Temperature control system for a vehicle and temperature control method

Abstract

One objective is to ensure heat capacity even in a situation where it is difficult to secure a heat source due to low outside air temperature. A temperature control system for a vehicle includes a refrigerant circuit and a heat medium circuit. The heat medium circuit includes a high-pressure side heat exchanger, a low-pressure side heat exchanger, a pump, an outdoor heat exchanger, a temperature control device, and an outdoor heat exchanger bypass passage. In the temperature control system, a power heat source mode is provided, which is a mode in which a heat medium flowing out of the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device and further flows into the high-pressure side heat exchanger via the outdoor heat exchanger bypass passage, and power of a compressor and power of the pump are used as a heat source.A controller is configured to change a speed of the pump to at least a first speed set for the pump in another operating mode and a second speed higher than the first speed, and set the second speed for the pump in the power heat source mode.

Description

Technical area

[0001] The present disclosure relates to a temperature control system mounted in a vehicle and a temperature control method using the same. State of the art

[0002] In a vehicle such as an electric vehicle or a so-called hybrid vehicle that derives driving power for vehicle travel from an engine and an electric motor, even in a case where a heat source is likely to be insufficient, in addition to the air-conditioning functions required for the vehicle, such as cooling, heating, dehumidification, and ventilation, heat management of an in-vehicle device such as a battery or heat utilization is required. In response to such a demand, in addition to a heat pump system, the related art uses multiple systems, such as a system including a radiator that cools a battery and a heater that heats a battery, or a system in which water heated by thermal radiation from a radiator is transported to a temperature control destination by a pump.

[0003] As a thermal management system for a vehicle capable of integrating air conditioning and thermal management for one device, a system including a primary circuit in which a refrigerant circulates in accordance with a refrigeration cycle and a secondary circuit in which a heat medium (water or the like) exchanging heat with the refrigerant in the primary circuit is transported to a device in the vehicle by a pump is proposed (for example, PTL 1).

[0004] The thermal management system disclosed in PTL 1 includes a first thermal medium circuit in which an evaporator of a refrigerant circuit and a thermal medium-outside air heat exchanger are arranged, and a second thermal medium circuit in which a condenser of the refrigerant circuit and a heater core of a cabin air conditioning unit are arranged. The first thermal medium circuit and the second thermal medium circuit are switched by switching a flow channel by first switching means and second switching means to a non-coupling state (non-coupling mode) and a coupling state (coupling mode) at an assumed low outside air temperature.

[0005] In the non-coupling mode, a heat pump operation of drawing heat from outside air into a heat medium of the second heat medium circuit is performed. In the coupling mode, a heat medium flowing out of the condenser comes into contact with a heat medium flowing out of the evaporator without allowing it to flow into the heat medium-outside air heat exchanger, and the heat medium is forced to flow into the evaporator and the condenser in parallel. At this time, the first heat medium circuit and the second heat medium circuit are coupled to each other via the evaporator and the condenser. Citation listPatent literature

[0006] [PTL 1] Japanese Patent No. 6083304 Summary of the inventionTechnical problem

[0007] During the coupling mode in PTL 1, the heat medium flowing out of the evaporator and the heat medium flowing out of the condenser are mixed to have an intermediate temperature between the temperatures of the respective heat media before mixing, and the heat media flow into the evaporator and the condenser. Therefore, compared to the non-coupling mode, it takes a long time to increase the temperature of the heat medium flowing out of the condenser. In addition, since the flow rate of the heat medium flowing into a cabin heat exchanger is reduced, there is room for improving the heat capacity.

[0008] An object of the present disclosure is to provide a vehicle temperature control system and a temperature control method capable of ensuring a heat capacity even in a situation where it is difficult to ensure a heat source due to a low outside air temperature. Solution to the problem

[0009] According to the present disclosure, there is provided a temperature control system comprising: a refrigerant circuit configured to include a compressor, a high-pressure side heat exchanger, a pressure reducing unit, and a low-pressure side heat exchanger, and circulates a refrigerant in accordance with a refrigeration cycle; and a heat medium circuit configured to circulate a heat medium that exchanges heat with the refrigerant.

[0010] The heat medium circuit includes the high-pressure side heat exchanger that performs heat exchange between the refrigerant and the heat medium, the low-pressure side heat exchanger that performs heat exchange between the refrigerant and the heat medium, a pump configured to pump the heat medium, an outdoor heat exchanger that performs heat exchange between outside air and the heat medium, a temperature control device that corresponds to a temperature control target heated or cooled by the heat medium or is used to heat or cool the temperature control target, and an outdoor heat exchanger bypass channel that guides the heat medium to bypass the outdoor heat exchanger.

[0011] The temperature control system further includes: a power heat source mode, which is a mode in which the heat medium flowing out of the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device and further flows into the high-pressure side heat exchanger via the outdoor heat exchanger bypass channel, and power of the compressor and power of the pump are used as a heat source; and a control device configured to variably adjust a rotation speed of the pump.

[0012] The controller is configured to change the speed of the pump to at least a first speed set for the pump in another operating mode and a second speed higher than the first speed, and set the second speed for the pump in the power heat source mode.

[0013] Furthermore, the present disclosure can also be applied to a temperature control method. Advantageous effects of the invention

[0014] According to the present disclosure, it is possible to provide a temperature control system for a vehicle in which a heat source thereof is likely to be insufficient, wherein even in a case where heat absorption from outside air is insufficient due to a condition where an outside air temperature is significantly lower than 0°C, the insufficient heat source can be compensated and a heat capacity can be ensured by increasing power of a pump in a power heat source mode.

[0015] Since a high-pressure side heat exchanger and a low-pressure side heat exchanger are connected in series during the power heat source mode, the temperature of a heat medium flowing out of the high-pressure side heat exchanger can be increased more rapidly than in a case where the heat medium flows in parallel between the high-pressure side heat exchanger and the low-pressure side heat exchanger. Furthermore, since the amount of heat medium circulating in a temperature control device is large, the amount of heat exchanged between the heat medium and a temperature control target is large. Brief description of the drawings Fig. 1 is a circuit diagram illustrating a temperature control system for vehicle according to an embodiment of the present disclosure (heat pump mode). Fig. 2 is a diagram showing an operating state in a heating mode of the Fig. 1 system. Fig. 3 is a block diagram illustrating a hardware configuration of a control device. Fig. Figure 4 is a schematic view of a pH line graph at a low outdoor air temperature. Fig. 5 is a graph showing a relationship (characteristics of low-pressure compressor capacity) between a low pressure and compressor capacity of a refrigerant cycle in the heating mode. Fig. 6 is a circuit diagram illustrating a temperature control system for vehicle according to a fifth modification example of the present disclosure (heating mode at start-up). Description of embodiments

[0016] Embodiments of the present disclosure will be described below with reference to the accompanying drawings. [Embodiment]

[0017] One in Fig. The vehicle temperature control system 1 shown in FIG. 1 is mounted, for example, in a vehicle (not shown), such as an electric vehicle that does not include an engine and receives driving power for vehicle travel from an electric motor, or a so-called hybrid vehicle that receives driving power for vehicle travel from an engine and an electric motor. The temperature control system 1 is responsible for heat management, waste heat recovery, and the like of in-vehicle devices such as a battery device (power supply device), a motor for travel, and an electronic heat generation device mounted in a vehicle, in addition to air conditioning functions such as heating, cooling, dehumidification, and ventilation of a cabin 8 in which an occupant is on board.Air conditioning for a suitable temperature or humidity or management for a suitable temperature of the device in the vehicle is called “thermal management”.

