical equipment using a refrigerant circulating in air-conditioning refrigeration cycle system 12. Part 120 and ECU 400.

  The air conditioning refrigeration cycle system 12 includes a compressor 20, a condenser 40, an evaporator 80, and an expansion valve 150. The cooling unit 120 is provided in series with the evaporator 80 on the refrigerant path flowing from the condenser 40 to the compressor 20, and cools the electric device using the refrigerant.

  Specifically, the capacitor 40 and the evaporator 80 are connected by the first connection passage 302, the cooling passage 126 of the cooling unit 120, and the second connection passage 304. In the present embodiment, the receiver 60 is described as being provided at the outlet of the capacitor 40, but the presence or absence of the receiver 60 is not particularly limited. The cooling unit 120 is provided between the receiver 60 and the evaporator 80.

  The evaporator 80 and the compressor 20 are connected by a third connection passage 306. Further, the compressor 20 and the condenser 40 are connected by a fourth connection passage 308.

  The compressor 20 operates using a motor mounted on the vehicle as a power source, sucks and compresses the gaseous refrigerant flowing from the evaporator 80 via the third connection passage 306 during operation, and discharges it to the fourth connection passage 308. The compressor 20 operates based on a control signal C1 from the ECU 400. In addition, the compressor 20 may use an engine as a power source.

  For cooling using the air-conditioning refrigeration cycle system 12, for example, when a switch for performing cooling is turned on, or an automatic control mode for automatically adjusting the temperature in the vehicle interior to the set temperature is selected. And when the temperature in the passenger compartment is higher than the set temperature.

  The condenser 40 condenses (liquefies) the refrigerant by dissipating heat from the refrigerant compressed in the compressor 20. Capacitor 40 includes a tube through which the refrigerant flows, and fins for exchanging heat between the refrigerant flowing through the tube and the air around capacitor 40. The condenser 40 is provided, for example, adjacent to an engine cooling radiator mounted on the vehicle, and performs heat exchange between the cooling air supplied by the traveling air of the vehicle or the cooling fan and the refrigerant. Due to the heat exchange in the condenser 40, the temperature of the refrigerant decreases and the refrigerant liquefies.

  The specification (ie, size or heat dissipation performance) of the capacitor 40 may be determined such that at least the temperature of the liquid-phase refrigerant after passing through the capacitor 40 is lower than the temperature required for cooling the electrical equipment. desirable. It is desirable that the temperature required for cooling the electric device is at least a temperature lower than the upper limit value of the target temperature range as the temperature range of the electric device. Preferably, the capacitor 40 has a specification such that the heat dissipation amount is larger than the capacitor 40 of the air-conditioning refrigeration cycle system 12 when the cooling unit 120 is not provided, by the amount of heat expected to be received in the cooling unit 120. Is desirable. In this way, it is possible to appropriately cool the electric equipment without increasing the power performance of the compressor 20 while maintaining the cooling performance.

  The receiver 60 is provided at the outlet of the capacitor 40, separates the refrigerant flowing from the capacitor 40 into a gas phase refrigerant and a liquid phase refrigerant, and stores the liquid phase refrigerant among the separated refrigerants. The liquid-phase refrigerant in the receiver 60 flows through the first connection passage 302, passes through the cooling unit 120, and then flows through the second connection passage 304 to be supplied to the expansion valve 150.

  The expansion valve 150 is a valve for expanding a high-temperature / high-pressure liquid-phase refrigerant flowing through the second connection passage 304 by injecting it from a small hole to change it into a low-temperature / low-pressure mist refrigerant. The expansion valve 150 includes a valve main body 152 provided at a position upstream of the evaporator 80 and a temperature sensitive member 154 provided at a position downstream of the evaporator 80.

  In the expansion valve 150, the flow rate of the refrigerant in the valve main body 152 is determined according to the temperature of the refrigerant in the temperature sensitive member 154. The flow rate of the refrigerant is determined so that all of the refrigerant changed into a mist is completely vaporized in the evaporator 80.

  In the expansion valve 150, for example, the flow rate of the refrigerant by moving the valve body of the valve main body 152 using the change in the pressure of the gas according to the temperature of the refrigerant in the temperature-sensitive member 154 in which the gas is sealed inside the container. Is determined. The relationship between the temperature of the refrigerant and the amount of movement of the valve body is adjusted in advance according to the size of the container or the amount of gas.

  The evaporator 80 absorbs the heat of the air in the vehicle interior introduced so as to come into contact with the evaporator 80 when the mist refrigerant evaporates. The air whose temperature has decreased due to heat absorption is returned to the vehicle interior to cool the vehicle interior.

  The evaporator 80 includes a tube through which the refrigerant flows, and fins for exchanging heat between the refrigerant flowing through the tube and the air around the evaporator 80. A mist-like refrigerant circulates in the tube. As the refrigerant circulating in the tube evaporates, the heat of the air in the vehicle interior is absorbed through the fins. The vaporized refrigerant flows through the third connection passage 306 to the compressor 20.