[0018] Energy stored in an in-vehicle battery device is supplied to the temperature control system 1 and an electric motor or an electronic device provided in the in-vehicle battery device other than the temperature control system 1. The in-vehicle battery device is charged by an external power supply at a time of vehicle stop. [Overall configuration]

[0019] The temperature control system 1 includes a refrigerant circuit 10 configured to circulate a refrigerant, a heat medium circuit 20 configured to circulate a heat medium that exchanges heat with the refrigerant, and a control device 5 that sets the temperature control system 1 to a predetermined operation mode and controls an operation state of the temperature control system 1 in accordance with the operation mode.

[0020] In addition, the temperature control system 1 includes, for example, a sensor such as an outside air temperature sensor 61 that detects an outside air temperature, a temperature sensor 62 that detects a temperature of conditioned air blown into the cabin 8, a low-pressure pressure sensor 63 that detects a low pressure pL of the refrigerant circuit 10, a high-pressure pressure sensor 64 that detects a high pressure pH of the refrigerant circuit 10, and a heat medium temperature sensor 65 that detects a temperature of the heat medium.

[0021] The temperature control system 1 has several operating modes that are selected by an occupant or the control device 5. The temperature control system 1 is configured to provide power from pumps 21 and 22 operating in a heating mode HT ( Fig. 2) pumping the heat medium is used as a heat source. In the present embodiment, in addition to the heating mode HT, a heat pump mode HP ( Fig. 1) as an operation mode of the temperature control system 1 is described as an example. The heating mode HT is suitable for a case where an outside air temperature is lower compared to the heat pump mode HP. [Refrigerant circuit configuration]

[0022] As shown in a configuration example in Fig. 1, the refrigerant circuit 10 includes a compressor 11, a condenser 12, an expansion valve 13, and an evaporator 14. A refrigerant is circulated in the refrigerant circuit 10 in accordance with a refrigeration cycle.

[0023] As the refrigerant sealed in the refrigerant cycle 10, a known suitable single refrigerant or mixed refrigerant can be used. For example, as the refrigerant according to the present embodiment, a hydrofluorocarbon (HFC) refrigerant such as R410A or R32, a hydrofluoroolefin (HFO) refrigerant such as R1234ze or R1234yf, or a hydrocarbon (HC) refrigerant such as propane or isobutane can be used. In particular, it is preferable to use R1234yf as the refrigerant of the present embodiment.

[0024] In a case where the fluorine-based refrigerant or the hydrocarbon-based refrigerant described above is used, a subcritical refrigeration cycle is configured in which a refrigerant pressure on a high-pressure side does not exceed a critical pressure of the refrigerant.

[0025] In a case where carbon dioxide (CO2) is used as the refrigerant, a transcritical refrigeration cycle is configured in which the refrigerant pressure on the high-pressure side exceeds the critical pressure of the refrigerant. Even in this case, since an effect in which the refrigerant releases heat through a high-pressure side heat exchanger in the same manner as the condenser 12 according to the present embodiment and the refrigerant absorbs heat through a low-pressure side heat exchanger in the same manner as the evaporator 14 according to the present embodiment can be obtained, the refrigerant constituting the transcritical refrigeration cycle, such as carbon dioxide refrigerant, can be used in the refrigerant cycle 10.

[0026] The compressor 11 corresponds to an electric compressor equipped with a motor driven by power supplied from a battery device (not shown). The compressor 11 adiabatically compresses the refrigerant sucked into a housing (not shown) with a compression mechanism and discharges the refrigerant.

[0027] In the HT heating mode, the power of the compressor 11 is a heat source. The compressor 11 is an electric compressor, and in this case, a motor and a main body portion (compressor main body) of the compressor constitute the heat source. That is, when power is supplied to the motor, heat is generated due to copper loss, iron loss, and mechanical loss. The compressor main body can be a heat source by generating heat based on the theory of adiabatic compression and the Boyle-Charles law. In the compressor 11, heat is given to the refrigerant flowing through the compressor main body.

[0028] The condenser 12 performs heat exchange with a refrigerant gas discharged from the compressor 11 as a heat medium.

[0029] The expansion valve 13 (pressure reducing unit) reduces the pressure of the refrigerant flowing out of the condenser 12 to adiabatically expand the refrigerant. As the expansion valve 13, a temperature-type expansion valve can be used in addition to an electronic expansion valve capable of controlling an opening degree based on a command from the control device 5. Alternatively, a capillary tube can be used instead of the expansion valve 13.

[0030] The evaporator 14 performs heat exchange with the refrigerant flowing out of the expansion valve 13 as a heat medium. The refrigerant evaporated by the evaporator 14 is sucked in by the compressor 11.

[0031] An accumulator (gas-liquid separator) (not shown) may be provided between the evaporator 14 and the compressor 11.

[0032] The condenser 12 is provided with a relatively high refrigerant pressure (high pressure pH), and the evaporator 14 is provided with a relatively low refrigerant pressure (low pressure pL). The refrigerant is circulated through the refrigerant circuit 10 based on a pressure difference between the high pressure pH and the low pressure pL.

[0033] In Fig. 1, a flow of refrigerant on a low-pressure side is indicated by a thick solid line, and a flow of refrigerant on a high-pressure side is indicated by a thick dashed line. The same is shown on Fig. 2 applied. [Configuration of heat medium circuit]

[0034] The heat medium circuit 20 is configured to circulate a heat medium capable of exchanging heat with a refrigerant via the condenser 12 and the evaporator 14. The heat medium is used to cool or heat at least one or more temperature control targets. One of the temperature control targets in the present embodiment corresponds to the air in the cabin 8.

[0035] The heat medium sealed in the heat medium circuit 20 is a liquid, such as water or brine, which is maintained in a liquid phase state and circulated in the heat medium circuit 20. Examples of the brine include a liquid mixture of water and propylene glycol or a liquid mixture of water and ethylene glycol.

[0036] As shown in a configuration example in Fig. 1, the heat medium circuit 20 includes the condenser 12, the evaporator 14, the first pump 21 and the second pump 22, an outdoor heat exchanger 23, an outdoor heat exchanger bypass passage 24, a cabin heat exchanger 25, and a first switching valve 31, a second switching valve 32, and a third switching valve 33 as a plurality of flow passage switching valves.

[0037] The first pump 21 and the second pump 22 also include a motor as a power source and a pump main body as a booster unit. The first pump 21 and the second pump 22 each generate heat through the same action as the compressor 11 and thus can be a heat source. The first pump 21 and the second pump 22 heat a heat medium passing through the first pump 21 and the second pump 22.

[0038] In the present embodiment, the first switching valve 31 and the second switching valve 32 are four-way valves, and the third switching valve 33 corresponds to a three-way valve. Fig. In the heat pump mode HP shown in Figure 1, both a heat medium flowing out of the condenser 12 and a heat medium flowing out of the evaporator 14 are circulated in the first switching valve 31.