  Cooling unit 120 is provided so that heat can be exchanged between inverter 122 and motor generator 124 (in the following description, these electric devices may be simply referred to as “electric devices”) and the refrigerant. . In the present embodiment, for example, cooling unit 120 has a structure capable of exchanging heat between the electric device and the refrigerant by cooling passage 126 formed so that the refrigerant contacts the housing of the electric device. As will be described, the cooling unit 120 has a structure in which the heat exchanger and the refrigerant can be brought into contact with each other when the electric device and the heat exchanger are connected via heat transfer means such as a heat pipe. It may be.

  In the present embodiment, cooling unit 120 may form cooling passage 126 so as to cool motor generator 124 after cooling inverter 122, or motor generator 124 after cooling motor generator 124. The cooling passage 126 may be formed so as to cool the inverter, or the cooling passage 126 may be formed so as to cool the inverter 122 and the motor generator 124 in parallel. Preferably, the cooling unit 120 cools the electrical device with the lower upper limit value of the target temperature range among the electrical devices to be cooled, and then the electrical device with the higher upper limit value of the target temperature range. It is desirable to provide cooling.

  The cooling unit 120 includes a cooling passage 126, a solenoid valve 132, and a temperature sensor 134. Both ends of the cooling passage 126 are connected to the first connection passage 302 and the second connection passage 304, respectively.

  Cooling passage 126 has a portion adjacent to each housing of inverter 122 and motor generator 124. Heat exchange can be performed between the refrigerant flowing through the cooling passage 126 and the inverter 122 and the motor generator 124 in this portion.

  Solenoid valve 132 is provided on the inlet side of cooling passage 126, that is, on the upstream side of the portion of cooling passage 126 adjacent to the casing of inverter 122 and motor generator 124. The opening degree of the electromagnetic valve 132 is controlled by the ECU 400 from the fully open state to the fully closed state. That is, the electromagnetic valve 132 depressurizes the refrigerant by reducing the opening degree based on the control signal S1 received from the ECU 400, or allows the refrigerant to pass through without being depressurized by being fully opened.

  When the solenoid valve 132 is in a fully open state, the resistance received from the passage when the refrigerant flows through the electromagnetic valve 132 is the same as the resistance received from the passage when the refrigerant flows through a portion other than the electromagnetic valve 132 of the cooling passage 126. It is formed to become.

  Specifically, the electromagnetic valve 132 is formed so that the internal shape when the electromagnetic valve 132 is in the fully open state matches the internal shape of the cooling passage 126 other than the electromagnetic valve 132. For example, when the internal shape of the cooling passage 126 is a circle, the inner diameter when the solenoid valve 132 is in a fully open state is formed to be a circle that matches the inner diameter of the first connection passage 302. If it does in this way, the change of the pressure of the refrigerant before and after electromagnetic valve 132 when electromagnetic valve 132 is a full open state can be controlled.

  Temperature sensor 134 is provided at the outlet side of cooling passage 126, that is, at a position downstream of the portion of cooling passage 126 adjacent to the casing of inverter 122 and motor generator 124, and detects the temperature of the refrigerant at that position. . The temperature sensor 134 transmits a signal indicating the detected refrigerant temperature T <b> 1 to the ECU 400.

  The ECU 400 generates the control signal C1 to operate the compressor 20 when the cooling is performed and when the electric device is cooled by the cooling unit 120 and transmits the control signal C1 to the compressor 20, or receives the temperature of the refrigerant from the temperature sensor 134. The flow rate in the electromagnetic valve 132 is determined based on T1, and a control signal S1 for operating the electromagnetic valve 132 so as to be the determined flow rate is generated and transmitted to the electromagnetic valve 132.

  In cooling device 10 according to the present embodiment having the above-described configuration, ECU 400 is characterized in that it operates as follows.

  That is, ECU 400 controls electromagnetic valve 132 such that the opening degree of electromagnetic valve 132 becomes the first opening degree when cooling is performed, and the opening degree of electromagnetic valve 132 is the first opening degree when cooling is not performed. The electromagnetic valve 132 is controlled so that the second opening is smaller than the opening.

  Further, in the present embodiment, ECU 400 controls electromagnetic valve 132 so that the first opening is fully opened when the refrigerant temperature detected by temperature sensor 134 is smaller than the threshold value, and the refrigerant temperature is When it is larger than the threshold value, the solenoid valve 132 is controlled so that the first opening degree is smaller than the full opening degree.