[0039] The heat medium circuit 20 includes a reserve tank 15 as a mechanism for maintaining a suction side of the pumps 21 and 22 at atmospheric pressure. According to the reserve tank 15, even if the pressure of the heat medium increases due to volume expansion of the heat medium caused by a temperature rise, the suction sides of the pumps 21 and 22 are maintained below atmospheric pressure. Therefore, the heat medium can be stably pumped by the pumps 21 and 22.

[0040] Although a separate reserve tank may be provided on the suction side of each of the pumps 21 and 22, only one reserve tank 15 communicating with one pipe 401 and one pipe 402 may be provided. It is preferable that an on / off valve 17 connecting only one of the pipes 401 and 402 to the reserve tank 15 be provided in a communication channel 16 connecting the pipes 401 and 402 to the reserve tank 15. By closing the on / off valve 17 when a series connection CC to be described below is used, it is possible to prevent the heat medium from moving through the communication channel 16 due to a pressure difference.

[0041] It is preferable that the heat medium circuit 20 includes a condenser bypass passage 12A that guides the heat medium to bypass the condenser 12 and a condenser flow control valve 12V.

[0042] The condenser flow control valve 12V controls a flow rate ratio of the heat medium of the condenser 12 and the condenser bypass channel 12A based on a control command generated by the control device 5.

[0043] In the Fig. 1, the total amount of heat medium flowing from the first switching valve 31 to the condenser 12 flows into the condenser 12 without flowing into the condenser bypass passage 12A due to the current control by the condenser flow control valve 12V.

[0044] Furthermore, it is preferable that the heat medium circuit 20 includes an evaporator bypass passage 14A that guides the heat medium to bypass the evaporator 14, and an evaporator flow control valve 14V configured to control a flow rate ratio of the evaporator 14 and the evaporator bypass passage 14A.

[0045] The evaporator flow control valve 14V controls a flow rate ratio of the heat medium of the evaporator 14 and the evaporator bypass passage 14A based on a control command generated by the control device 5.

[0046] In the Fig. 1, the total amount of heat medium flowing from the first switching valve 31 to the evaporator 14 flows into the evaporator 14 without flowing into the evaporator bypass passage 14A due to the flow control by the evaporator flow control valve 14V.

[0047] The condenser flow control valve 12V as a three-way valve according to the present embodiment can be replaced by two two-way valves capable of performing flow control, or by a single two-way valve capable of performing flow control. For example, one two-way valve can be arranged in the condenser bypass channel 12A, and the other two-way valve can be arranged in a pipe between the condenser flow control valve 12V and the condenser 12. Alternatively, the single two-way valve can be arranged in the condenser bypass channel 12A and one of the pipes.

[0048] The evaporator flow control valve 14V is as described above and can be replaced by two two-way valves capable of performing flow control or by a single two-way valve capable of performing flow control.

[0049] Both the first pump 21 and the second pump 22 are electric pumps driven by a motor (not shown). The first pump 21 pumps the heat medium by sucking in and discharging the heat medium flowing out of the evaporator 14. The second pump 22 pumps the heat medium by sucking in and discharging the heat medium flowing out of the condenser 12.

[0050] As the pumps 21 and 22, a known centrifugal pump or a volumetric pump can be suitably used.

[0051] At least one of the first pump 21 and the second pump 22 is configured to variably control a rotational speed N of a heat medium pumping mechanism by a drive circuit unit that applies a drive current to the motor. In the present embodiment, both the first pump 21 and the second pump 22 are configured to variably control the rotational speed N.

[0052] A position of each of the first pump 21 and the second pump 22 is not limited to the Fig. 1 and can be appropriately determined within a range in which the heat medium can be pumped by at least one of the first pump 21 and the second pump 22 taking into account the passage of the heat medium in each operation mode.

[0053] The outdoor heat exchanger 23 performs heat exchange between outside air on an exterior side of the cabin 8 and the heat medium. The outdoor heat exchanger 23 corresponds, for example, to a radiator arranged near an air intake of the vehicle. The outside air supplied to the outdoor heat exchanger 23 by vehicle travel and operation of an outdoor fan 23A releases or absorbs heat based on a temperature difference between the outside air and the heat medium.

[0054] The outdoor heat exchanger bypass channel 24 guides the heat medium so that it bypasses the outdoor heat exchanger 23.

[0055] The cabin heat exchanger 25 performs heat exchange between air supplied by a cabin blower 25A and the heat medium to supply conditioned air to the cabin 8. The cabin blower 25A is driven by a motor and blows air (inside air) in the cabin 8, outside air, or a mixed gas of the inside air and outside air to the cabin heat exchanger 25. It is preferable that the cabin blower 25A be configured to variably control a rotation speed.

[0056] An HVAC (heating, ventilation, and air conditioning) unit U includes the cabin heat exchanger 25, the cabin fan 25A, and a duct (not shown) through which air conveyed by the cabin fan 25A flows.

[0057] A flow of the heat medium is switched by at least one of the first to third switching valves 31, 32, and 33, so that the heat medium circuit 20 is configured to have a low-pressure side circuit C1 and a high-pressure side circuit C2 in parallel ( Fig. 1) and the series connection CC ( Fig. 2) is set.

[0058] The high-pressure side circuit C2 of the heat medium flowing out of the condenser 12 and flowing back to the condenser 12 and the low-pressure side circuit C1 flowing out of the evaporator 14 and flowing back to the evaporator 14 are separated from each other. Hereinafter, the low-pressure side circuit C1 and the high-pressure side circuit C2 may be referred to as parallel circuits C1 and C2.

[0059] A heat medium of the high-pressure side circuit C2 containing the condenser 12 and a heat medium of the low-pressure side circuit C1 containing the evaporator 14 are not mixed with each other.

[0060] In Fig. 1, which represents the parallel circuits C1 and C2, the flow of a relatively low-temperature heat medium (low-temperature heat medium) circulating in the low-pressure side circuit C1 is indicated by a solid line, and the flow of a relatively high-temperature heat medium (high-temperature heat medium) circulating in the high-pressure side circuit C2 is indicated by a one-dot chain line. A channel through which neither the low-temperature heat medium nor the high-temperature heat medium is pumped is indicated by a dashed line.

[0061] On the other hand, the series circuit CC corresponds to a continuous circuit containing the evaporator 14 and the condenser 12 arranged in series. In a case where the series circuit CC is arranged, for example, as in Fig. 2, the heat medium flowing out of the condenser 12 flows into the evaporator 14 and flows further into the condenser 12.

[0062] Also in Fig. 2, which represents the series circuit CC, a flow of a heat medium with a relatively low temperature is indicated by a solid line, and a flow of a heat medium with a relatively high temperature is indicated by a one-dot chain line. With reference to Fig. In FIG. 2, unlike the case where the parallel connections C1 and C2 are set, the flow of the heat medium from the evaporator 14 to the outflow and flow into the condenser 12 is indicated by a solid line, and the flow of the heat medium from the condenser 12 to the outflow and flow into the evaporator 14 is indicated by a one-dot chain line. This represents that when the heat medium flows into the evaporator 14, a temperature of the heat medium is lowered due to heat release to the refrigerant, and when the heat medium flows into the condenser 12, the temperature of the heat medium is increased due to heat absorption from the refrigerant.