  When the amount of heat released from capacitor 40 is sufficiently large and the temperature of the refrigerant detected by temperature sensor 134 is surely below the threshold value, ECU 400 performs electromagnetic regardless of the temperature of the refrigerant when cooling is performed. The electromagnetic valve 132 may be controlled so that the opening degree of the valve 132 is fully opened. Further, ECU 400 may determine the opening degree of electromagnetic valve 132 based on the temperature of the refrigerant detected by temperature detection provided on the upstream side of electromagnetic valve 132.

  FIG. 2 shows a functional block diagram of ECU 400 of cooling device 10 according to the present embodiment. ECU 400 includes an operation determination unit 402, a liquid temperature determination unit 404, a first pressure reduction control unit 406, a compressor control unit 408, a second pressure reduction control unit 410, and a full open control unit 412.

  The operation determination unit 402 determines whether or not cooling is performed. The operation determination unit 402 is, for example, when a switch for cooling is turned on or when an automatic control mode for automatically adjusting the temperature of the vehicle interior to the set temperature is selected. And it determines with air_conditioning | cooling being performed when the temperature in a vehicle interior is higher than preset temperature. The operation determination unit 402 may turn on the operation determination flag when it is determined that cooling is performed, for example.

  The liquid temperature determination unit 404 determines whether or not the liquid temperature of the refrigerant detected by the temperature sensor 134 is greater than a threshold value. The threshold value is a threshold value for determining whether or not the liquid temperature of the refrigerant is in an appropriate range as a temperature for cooling the electric device. For example, the liquid temperature determination unit 404 may turn on the liquid temperature determination flag when the liquid temperature of the refrigerant detected by the temperature sensor 134 is higher than a threshold value.

  The first depressurization control unit 406 depressurizes the refrigerant so that the liquid temperature becomes equal to or lower than the threshold when cooling is performed and the liquid temperature of the refrigerant is higher than the threshold. For example, the first depressurization control unit 406 may depressurize the refrigerant on the downstream side of the electromagnetic valve 132 by controlling the opening of the electromagnetic valve 132 to be closed by a predetermined opening. Or you may make it the 1st pressure reduction control part 406 control the solenoid valve 132 so that only the opening degree determined according to the difference between the present liquid temperature of a refrigerant | coolant and a threshold value may be closed. Note that the first decompression control unit 406 may decompress the refrigerant when, for example, the operation determination flag is turned on and the liquid temperature determination flag is turned on. The first decompression control unit 406 is preferably used for cooling the electrical equipment in the cooling unit 120 in a state where the refrigerant after decompression maintains the liquid phase refrigerant.

  The compressor control unit 408 generates a control signal C1 so that the compressor 20 operates when cooling is not performed, and outputs the control signal C1 to the compressor 20. Alternatively, the compressor control unit 408 generates the control signal C1 and outputs the control signal C1 to the compressor 20 so as to maintain the operating state if the compressor 20 is in operation. For example, the compressor control unit 408 controls the compressor 20 so that the operation amount of the compressor 20 becomes a predetermined operation amount. For example, the compressor control unit 408 may operate the compressor 20 when the operation determination flag is turned off.

  Further, the compressor control unit 408 may lower the operation amount of the compressor 20 when the cooling is not performed than when the cooling is performed. If it does in this way, overcooling of an electric equipment can be prevented and an electric equipment can be cooled appropriately.

  The second depressurization control unit 410 controls the electromagnetic valve 132 so as to depressurize the liquid-phase refrigerant when cooling is not performed. The second pressure reduction control unit 410 determines the flow rate (pressure reduction amount) of the refrigerant in the electromagnetic valve 132 based on the temperature of the refrigerant detected by the temperature sensor 134, and the electromagnetic valve 132 so that the refrigerant flows at the determined flow rate. Adjust the opening. The second depressurization control unit 410 may depressurize the refrigerant so as to become a mist refrigerant in order to completely evaporate the refrigerant in the cooling passage 126, or depressurize so as to maintain the liquid phase refrigerant. In this manner, the evaporator 80 may be completely vaporized by reducing the pressure so that it becomes a mist refrigerant by the expansion valve 150.

  Note that the second pressure reduction control unit 410 may control the electromagnetic valve 132 so as to decompress the refrigerant when the operation determination flag is turned off, for example.

  The full-open control unit 412 controls the electromagnetic valve 132 so that the opening degree of the electromagnetic valve 132 is fully opened when cooling is performed and the liquid temperature of the refrigerant is equal to or lower than the threshold value. For example, the fully open control unit 412 controls the electromagnetic valve 132 so that the opening degree of the electromagnetic valve 132 is fully opened when the operation determination flag is turned on and the liquid temperature determination flag is turned off. May be.

  Preferably, the threshold value of the refrigerant liquid temperature for fully opening the solenoid valve 132 is smaller than the threshold value for executing the first pressure reduction control. If it does in this way, generation | occurrence | production of the control hunting of the solenoid valve 132 can be suppressed.

  In the present embodiment, the operation determination unit 402, the liquid temperature determination unit 404, the first pressure reduction control unit 406, the compressor control unit 408, the second pressure reduction control unit 410, and the full-open control unit 412 are all included. Although the description will be made assuming that the CPU of ECU 400 functions as software, which is realized by executing a program stored in the memory, it may be realized by hardware. Such a program is recorded on a storage medium and mounted on the vehicle.

  A control structure of a program executed by ECU 400 of cooling device 10 according to the present embodiment will be described with reference to FIG.

  In step (hereinafter, step is referred to as S) 100, ECU 400 determines whether or not cooling is on (that is, whether or not cooling is being performed). If cooling is on (YES in S100), the process proceeds to S102. If not (NO in S100), the process proceeds to S108.

  In S102, ECU 400 determines whether or not the coolant temperature is higher than a target value (threshold value). If the coolant temperature is higher than the target value (YES in S102), the process proceeds to S104. If not (NO in S102), the process proceeds to S106.

  In S104, ECU 400 executes the first pressure reduction control. That is, ECU 400 controls electromagnetic valve 132 so as to depressurize the refrigerant until the liquid temperature falls below the threshold value. In S106, ECU 400 controls electromagnetic valve 132 so that the opening degree of electromagnetic valve 132 is fully opened. In S108, ECU 400 executes the second pressure reduction control. That is, ECU 400 controls electromagnetic valve 132 so as to depressurize the refrigerant.

  An operation of cooling device 10 according to the present embodiment based on the above-described structure and flowchart will be described.

  For example, if cooling is performed (YES in S100) and the liquid temperature of the refrigerant is higher than the target value (YES in S102), the first pressure reduction control is executed (S104). By performing the first pressure reduction control, the refrigerant is depressurized so that the liquid temperature of the refrigerant becomes equal to or lower than the target value. When the liquid temperature of the refrigerant is equal to or lower than the target value (NO in S102), the electromagnetic valve 132 is controlled so that the opening degree of the electromagnetic valve 132 is fully opened (S106). When the opening degree of the electromagnetic valve 132 is fully opened, the liquid-phase refrigerant flowing from the capacitor 40 via the receiver 60 is supplied to the cooling unit 120.

  The liquid-phase refrigerant supplied to the cooling unit 120 flows through the expansion valve 150 after cooling the inverter 122 and the motor generator 124. The expansion phase 150 changes the liquid phase refrigerant into a mist refrigerant and supplies it to the evaporator 80. In the evaporator 80, the mist refrigerant absorbs the heat of the air in the vehicle interior by evaporation. The vapor-phase refrigerant evaporated by evaporation flows through the third connection passage 306 and then flows to the compressor 20. The gas-phase refrigerant compressed in the compressor 20 is liquefied again by releasing heat in the capacitor 40. In this way, the refrigerant circulates through the air conditioning refrigeration cycle system 12.

  On the other hand, when cooling is not performed (NO in S100), ECU 400 operates compressor 20 (S108), and then executes the second pressure reduction control (S110). That is, the solenoid valve 132 is controlled so as to reduce the pressure of the liquid phase refrigerant. In the cooling unit 120, the refrigerant whose temperature has decreased due to the reduced pressure flows through the cooling passage 126, so that the inverter 122 and the motor generator 124 are cooled.

  As described above, according to the cooling device according to the present embodiment, cooling is performed by providing a cooling unit for cooling the electrical equipment in series with the evaporator on the refrigerant path flowing from the condenser to the compressor. In some cases, the electrical equipment can be cooled using a liquid-phase refrigerant. Therefore, both the cooling and the cooling of the electric equipment can be performed with the same amount of operation of the compressor as that in the normal cooling when the cooling unit is not provided. In other words, it is not necessary to increase the power performance of the compressor in order to cool the electric device, and it is possible to avoid increasing the size of the compressor or providing a dedicated pump for cooling the electric device. Furthermore, when the cooling is not performed, the necessary cooling performance can be ensured by supplying the refrigerant so as to be vaporized in the cooling unit to cool the electric device. Therefore, it is possible to provide a cooling device that cools the electric device without deteriorating the compressor power requirement and the mountability to the vehicle.

<Second Embodiment>
Hereinafter, the cooling device according to the second embodiment will be described. Compared with the configuration of the cooling device 10 according to the first embodiment described above, the cooling device 10 according to the present embodiment has the point that the electromagnetic valve 132 is the first electromagnetic valve 132 and the temperature sensor 134 is the first. The difference is that the first temperature sensor 134 is used, and the second electromagnetic valve 136 and the second temperature sensor 138 are further included in place of the valve body 152 and the temperature sensing member 154. The other configuration is the same as the configuration of the cooling device 10 according to the first embodiment described above. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  As shown in FIG. 4, the cooling device 10 is provided in a second electromagnetic valve 136 provided in the second connection passage 304 upstream of the evaporator 80, and in a third connection passage 306 downstream of the evaporator 80, And a second temperature sensor 138 for detecting the temperature of the refrigerant in the three connection passages 306.