[0063] In a case where the series connection CC is set, the heat medium is circulated between the condenser 12 and the evaporator 14 while repeating the temperature increase by the condenser 12 and the temperature decrease by the evaporator 14. In this case, since a continuous circuit is formed in the heat medium circuit 20, the heat medium can be pumped by at least one of the first pump 21 and the second pump 22. That is, in a case where the temperature control system 1 includes only the operation mode using the series connection CC, it is sufficient to include only one of the first pump 21 and the second pump 22.

[0064] A speed of the pumps 21 and 22 described below may be set so that at least one of the pumps 21 and 22 is operated.

[0065] From the viewpoint of obtaining the maximum amount of heat dissipation from the pumps 21 and 22, it is preferable that, even in the operation mode using the series connection CC, the two pumps 21 and 22 are operated and the rotational speed N of the pump 21 or the pump 22 is set to the maximum.

[0066] Each of the first to third switching valves 31 to 33 is an electric valve capable of performing opening and closing control based on a command from the control device 5, and is configured to switch a flow channel of the heat medium in accordance with each operation mode.

[0067] As the first to third switching valves 31 to 33, the appropriate number of electric valves having an appropriate structure can be interchangeably used to set a channel required to realize a required operation mode to the heat medium circuit 20. [Control device configuration]

[0068] As in Fig. As shown in Figure 3, the control device 5 corresponds to a computer that includes a memory 501, a computing unit 502, a storage unit 503, and an input and output unit 504. The "computer" also includes a programmable logic controller (PLC). The control device 5 operates in accordance with a computer program read from and executed by the storage unit 503.

[0069] In each operation mode, the control device 5 can increase or decrease a cooling capacity and a heating capacity, respectively, by performing drive control of the compressor 11 and increasing or decreasing a circulation flow rate of a refrigerant based on the computer program read and executed by the storage unit 503.

[0070] For example, the control device 5 can control an indoor temperature to a target temperature such as an outside air temperature, a blowing temperature of conditioned air, a temperature of a heat medium, or a temperature of a refrigerant by detecting a physical quantity correlated with the indoor temperature via the sensors 61 and 62 and performing feedback control of controlling, for example, a rotation speed of the compressor 11 such that a deviation between the detected value and the target value is resolved.

[0071] Furthermore, the control device 5 is configured to adjust the rotational speed N of a pumping mechanism of the pumps 21 and 22.

[0072] In the present embodiment, the same rotation speed N is set for the pumps 21 and 22, but the present disclosure is not limited thereto. Different rotation speeds N may be set for the pumps 21 and 22.

[0073] The control device 5 generates, for example, a control command indicating a reference speed of each of the pumps 21 and 22 determined for each operating mode.

[0074] The reference speed is determined, for example, as follows and is stored in the storage unit 503. Cooling mode: first speed N1 Heat pump mode: first speed N1 Heating mode: second speed N2

[0075] The second speed N2 corresponds, for example, to 1.2 to 2 times the first speed N1.

[0076] The second speed N2 may be a maximum speed corresponding to a maximum axial power delivered by a motor to a pump mechanism of the pump.

[0077] Adjustment of the speed N of pumps 21 and 22 is carried out at least in the heating mode HT among several operating modes.

[0078] For example, in a case where the heat pump mode HP is set at startup of the temperature control system 1, or when the operation mode is switched from the heat pump mode HP to the heating mode HT, the control device 5 generates a control command S HT , which corresponds to the heating mode HT, for pumps 21 and 22.

[0079] Then, a drive circuit unit 21D provided at the first pump 21 drives the first pump 21 at the second speed N2 by applying a drive current corresponding to the control command S HT to a motor 21M. In the same way, a drive circuit unit 22D provided at the second pump 22 drives the second pump 22 at the second speed N2 by applying a drive current corresponding to the control command S HT corresponds to a 22M motor.

[0080] The rotational speed N of each of the pumps 21 and 22 can be controlled, for example, by increasing or decreasing a frequency or a duty cycle of the drive current applied to the motors 21M and 22M. [Description of operating mode]

[0081] First, the Fig. 1 briefly describes the heat pump mode HP. Heat pump mode HP (Fig. 1):

[0082] The heat pump mode HP corresponds to a mode of heating the cabin 8 and heats the cabin 8 by drawing heat from outside air as a heat source to a high-temperature heat medium having a temperature higher than outside air temperature and transporting the heat to the cabin 8.

[0083] The temperature control system 1 operates in the HP heat pump mode by using parallel circuits C1 and C2. A low-temperature heat medium flowing out of the evaporator 14 flows into the outdoor heat exchanger 23 via the second switching valve 32, as indicated by a solid line arrow. The heat medium that absorbs heat from the outside air flows back to the evaporator 14 via the first switching valve 31 and the evaporator flow control valve 14V.

[0084] A refrigerant is evaporated by absorbing heat from the heat medium flowing into the evaporator 14 and is sucked into the compressor 11. The refrigerant discharged from the compressor 11 is condensed by releasing heat to the heat medium in the condenser 12, and the heat medium is heated accordingly.

[0085] The high-temperature heat medium flowing out of the condenser 12 flows into the cabin heat exchanger 25 via the third switching valve 33, as indicated by a one-dotted line arrow. The heat medium that heats the cabin 8 flows back to the condenser 12 via the first switching valve 31 and the condenser flow control valve 12V.

[0086] In the heat pump mode HP, the outside air is used as a part of the heat source, and thus it is possible to ensure a heat capacity while suppressing an increase in power of the compressor 11, the pumps 21 and 22, and the like. Heating mode HT (Fig. 2):

[0087] Next, the heating mode HT, which is an operation mode using the series connection CC, will be described with reference to Fig. 2. In a case where an outside air temperature is significantly lower than 0 °C, for example, the outside air temperature is lowered to -20 °C or lower, the amount of heat that can be absorbed from a heat medium from outside air in the heat pump mode HP described above is reduced, a suction refrigerant density of the compressor 11 is reduced, and capacity of the compressor 11 is reduced.

[0088] Even in such a case, the heating mode HT for heating a temperature control target can be used as a heat source that gives heat to the heat medium passing through the pumps 21 and 22 set to have the higher rotation speed N than in other operation modes, while being a heat source that gives heat to a refrigerant passing through the compressor 11.

[0089] For example, in the HT heating mode, the amount of heat corresponding to the supplied power is supplied to a temperature control target in the same way as a resistance heating type electric heater. Therefore, the name of the HT heating mode is referred to as a "heating mode," but is not necessarily limited to this.

[0090] Since a heating mode HT0 at startup described below is a mode that accepts switching to the heating mode HT, the same name as the heating mode HT is used, but the name of the heating mode HT0 at startup is not necessarily limited to this.

[0091] A flow of the heat medium in the heating mode HT is determined with reference to Fig. 2. To prevent heat release from the heat medium to the outside air, the heat medium is guided to bypass the outdoor heat exchanger 23 through the outdoor heat exchanger bypass channel 24. In this case, the operation of the outdoor fan 23A can be stopped. The speeds N of the pumps 21 and 22 are set, for example, to the second speed N2.

[0092] The heat medium absorbing heat from the refrigerant via the condenser 12 flows into the cabin heat exchanger 25 via the third switching valve 33 and is supplied to heat an interior of the cabin 8. The heat medium flowing out of the cabin heat exchanger 25 flows into at least the evaporator 14 via the first switching valve 31 and the evaporator flow control valve 14V, among the evaporator 14 and the evaporator bypass passage 14A, and then releases heat to the refrigerant.

[0093] The heat medium flowing out of the evaporator 14 flows from the second switching valve 32 into the outdoor heat exchanger bypass passage 24, converges between the first switching valve 31 and the condenser flow control valve 12V, and then flows into at least the condenser 12 under the condenser 12 and the condenser bypass passage 12A and absorbs heat from the refrigerant.

[0094] Here, the pumps 21 and 22 are operated at a predetermined efficiency η, and simply, most of a loss, which is a product of axial power P output from the motors 21M and 22M to the pumps 21 and 22 and (1 - the efficiency η), is transferred to the heat medium as thermal energy. In the heating mode HT, since the rotational speed N of the pumps 21 and 22 is increased from the first rotational speed N1 in the heat pump mode HP and the like to the second rotational speed N2, a discharge flow rate of the heat medium by the pumps 21 and 22 is increased compared to a discharge flow rate in the other operation modes, and the amount of heat transferred from the pumps 21 and 22 to the heat medium is increased. In this way, the amount of heat released from the heat medium to the refrigerant in the evaporator 14 is increased, and the low pressure pL of the refrigerant circuit 10 is increased.

[0095] Fig. 4 shows a pH line diagram of a refrigerant, a refrigeration cycle Y1 (dashed line) in the heat pump mode HP and a refrigeration cycle Y2 (solid line) in the heating mode HT. The two refrigeration cycles Y1 and Y2 are under a condition where an outside air temperature is -20 °C.

[0096] In the heat pump mode HP, since the refrigerant needs to absorb heat from a heat medium flowing into the evaporator 14 after exchanging heat with the outside air at -20 °C, the low pressure pL is reduced.

[0097] On the other hand, in the heating mode HT, the heat medium flowing through the condenser 12 and the cabin heat exchanger 25 releases heat to the refrigerant via the evaporator 14, and the amount of heat introduced from the heat medium into the refrigerant is increased by increasing the rotational speeds N of the pumps 21 and 22, and thus, as shown in Fig. 4, the low pressure pL is increased compared to the heat pump mode HP. As a result, a density of the refrigerant sucked into the compressor 11 (hereinafter referred to as a compressor suction density ρ) is increased, the power of the compressor 11 is increased, and a circulation flow rate of the refrigerant is increased. Therefore, a heat capacity is improved.

[0098] In addition, the heat capacity is also improved by increasing the amount of heat to be absorbed from the refrigerant into the heat medium in the condenser 12 due to an increase in discharge flow rate of the heat medium by increasing the rotational speed N of the pumps 21 and 22.

[0099] In the HT heating mode, the heat medium flows through the outdoor heat exchanger bypass passage 24 while avoiding heat release to the outside air, receives heat generated by the power of the pumps 21 and 22, and further receives heat generated by the power of the compressor 11 from the refrigerant, and transports the heat to a temperature control target. With the HT heating mode, regardless of the outside air temperature, heating of the interior of the cabin 8 can be continued by operating through a system in which heat is not exchanged with the outside air, while increasing the amount of heat introduced into the refrigerant by increasing the rotational speeds N of the pumps 21 and 22. [Main effects and effects of this embodiment]

[0100] With the temperature control system 1 for a vehicle where a heat source is likely to be insufficient, even under a condition where heat absorption from outside air is insufficient due to an outside air temperature being significantly lower than 0°C, the insufficient heat source can be compensated for by increasing the power of the pumps 21 and 22 in the heating mode HT, and a heat capacity can be ensured. Therefore, a temperature in the cabin 8 can reach a target temperature in a short time compared to the heat pump mode HP.

[0101] Furthermore, in the heating mode HT using the series connection CC, since the condenser 12 and the evaporator 14 are connected in series, a temperature of a heat medium flowing out of the condenser 12 can be increased faster than in a case where the heat medium flows in parallel with the condenser 12 and the evaporator 14. Moreover, since the amount of heat medium circulating in the cabin heat exchanger 25 is large, the amount of heat exchanged between the heat medium and the air is large. [First modification example]

[0102] In the heat pump mode HP ( Fig. 1) The rotational speed N of the second pump 22 corresponding to the high-pressure side circuit C2 may be set to a speed higher than the rotational speed N of the first pump 21, for example, to the second rotational speed N2 in the heating mode HT. In this case, the amount of heat absorbed by the condenser 12 from a refrigerant into a heat medium can be increased compared to a case where the rotational speed N of the second pump 22 is identical to the rotational speed N of the first pump 21 and the amount of heat discharged from the second pump 22 is small, to improve a heat capacity.

[0103] For the first pump 21 corresponding to the low-pressure side circuit C1, it is not necessary to increase the rotational speed N in order to ensure a temperature difference between an outside air required for heat absorption from the outside air and the heat medium of the low-pressure side circuit C1. [Second modification example]

[0104] The rotational speed N of the pumps 21 and 22 in the heating mode HT can be adjusted only in a case where a temperature of a heat medium is lower than a predetermined temperature. For example, in a case where the temperature of the heat medium flowing out of the evaporator 14 is lower than a threshold value T1, a heat capacity is not necessarily sufficient.

[0105] Therefore, the control device 5 determines, for example, whether a temperature detected by the temperature medium temperature sensor 65 ( Fig. 2) that detects the temperature of the temperature medium between an outlet of the condenser 12 and an inlet of the cabin heat exchanger 25 is lower than the threshold T1 or not. In a case where the detection temperature is lower than the threshold T1 as a result of the determination, the control device 5 sets the rotational speeds N of the pumps 21 and 22, for example, to the rotational speed N that is higher than a rotational speed in the other operation mode, for example, the second rotational speed N2. [Third modification example]

[0106] Furthermore, in the heating mode HT, the speed N of the pumps 21 and 22 can be set to a speed in accordance with a heat load.

[0107] Here, the "air conditioning load," which is either a cooling load or a heating load, is defined by formula (1). The air temperature in the formula is strictly air enthalpy. The air volume in the formula is strictly a mass flow rate. Air conditioning load L=air volume Q×(target outlet temperature TT−intake air temperature TI)

[0108] The heating load is increased when an outside air temperature is reduced.

[0109] The air volume Q refers to a mass flow rate of air delivered to the cabin heat exchanger 25 by the cabin blower 25A while the vehicle is traveling. The air volume Q can be determined, for example, from the number of settings by an occupant or from the number of settings by the temperature control system 1 and a blowing mode (face / foot / defogger or the like).