  The second temperature sensor 138 transmits a signal indicating the detected refrigerant temperature T2 to the ECU 400. The ECU 400 determines the flow rate (decompression amount) of the refrigerant based on the refrigerant temperature T2 received from the second temperature sensor 138. ECU 400 controls the opening degree of second electromagnetic valve 136 so that the determined refrigerant flow rate is realized.

  The opening degree of the second electromagnetic valve 136 is controlled by the ECU 400 between the fully open state and the fully closed state. In other words, the second electromagnetic valve 136 depressurizes the refrigerant by reducing the opening degree based on the control signal S1 received from the ECU 400, or allows the refrigerant to pass through without being depressurized by being fully opened.

  When the second electromagnetic valve 136 is in a fully open state, the resistance received from the passage when the refrigerant flows through the second electromagnetic valve 136 causes the refrigerant to flow through a portion other than the second electromagnetic valve 136 of the second connection passage 304. It is formed to be the same as the resistance received from the passage of time.

  Specifically, the second electromagnetic valve 136 is formed such that the internal shape when the second electromagnetic valve 136 is fully open matches the internal shape of the second connection passage 304 other than the second electromagnetic valve 136. Is done. For example, when the internal shape of the second connection passage 304 is a circle, the inner diameter when the second electromagnetic valve 136 is fully open is formed to be a circle that matches the inner diameter of the second connection passage 304. . If it does in this way, the change of the pressure of the refrigerant before and behind the 2nd electromagnetic valve 136 when the 2nd electromagnetic valve 136 is a full open state can be controlled.

  In the cooling device 10 according to the present embodiment having the above-described configuration, the ECU 400 causes the first electromagnetic so as to depressurize the refrigerant in order to vaporize the liquid-phase refrigerant in the cooling unit 120 when cooling is not performed. The second electromagnetic valve 136 is controlled such that the valve 132 is controlled and the opening degree of the second electromagnetic valve 136 is fully opened.

  FIG. 5 shows a functional block diagram of ECU 400 of cooling device 10 according to the present embodiment. The functional block diagram of ECU 400 shown in FIG. 5 is different from the functional block diagram of ECU 400 shown in FIG. 2 in that full open control unit 412 is first full open control unit 512, and second full open control unit 500. And the point which further includes the 3rd pressure reduction control part 502, and the operation | movement of the 2nd pressure reduction control part 410 differ. The other configuration is the same as that of ECU 400 according to the first embodiment described above. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here. The first full-open control unit 512 has the same function as the full-open control unit 412 shown in FIG. Therefore, detailed description thereof will not be repeated here.

  The second pressure reduction control unit 410 controls the first electromagnetic valve 132 so as to reduce the pressure of the liquid-phase refrigerant when cooling is not performed. The second pressure reduction control unit 410 determines the flow rate (pressure reduction amount) of the refrigerant in the first electromagnetic valve 132 based on the temperature of the refrigerant detected by the first temperature sensor 134 so that the refrigerant flows at the determined flow rate. The opening degree of the first electromagnetic valve 132 is adjusted. The second depressurization control unit 410 depressurizes the refrigerant so that it becomes a mist refrigerant so that it is completely vaporized in the cooling unit 120. Note that the second pressure reduction control unit 410 may control the first electromagnetic valve 132 so as to reduce the pressure of the refrigerant when the operation determination flag is turned off, for example.

  The second fully open control unit 500 controls the second electromagnetic valve 136 so that the opening degree of the second electromagnetic valve 136 is fully opened when the operation determination unit 402 determines that the cooling is not performed. Note that the second fully open control unit 500 may control the second solenoid valve 136 so that the opening degree of the second solenoid valve 136 is fully opened when the operation determination flag is OFF, for example.

  The third decompression control unit 502 converts the liquid-phase refrigerant flowing through the second connection passage 304 into a mist refrigerant so that the evaporator 80 completely vaporizes when it is determined that the cooling is performed in the operation determination unit 402. The refrigerant is depressurized so that The third pressure reduction control unit 502 determines the flow rate (pressure reduction amount) of the refrigerant in the second electromagnetic valve 136 based on the refrigerant temperature detected by the second temperature sensor 138 so that the refrigerant flows at the determined flow rate. The opening degree of the second electromagnetic valve 136 is adjusted. For example, when the operation determination flag is on, the third pressure reduction control unit 502 reduces the refrigerant so that the liquid-phase refrigerant flowing through the second connection passage 304 becomes a mist refrigerant. May be controlled.

  With reference to FIG. 6, a control structure of a program executed by ECU 400 of cooling device 10 according to the present embodiment will be described.

  In the flowchart shown in FIG. 6, the same steps as those in the flowchart shown in FIG. 3 are given the same step numbers. The processing for them is the same. Therefore, detailed description thereof will not be repeated here.

  When it is determined that the cooling is on (YES in S100), ECU 400 executes the third pressure reduction control in S200. That is, the ECU 400 controls the opening of the second electromagnetic valve 136 so that the refrigerant is decompressed in order to completely vaporize the liquid-phase refrigerant flowing through the second connection passage 304 in the evaporator 80, and the process proceeds to S102. return.

  If it is determined that the coolant temperature at the outlet side of cooling passage 126 is equal to or lower than the target value (NO in S102), ECU 400 determines that the opening degree of first electromagnetic valve 132 is fully opened in S206. 1 The electromagnetic valve 132 is controlled.

  After executing the second pressure reduction control (S108), in S210, the ECU 400 executes the second fully open control. That is, ECU 400 controls second electromagnetic valve 136 so that the opening degree of second electromagnetic valve 136 is fully opened. The execution order of the second pressure reduction control, the second fully open control, and the compressor operation is not particularly limited to the order shown in the flowchart of FIG. ECU 400 may execute the second pressure reduction control, the second fully open control, and the compressor operation in parallel.

  An operation of cooling device 10 according to the present embodiment based on the above-described structure and flowchart will be described.

  For example, when cooling is performed (YES in S100), since the third pressure reduction control is executed, the liquid-phase refrigerant flowing through the second connection passage 304 using the second electromagnetic valve 136 is completely removed in the evaporator 80. In order to evaporate, the refrigerant is depressurized to become a mist refrigerant (S200).

  When the liquid temperature of the refrigerant flowing through second connection passage 304 is higher than the target value (YES in S102), the first pressure reduction control is executed (S104). By performing the first pressure reduction control, the refrigerant is depressurized until the liquid temperature of the refrigerant becomes equal to or lower than the target value. When the liquid temperature of the refrigerant is equal to or lower than the target value (NO in S102), the liquid-phase refrigerant flowing from the capacitor 40 via the receiver 60 is cooled by opening the first electromagnetic valve 132 fully. To be supplied to the unit 120.

  The liquid phase refrigerant supplied to the cooling unit 120 cools the inverter 122 and the motor generator 124 and then flows to the second electromagnetic valve 136. The refrigerant that has flowed through the second electromagnetic valve 136 is reduced in pressure by the execution of the third pressure reduction control, so that it changes into a mist refrigerant and is supplied to the evaporator 80. In the evaporator 80, the mist refrigerant evaporates and absorbs the heat of the air in the vehicle interior. Therefore, the vapor phase refrigerant that has evaporated flows through the third connection passage 306 to the compressor 20. The gas-phase refrigerant compressed in the compressor 20 is liquefied again by releasing heat in the capacitor 40. In this way, the refrigerant circulates through the air conditioning refrigeration cycle system 12.

  On the other hand, when cooling is not performed (NO in S100), ECU 400 executes the second pressure reduction control (S110) after compressor 20 is operated (S108). That is, the first electromagnetic valve 132 is controlled so that the liquid-phase refrigerant is decompressed. In cooling unit 120, inverter 122 and motor generator 124 are cooled by the decompressed refrigerant. The refrigerant is completely vaporized in the cooling unit 120 and absorbs the heat of the electric device to cool the electric device. The gas-phase refrigerant vaporized in the cooling unit 120 flows to the second electromagnetic valve 136 via the second connection passage 304.

  The second electromagnetic valve 136 is fully opened by executing the second fully open control (S210). The gas-phase refrigerant flows to the compressor 20 via the second electromagnetic valve 136, the evaporator 80, and the third connection passage 306.

  As described above, the cooling device according to the present embodiment has the same operational effects as the cooling device according to the first embodiment described above.

<Third Embodiment>
Hereinafter, a cooling device according to a third embodiment will be described. The cooling device 10 according to the present embodiment is different from the configuration of the cooling device 10 according to the first embodiment described above in that it further includes a check valve 140 and a device temperature sensor 142. The other configuration is the same as the configuration of the cooling device 10 according to the first embodiment described above. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  As shown in FIG. 7, the cooling device 10 further includes a check valve 140 and a device temperature sensor 142.

  The check valve 140 is provided in the fourth connection passage 308 that connects the compressor 20 and the condenser 40. The check valve 140 allows the refrigerant to flow from the compressor 20 to the condenser 40 and blocks the refrigerant from the condenser 40 to the compressor 20. The check valve 140 may be an electromagnetic valve that blocks the flow of the refrigerant when the compressor 20 is stopped and allows the flow of the refrigerant when the compressor 20 is activated.