[0110] The target outlet temperature T Tis a target temperature of air blown from the HVAC unit U into the cabin 8 and is set from a target temperature of air in the cabin 8. The target blow-out temperature T T is detected by the temperature sensor 62.

[0111] The intake air temperature T I refers to a temperature of air introduced into the cabin heat exchanger 25 by the cabin blower 25A and the vehicle running. The intake air temperature T I corresponds to an indoor temperature in the cabin 8 detected by an indoor temperature sensor (not shown) in a case where indoor air circulation is set, and corresponds to the outside air temperature detected by the outside air temperature sensor 61 in a case where the introduction of the outside air is set.

[0112] In a case where the outside air temperature is significantly lower than 0 °C, a difference ΔT between T T and T I large, so the heating load is high.

[0113] In the heating mode HT, the control device 5 can give the high speed N corresponding to the air conditioning load L to the pumps 21 and 22 when the air conditioning load L calculated by formula (1) is relatively high, and can give the low speed N corresponding to the air conditioning load L to the pumps 21 and 22 when the air conditioning load L is relatively low. The speed N is increased or decreased in accordance with the air conditioning load L, so that a heat capacity can be variably controlled.

[0114] With the third modification example, it is possible to operate the air conditioner with low power consumption by suppressing current while ensuring sufficient heat capacity for the air conditioning load L. [Fourth modification example]

[0115] In the heating mode HT, at least the low pressure pL among the low pressure pL and the high pressure pH of the refrigerant circuit 10 can be controlled by controlling the speeds N of the pumps 21 and 22.

[0116] In the heating mode HT, the control device 5 controls the low pressure pL to be equal to or higher than 0.2 MPa and equal to or lower than 1.2 MPa.

[0117] Further, in the heating mode HT, it is preferable that the control device 5 controls the high pressure pH to be equal to or less than 2.8 MPa. [Characteristic of low-pressure compressor power in heating mode]

[0118] Fig. Figure 5 shows a relationship between the low-pressure pL (horizontal axis) and capacity (vertical axis) of the compressor 11 in the heating mode HT. This is based on a result calculated under a condition where the high-pressure pH is constant and a rotational speed of the compressor 11 is also constant. A solid line indicates a case of R1234yf, and a one-dot-dash line indicates a case of propane (R290). For all refrigerants, characteristics LPP of low-pressure compressor capacity have a curve in a shape of a mountain, and a peak is approximately 1 MPa. Hereinafter, unless otherwise specified, the same applies to the two refrigerants in common.

[0119] A range of a value of the Fig. The low pressure pL shown in Figure 5 is 0.1 MPa or more and 2.1 MPa or less. The low pressure pL increases from 0.1 MPa to the peak while gradually decreasing, and decreases while gradually increasing the decreasing rate beyond the peak.

[0120] When the low pressure pL is increased from 0.1 MPa to 1 MPa, the capacity of the compressor 11 is increased. Therefore, a heat capacity based on the amount of heat corresponding to the capacity of the compressor 11 is also increased. However, in a case where the low pressure pL is excessively high beyond the peak, the heat capacity sufficient for a low outside air temperature cannot be obtained due to the capacity decrease. Since the low pressure pL is gradually reduced from the peak, the heat capacity of up to 1.2 MPa can be acceptable even after exceeding the peak.

[0121] Such a property LPP of low pressure compressor power corresponds to the cooling circuit Y2 ( Fig. 4) in the heating mode HT. In a case where the low pressure pL is increased, the power of the compressor 11 is increased in accordance with an increase in compressor suction density ρ, but a pressure difference Δp between the high pressure pH and the low pressure pL is decreased. Therefore, the power of the compressor 11 is decreased in accordance with a decrease in enthalpy difference Δh ( Fig. 4). That is, while the low pressure pL is increased to 1 MPa, the power increase due to the increase in the compressor suction density ρ is greater than the power decrease due to the decrease in enthalpy difference Δh.

[0122] Based on the low-pressure compressor performance characteristic LPP, even if the low pressure pL is increased in the HT heating mode, the effect of increasing the heat capacity cannot be obtained because the heat capacity is not increased in a case where the low pressure pL is too low or too high. Therefore, in order to ensure sufficient heat capacity at a low outside air temperature, the control device 5 maintains the low pressure pL at 0.2 MPa or more and 1.2 MPa or less in the HT heating mode.

[0123] In contrast to the heat pump mode HP, in the heating mode HT the control of the low pressure pL in this way is based on the fact that heat is not absorbed from outside air into a heat medium, and thus the low pressure pL can be freely increased to a pressure equal to or higher than a pressure corresponding to a saturated vapor pressure. [Characteristic of high-pressure compressor power in heating mode]

[0124] A relationship between the high-pressure pH and compressor capacity in the heating mode HT is not shown. Since the compressor capacity is gradually increased as the high-pressure pH is increased, the higher the high-pressure pH, the higher the heat capacity. From the viewpoint of sufficiently ensuring the heat capacity by increasing the pressure difference Δp, it is preferable to set the high-pressure pH to be as high as possible within a range in which a pressure tolerance of a device such as a casing of the compressor 11 is ensured. Therefore, the control device 5 preferably limits the high-pressure pH to, for example, 2 times or more of the low-pressure pL and 2.8 MPa or less in at least the heating mode HT. [Control of refrigerant pressure in heating mode]

[0125] The rotational speeds N of the pumps 21 and 22 can be increased or decreased in the heating mode HT to control the low pressure pL to the above value. In a case where the rotational speed N of the pumps 21 and 22 is changed, a flow rate at which a heat medium is circulated through a passage including the evaporator 14 of the heat medium circuit 20 is changed, and the amount of heat transferred from the pumps 21 and 22 to the heat medium is changed. Accordingly, the amount of heat released from the heat medium to a refrigerant in the evaporator 14 is changed, and thus the low pressure pL is changed.

[0126] The control device 5 can perform feedback control of giving the rotational speed N (control command) as the operation amount to the pumps 21 and 22 while detecting the low pressure pL detected by the low-pressure pressure sensor 63, so that a deviation between the detected value and a target pressure is resolved.

[0127] Furthermore, in the heating mode HT, the rotational speeds N of the pumps 21 and 22 can be increased or decreased to control the high-pressure pH to the value described above. In a case where the rotational speed N of the pumps 21 and 22 is changed, a flow rate at which the heat medium is circulated through a passage including the condenser 12 of the heat medium circuit 20 is changed. Accordingly, the amount of heat absorbed from the refrigerant to the heat medium in the condenser 12 is changed, and thus the high-pressure pH is changed.

[0128] The control device 5 may perform feedback control of giving the rotational speed N (control command) as the operation amount to the pumps 21 and 22 while detecting the high pressure pH detected by the high pressure sensor 64, so that a deviation between the detected value and the target pressure is resolved.

[0129] With the fourth modification example, the heat capacity can be reliably ensured by controlling the low pressure pL based on the low pressure power characteristic LPP in the heating mode HT to be 0.2 MPa or more and 1.2 MPa or less, and by increasing the rotational speeds of the pumps 21 and 22 in the heating mode HT in a range of 0.2 MPa or more and 1.2 MPa or less compared to the rotational speeds in the other operation modes. [Fifth modification example]

[0130] The temperature control system 1 according to the embodiment described above can Fig. 6 shown heating mode HT0 when starting up.