  The device temperature sensor 142 detects the temperature T3 of the electrical device. Device temperature sensor 142 may be provided in each of inverter 122 and motor generator 124, or may be provided in any one of inverter 122 and motor generator 124. Preferably, the inverter 122 and the motor generator 124 are provided on one of the inverters 122 and the motor generator 124 that has a large amount of heat generation, one that tends to have a high temperature, or one that has a large temperature increase. In this way, it is possible to determine with high accuracy whether or not there is a cooling request for the electrical equipment. Device temperature sensor 142 transmits a signal indicating temperature T3 of the electric device to ECU 400. Alternatively, the ECU 400 may estimate the temperature of the electric device based on the refrigerant temperature T1 detected by the temperature sensor 134.

  In the cooling device 10 according to the present embodiment having the above-described configuration, the opening degree of the electromagnetic valve 132 is fully closed when the ECU 400 is not cooled and there is no request for cooling the electrical equipment. The electromagnetic valve 132 is controlled so that

  In the present embodiment, ECU 400 determines that there is no request for cooling of the electric device when temperature T3 of the electric device detected by device temperature sensor 142 is lower than the threshold value. Further, ECU 400 may determine that there is a request for cooling of the electrical device when temperature T3 of the electrical device detected by device temperature sensor 142 is equal to or higher than the threshold value, or has been detected. When the temperature T3 of the electric device is equal to or higher than a value obtained by adding a predetermined value to the threshold value, it may be determined that there is a cooling request for the electric device.

  FIG. 8 shows a functional block diagram of ECU 400 of cooling device 10 according to the present embodiment. 8 is different from the functional block diagram of ECU 400 shown in FIG. 2 in that it further includes a cooling request determination unit 600 and a fully-closed control unit 602. The other configuration is the same as that of ECU 400 according to the first embodiment described above. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  The cooling request determination unit 600 determines whether or not there is a cooling request for the electrical device when the operation determination unit 402 determines that the cooling is not performed. Specifically, the cooling request determination unit 600 determines that there is a cooling request for the electric device when the temperature T3 of the electric device detected by the device temperature sensor 142 is equal to or higher than a threshold value. The cooling request determination unit 600 determines, for example, whether or not there is a cooling request for the electric device when the operation determination flag is off, and determines that there is a cooling request for the electric device. The flag may be turned on.

  The fully-closed control unit 602 controls the electromagnetic valve 132 so that the operation of the compressor 20 is stopped and the opening degree of the electromagnetic valve 132 is fully closed when there is no request for cooling the electrical equipment. In addition, when the compressor 20 is in a stopped state, the fully-closed control unit 602 controls the electromagnetic valve 132 so that the stopped state is maintained and the opening degree of the electromagnetic valve 132 is fully closed. Note that the fully-closed control unit 602 stops the operation of the compressor 20 and the degree of opening of the electromagnetic valve 132 is fully closed when, for example, the operation determination flag is turned off and the cooling request determination flag is turned off. The electromagnetic valve 132 may be controlled so that

  With reference to FIG. 9, a control structure of a program executed by ECU 400 of cooling device 10 according to the present embodiment will be described.

  In the flowchart shown in FIG. 9, the same steps as those in the flowchart shown in FIG. 3 are given the same step numbers. The processing for them is the same. Therefore, detailed description thereof will not be repeated here.

  When it is determined that the cooling is off (YES in S100), ECU 400 determines in S300 whether there is a request for cooling the electrical device. If there is a cooling request for the electrical device (YES in S30), the process proceeds to S108. If not (NO in S300), the process proceeds to S302.

  In S302, ECU 400 controls electromagnetic valve 132 so that the opening degree of electromagnetic valve 132 is fully closed. In S304, ECU 400 stops the operation of compressor 20, or maintains the operation stop state of compressor 20.

  An operation of cooling device 10 according to the present embodiment based on the above-described structure and flowchart will be described.

  For example, if cooling is performed (YES in S100) and the liquid temperature of the refrigerant is higher than the target value (YES in S102), the first pressure reduction control is executed (S104). By performing the first pressure reduction control, the refrigerant is depressurized so that the liquid temperature of the refrigerant becomes equal to or lower than the target value. When the liquid temperature of the refrigerant is equal to or lower than the target value (NO in S102), the electromagnetic valve 132 is controlled so that the opening degree of the electromagnetic valve 132 is fully opened (S106). When the opening degree of the electromagnetic valve 132 is fully opened, the liquid-phase refrigerant flowing from the capacitor 40 via the receiver 60 is supplied to the cooling unit 120.

  The liquid-phase refrigerant supplied to the cooling unit 120 flows through the expansion valve 150 after cooling the inverter 122 and the motor generator 124. The expansion phase 150 changes the liquid phase refrigerant into a mist refrigerant and supplies it to the evaporator 80. In the evaporator 80, the mist refrigerant absorbs the heat of the air in the vehicle interior by evaporation. The vapor-phase refrigerant evaporated by evaporation passes through the third connection passage 306 and flows to the compressor 20. The gas-phase refrigerant compressed in the compressor 20 is liquefied again by releasing heat in the capacitor 40. In this way, the refrigerant circulates through the air conditioning refrigeration cycle system 12.