[0131] In the heating mode HT0 at startup, a heat medium flows into the outdoor heat exchanger 23, causing the heat medium to absorb heat from outside air via the outdoor heat exchanger 23. Furthermore, in order to prioritize heating of a refrigerant over heating an interior of the cabin 8, the heat medium is bypassed to the condenser bypass passage 12A without flowing into the condenser 12, thus preventing heat release of the refrigerant to the heat medium. Then, the heat medium flowing out of the cabin heat exchanger 25 releases heat from the refrigerant in the evaporator 14. It is preferable to stop the operation of the cabin blower 25A to suppress heat exchange between the air and the heat medium in the cabin heat exchanger 25.

[0132] For example, the rotational speed N of each of the first and second pumps 21 and 22 may be increased to the maximum rotational speed to increase the amount of heat introduced into the refrigerant in the heating mode HT0 at startup. In this way, in addition to the amount of heat applied to the refrigerant from the outside air via the heat medium, the amount of heat corresponding to the output of the first and second pumps 21 and 22 can be applied from the heat medium to the refrigerant, and the release of heat from the heat medium to the refrigerant is promoted by increasing a circulation flow rate of the heat medium. Therefore, switching to a steady operation of the refrigerant cycle 10 is promoted.Therefore, it is possible to heat the interior of the cabin 8 early by reducing a required time from a start-up of the temperature control system 1 to switching to the heating mode HT via the heating mode HT0 at start-up.

[0133] From an outlet of the outdoor heat exchanger 23 to an inlet of the evaporator 14 via the condenser bypass passage 12A and the cabin heat exchanger 25, heat exchange between the heat medium and the refrigerant and heat exchange between the heat medium and the air are suppressed. The heat medium absorbs heat from the outside air and transports the heat to the evaporator 14, through which the refrigerant flows, passing through the condenser bypass passage 12A and the cabin heat exchanger 25.

[0134] While the vehicle is stopped in a state where the outside air temperature is extremely low and below freezing, a temperature of each of the heat medium and the refrigerant is lowered to the same level as the outside air temperature. Therefore, in a case where startup of the temperature control system 1 is started and the compressor 11 is started immediately after a refrigeration cycle is started, the low pressure pL of the refrigerant circuit 10 is lowered by cooling the heat medium with the refrigerant, and an evaporation temperature of the refrigerant is lower than the outside air temperature. Meanwhile, with the heating mode HT0 at startup, the heat absorbed from the outside air by the heat medium and the heat discharged from the pumps 21 and 22 are continuously transferred to the refrigerant, so that the low pressure of the refrigerant circuit 10 is gradually increased and the evaporation temperature is also increased.Thereafter, the low pressure pL is increased to the predetermined value, and the refrigerant cycle 10 is operated in a steady-state mode, so that a temperature control target can be heated by the heat extracted from the power of the compressor 11 to the heat medium. Therefore, the operation mode can be switched to the heating mode HT.

[0135] Since heat absorption from the outside air is insufficient in a case where a temperature of the heat medium is higher than the outside air temperature, the control device 5 may cause the temperature control system 1 to switch to the HT heating mode in a case where the temperature of the heat medium approaches the outside air temperature. For example, the operation mode may be switched to the HT heating mode in a case where the temperature of the heat medium is higher than a threshold value T3, which is lower than the outside air temperature by a predetermined temperature difference α (for example, -20 °C).

[0136] In addition to the above, it is possible to select the configurations described in the above-described embodiment or to change the configurations to other configurations as needed.

[0137] In addition to the cabin heat exchanger 25 as the temperature control device, the temperature control system 1 may include another temperature control device, such as a battery device, or may replace the cabin heat exchanger 25 with the other temperature control device. In this case, the heat medium circuit 20 includes a channel for cooling or heating the other temperature control device with a heat medium. [Attachments]

[0138] From the above disclosure, the following configurations are understood. [1] A temperature control system (1) for a vehicle, comprising: a refrigerant circuit (10) configured to include a compressor (11), a high-pressure side heat exchanger (12), a pressure reducing unit (13), and a low-pressure side heat exchanger (14), and circulates a refrigerant in accordance with a refrigeration cycle; and a heat medium circuit (20) configured to circulate a heat medium that exchanges heat with the refrigerant, wherein the heat medium circuit (20) contains: the high-pressure side heat exchanger (12), which carries out heat exchange between the refrigerant and the heat medium, the low-pressure side heat exchanger (14), which carries out heat exchange between the refrigerant and the heat medium, a pump (21, 22) configured to pump the heat medium, an outdoor heat exchanger (23) which carries out heat exchange between outside air and the heat medium, a temperature control device (25) corresponding to a temperature control target heated or cooled by the heat medium or used to heat or cool the temperature control target, and an external bypass channel (24) which guides the heat medium so that it bypasses the external heat exchanger (23),

[0139] In the temperature control system (1), as an operation mode, a power heat source mode (HT) is provided, which is a mode in which the heat medium flowing out of the high-pressure side heat exchanger (12) flows into the low-pressure side heat exchanger (14) via the temperature control device (25) and further flows into the high-pressure side heat exchanger (12) via the outdoor heat exchanger bypass channel (24), and power of the compressor (11) and power of the pump (21, 22) are used as a heat source. the temperature control system (1) further comprises: a control device (5) configured to variably adjust a rotational speed (N) of the pump (21, 22), and the control device (5) is configured to change the rotational speed (N) of the pump (21, 22) into at least a first rotational speed (N1) set for the pump (21, 22) in another operating mode (HP) and a second rotational speed (N2) higher than the first rotational speed (N1), and to set the second rotational speed (N2) for the pump (21, 22) in the power heat source mode (HT).

[0140] [2] The temperature control system (1) according to [1], wherein the heat medium circuit (20) includes a first pump (21) and a second pump (22) as the pump (21, 22), and in the temperature control system (1), as the further operating mode (HP), a heat pump mode in which a low-pressure side circuit (C1), in which the heat medium is circulated by the first pump (21) via the low-pressure side heat exchanger (14) and the outdoor heat exchanger (23), and a high-pressure side circuit (C2), in which the heat medium is circulated by the second pump (22) via the high-pressure side heat exchanger (12) and the temperature control device (25), are formed, is provided.

[0141] [3] The temperature control system for vehicle according to [2], wherein the control device (5) is configured to set the rotational speed (N) higher than the first rotational speed (N1) set for the first pump (21) for the second pump (22) in the heat pump mode (HP).

[0142] [4] Temperature control system for vehicle according to one of [1] to [3], wherein the control device (5) is configured to set the second rotational speed (N2) for the pump (21, 22) when a temperature of the heat medium is lower than a predetermined temperature in the power heat source mode (HT).

[0143] [5] Temperature control system for vehicle according to one of [1] to [4], wherein the control device (5) is configured to adjust the rotational speed (N) in accordance with a heat load for the pump (21, 22) in the power heat source mode (HT).

[0144] [6] Temperature control system for vehicle according to one of [1] to [5], wherein the control device (5) is configured to control at least one low pressure (pL) among the low pressure (pL) and a high pressure (pH) of the refrigerant circuit (10) by controlling the rotational speed (N) based on a control command for the pump (21, 22) in the power heat source mode (HT).

[0145] [7] Temperature control method for vehicle using a temperature control system (1), wherein the temperature control system (1) includes: a refrigerant circuit (10) configured to include a compressor (11), a high-pressure side heat exchanger (12), a pressure reducing unit (13), and a low-pressure side heat exchanger (14), and circulates a refrigerant in accordance with a refrigeration cycle, and a heat medium circuit (20) configured to circulate a heat medium that exchanges heat with the refrigerant, and the heat medium circuit (20) contains: the high-pressure side heat exchanger (12), which carries out heat exchange between the refrigerant and the heat medium, the low-pressure side heat exchanger (14), which carries out heat exchange between the refrigerant and the heat medium, a pump (21, 22) configured to pump the heat medium, an outdoor heat exchanger (23) which carries out heat exchange between outside air and the heat medium, a temperature control device (25) corresponding to a temperature control target heated or cooled by the heat medium or used to heat or cool the temperature control target, and an outdoor heat exchanger bypass channel (24) that guides the heat medium to bypass the outdoor heat exchanger (23), the temperature control method comprising: Setting, in a power heat source mode (HT), which is a mode in which the heat medium flowing out of the high-pressure side heat exchanger (12) flows into the low-pressure side heat exchanger (14) via the temperature control device (25) and further flows into the high-pressure side heat exchanger (12) via the outdoor heat exchanger bypass channel (24), and power of the compressor (11) and power of the pump (21, 22) are used as a heat source, a second rotation speed (N2) higher than a first rotation speed (N1) set for the pump (21, 22) in another operation mode (HP), for the pump (21, 22). List of reference symbols 1 temperature control system 5 Control device 8 cabins 10 Refrigerant circuit 11 Compressor 12 Condenser (high-pressure side heat exchanger) 12A Condenser bypass channel (high-pressure side bypass channel) 12V capacitor flow control valve (high-pressure side flow control valve) 13 Expansion valve (pressure reducing unit) 14 Evaporator (low-pressure side heat exchanger) 14A Evaporator bypass channel (low pressure side bypass channel) 14V evaporator flow control valve (low pressure side flow control valve) 15 reserve tank 16 communication channels 17 On / off valve 20 Heat medium circuit 21 first pump (pump) 21D drive circuit unit 21M engine 22 second pump (pump) 22D drive circuit unit 22M engine 23 outdoor heat exchangers 23A outdoor fan 24 Outdoor heat exchanger bypass channel 25 cabin heat exchangers (temperature control device) 25A cabin fan 31 first changeover valve 32 second switching valve 33 third changeover valve 61 Outside air temperature sensor 62 Temperature sensor 63 Low pressure pressure sensor 64 High pressure pressure sensor 65 Heat medium temperature sensor 401, 402 pipe 501 memory 502 Calculation unit 503 storage unit 504 Input and output unit C1 low-pressure side circuit C2 high-pressure side circuit CC series connection HP heat pump mode HT heating mode (power heat source mode) HT0 heating mode when starting LPP compressor performance characteristic U HVAC unit Y1, Y2 cooling circuit pH high pressure pL low pressure Δh enthalpy difference Δp pressure difference QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 6083304

[0006]

Claims

[1] Temperature control system for vehicle, comprising: a refrigerant circuit configured to include a compressor, a high-pressure side heat exchanger, a pressure reducing unit, and a low-pressure side heat exchanger, and circulates a refrigerant in accordance with a refrigeration cycle; and a heat medium circuit configured to circulate a heat medium that exchanges heat with the refrigerant, where the heat medium circuit contains: the high-pressure side heat exchanger, which carries out heat exchange between the refrigerant and the heat medium, the low-pressure side heat exchanger, which carries out heat exchange between the refrigerant and the heat medium, a pump configured to pump the heat medium, an outdoor heat exchanger that performs heat exchange between outside air and the heat medium, a temperature control device corresponding to a temperature control target heated or cooled by the heat medium or used to heat or cool the temperature control target, and an outdoor heat exchanger bypass channel that guides the heat medium to bypass the outdoor heat exchanger, In the temperature control system, as an operation mode, a power heat source mode is provided, which is a mode in which the heat medium flowing out of the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device and further flows into the high-pressure side heat exchanger via the outdoor heat exchanger bypass channel, and power of the compressor and power of the pump are used as a heat source. the temperature control system further comprises: a control device configured to variably adjust a speed of the pump, and the control device is configured to change the speed of the pump to at least a first speed set for the pump in another operating mode and a second speed higher than the first speed, and to set the second speed for the pump in the power heat source mode. [2] Temperature control system for vehicle according to claim 1, wherein the heat medium circuit includes a first pump and a second pump as the pump, and in the temperature control system, as the further operation mode, a heat pump mode in which a low-pressure side circuit in which the heat medium is circulated by the first pump via the low-pressure side heat exchanger and the outdoor heat exchanger, and a high-pressure side circuit in which the heat medium is circulated by the second pump via the high-pressure side heat exchanger and the temperature control device are formed, is provided. [3] The temperature control system for vehicle according to claim 2, wherein the control device is configured to set the rotation speed higher than the first rotation speed set for the first pump for the second pump in the heat pump mode. [4] The temperature control system for vehicle according to any one of claims 1 to 3, wherein the control device is configured to set the second rotation speed for the pump when a temperature of the heat medium is lower than a predetermined temperature in the power heat source mode. [5] A temperature control system for a vehicle according to any one of claims 1 to 3, wherein the control device is configured to adjust the rotational speed in accordance with a heat load for the pump in the power heat source mode. [6] The temperature control system for vehicle according to any one of claims 1 to 3, wherein the control device is configured to control at least one of the low pressure and the high pressure of the refrigerant circuit by controlling the rotational speed based on a control command for the pump in the power heat source mode. [7] Temperature control method for vehicle using a temperature control system, wherein the temperature control system includes: a refrigerant circuit configured to include a compressor, a high-pressure side heat exchanger, a pressure reducing unit, and a low-pressure side heat exchanger, and circulates a refrigerant in accordance with a refrigeration cycle, and a heat medium circuit configured to circulate a heat medium that exchanges heat with the refrigerant, and the heat medium circuit contains: the high-pressure side heat exchanger, which carries out heat exchange between the refrigerant and the heat medium, the low-pressure side heat exchanger, which carries out heat exchange between the refrigerant and the heat medium, a pump configured to pump the heat medium, an outdoor heat exchanger that performs heat exchange between outside air and the heat medium, a temperature control device corresponding to a temperature control target heated or cooled by the heat medium or used to heat or cool the temperature control target, and an outdoor heat exchanger bypass channel that guides the heat medium to bypass the outdoor heat exchanger, the temperature control method comprising: Setting, in a power heat source mode, which is a mode in which the heat medium flowing out of the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device and further flows into the high-pressure side heat exchanger via the outdoor heat exchanger bypass channel, and power of the compressor and power of the pump are used as a heat source, a second speed higher than a first speed set for the pump in another operation mode, for the pump.

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