  On the other hand, if cooling is not performed (NO in S100) and ECU 400 determines that there is a cooling request due to temperature T3 of the electrical equipment being higher than the threshold value (YES in S300), ECU 400 After the compressor 20 is operated (S108), the second pressure reduction control is executed (S110). That is, the solenoid valve 132 is controlled so as to reduce the pressure of the liquid phase refrigerant. In the cooling unit 120, the refrigerant whose temperature has decreased due to the reduced pressure flows through the cooling passage 126, so that the inverter 122 and the motor generator 124 are cooled.

  If cooling is not performed (NO in S100), and it is determined that there is no cooling request because temperature T3 of the electrical device is equal to or lower than the threshold value (NO in S300), ECU 400 The solenoid valve 132 is controlled so that the opening degree of the solenoid valve 132 is fully closed (S302), and is stopped when the compressor 20 is operating, and is stopped when the operation of the compressor 20 is stopped. Is maintained (S304).

  Since the refrigerant flow between the check valve 140 including the capacitor 40 and the electromagnetic valve 132 is blocked, the refrigerant pressure in this section is maintained. Therefore, it is possible to hold the work done until the compressor 20 stops while the compressor 20 is stopped.

  As described above, according to the cooling device according to the present embodiment, in addition to the operational effects of the cooling device according to the first embodiment described above, cooling is not performed, and the electric device By stopping the operation of the compressor 20 when there is no cooling request, it is possible to hold the work until the compressor 20 is stopped by the check valve and the electromagnetic valve. Therefore, the work held when the compressor 20 is activated again can be used effectively.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 10 Cooling device, 12 Air-conditioning refrigerating cycle system, 20 Compressor, 40 Condenser, 60 Receiver, 80 Evaporator, 132,136 Solenoid valve, 134,138 Temperature sensor, 120 Cooling part, 122 Inverter, 124 Motor generator, 126 Cooling path, 134 Temperature sensor, 140 Check valve, 142 Equipment temperature sensor, 150 Expansion valve, 152 Valve body, 154 Temperature sensitive member, 302, 304, 306, 308 Connection path, 402 Operation determination unit, 404 Liquid temperature determination unit, 406 1 decompression control unit, 408 compressor control unit, 410 second decompression control unit, 412 full open control unit, 500 first full open control unit, 502 third decompression control unit, 512 second full open control unit, 600 cooling request determination unit, 602 Fully closed control unit.

Claims (6)

A cooling device for cooling electrical equipment mounted on a vehicle,
A compressor for circulating the refrigerant;
A condenser for condensing the refrigerant;
An evaporator for cooling the interior of the vehicle using the refrigerant;
A cooling unit provided in series with the evaporator on a path of the refrigerant flowing from the condenser to the compressor, and for cooling the electric device using the refrigerant ;
A detection unit for detecting the refrigerant temperature in the path,
The cooling unit includes an electromagnetic valve for decompressing the refrigerant supplied to the cooling unit,
The cooling device controls the electromagnetic valve so that the opening degree of the electromagnetic valve becomes the first opening degree when the cooling is performed, and the opening degree of the electromagnetic valve is set when the cooling is not performed. A control unit for controlling the solenoid valve to have a second opening;
The first opening is larger than the second opening,
The controller controls the solenoid valve so that the first opening is fully opened when the refrigerant temperature is smaller than a threshold value, and when the refrigerant temperature is larger than the threshold value, A cooling device that controls the solenoid valve such that the first opening is smaller than the fully open position . The first cross-sectional shape in the case where the opening of the electromagnetic valve is fully opened is formed so that the resistance during circulation of the refrigerant does not become larger than the second cross-sectional shape of the passage forming the path. 2. The cooling device according to 1 . The solenoid valve interrupts the flow of the refrigerant in the path when the opening of the solenoid valve is fully closed;
The cooling device further includes a check valve for allowing the refrigerant to flow from the compressor side to the condenser side and blocking the refrigerant flow from the capacitor side to the compressor side,
The control unit controls the electromagnetic valve so that the opening degree of the electromagnetic valve is fully closed when the cooling is not performed and when there is no cooling request for the electric device. Item 3. The cooling device according to Item 1 or 2 . The cooling device according to claim 3 , wherein the control unit determines that there is no cooling request for the electrical device when the temperature of the electrical device is lower than a threshold value. The cooling device according to any one of claims 1 to 4 , wherein the control unit operates the compressor when the electric device is cooled by the cooling unit even when the cooling is not performed. . The cooling unit is provided between the capacitor and the evaporator,
The cooling device according to any one of claims 1 to 5 , wherein a valve is provided between the evaporator and the cooling unit to supply the mist-like refrigerant to the evaporator when the cooling is performed. .

Images