WO2024058123A1

WO2024058123A1 - Vehicle temperature control system and temperature control method

Info

Publication number: WO2024058123A1
Application number: PCT/JP2023/033043
Authority: WO
Inventors: 知康足立; 徹三鵜飼; 信也中川; 崇幸小林; 裕之山本; 英人野山; 克弘齊藤; 昌俊森下
Original assignee: 三菱重工サーマルシステムズ株式会社
Priority date: 2022-09-16
Filing date: 2023-09-11
Publication date: 2024-03-21
Also published as: JP7325593B1; JP2024043205A

Abstract

Provided are a vehicle temperature control system and method which are capable of ensuring heating capacity even when the outdoor temperature is low, and capable of heating a thermal load via more appropriate mode switching.　This vehicle temperature control system is equipped with: a coolant circuit; a heating medium circuit; a heat pump mode in which a low-pressure-side circuit through which a heating medium circulates and a high-pressure-side circuit through which a heating medium circulates are formed; a compressor heat source mode in which a heating medium discharged from a high-pressure-side heat exchanger flows into a low-pressure-side heat exchanger via a temperature control device, passes through an outdoor bypass path, and flows into the high-pressure-side heat exchanger; and a mode selection unit. The mode selection unit is configured so as to select the heat pump mode when the detected outdoor temperature is higher than a switching outdoor temperature pertaining to the outdoor temperature/heating capacity properties intersection for each of the heat pump mode and the compressor heat source mode, and to select the compressor heat source mode when the outdoor temperature is lower than said switching outdoor temperature.

Description

Vehicle temperature control system and temperature control method

The present disclosure relates to a temperature control system installed in a vehicle and a temperature control method using the same.

Vehicles such as electric vehicles and so-called hybrid vehicles that obtain driving power from engines and electric motors tend to lack heat sources, but in addition to air conditioning functions required for vehicles such as heating, cooling, dehumidification, and ventilation, Thermal management and waste heat utilization of in-vehicle equipment such as batteries is required. In order to meet these demands, in addition to heat pump systems, conventional systems include systems that include a chiller to cool the battery and a heater to warm the battery, or a system that uses a pump to transport water heated by the exhaust heat of a radiator to the temperature controlled target. A number of systems have been used, such as the

A vehicle heat management system that can integrate air conditioning and equipment heat management includes a primary loop in which refrigerant circulates according to the refrigeration cycle, and a heat medium (such as water) that transfers heat to and from the refrigerant in the primary loop, which is mounted on the vehicle using a pump. A system including a secondary loop for transporting to equipment has been proposed (for example, Patent Document 1).

The heat management system described in Patent Document 1 includes a first heat medium circuit in which an evaporator of a refrigerant circuit and a heat medium outside air heat exchanger are arranged, and a condenser of the refrigerant circuit and a heater core of a cabin air conditioning unit are arranged. and a second heat medium circuit. The first heat medium circuit and the second heat medium circuit are in an unconnected state (unconnected mode) and a connected state assuming low outside temperature by switching the flow paths by the first switching means and the second switching means. (concatenated mode).

In the uncoupled mode, a heat pump operation is performed in which heat from the outside air is pumped into the heat medium of the second heat medium circuit. In the coupled mode, the heat medium flowing out from the evaporator is not flowed into the heat medium outside air heat exchanger, but is combined with the heat medium flowing out from the condenser, and the heat medium is flowed into the evaporator and condenser in parallel. . At this time, the first heat medium circuit and the second heat medium circuit are connected via the evaporator and the condenser.

In the above-mentioned Patent Document 1, based on a physical quantity (ρ2) related to the heat medium temperature in the second heat medium circuit in the connected mode, when the following formula is satisfied, it is estimated that the amount of heat that can be input to the heat medium of the second heat medium circuit in the connected mode is greater than the amount of heat that can be input to the heat medium of the second heat medium circuit in the unconnected mode, and therefore the mode is switched from the unconnected mode to the connected mode.
ρ2>A1×ρ1
Here, ρ1 is the density of the refrigerant sucked into the compressor in the non-connected mode, ρ2 is the density of the refrigerant sucked into the compressor 11 in the non-connected mode, and A1 is the coefficient of performance (COP) of the refrigeration cycle in the non-connected mode.

Patent No. 6083304

In Patent Document 1, as a condition for switching from a non-coupled mode corresponding to heat pump operation to a coupled mode, an index based on the compressor suction density in the non-coupled mode and the coupled mode and COP according to the outside temperature is used. is used. These mode switching conditions are such that the amount of heat input to the heat medium in the uncoupled mode is compared with the amount of heat input to the heat medium in the coupled mode, and the one with the larger amount of heat input is selected. In other words, although Patent Document 1 aims to secure more sufficient heating capacity, there is a possibility that the power consumed for heating will increase.

Further, in the connection mode of Patent Document 1, the heat medium flowing out from the evaporator and the heat medium flowing out from the condenser are mixed, so that the temperature becomes intermediate between the temperatures of the respective heat mediums before mixing. Flows into the evaporator and condenser. Therefore, compared to the non-coupled mode, it takes time for the temperature of the heat medium flowing out from the condenser to rise. Furthermore, since the flow rate of the heat medium flowing into the indoor heat exchanger decreases, there is room for improvement in the heating capacity.

The present disclosure provides temperature control for vehicles that can ensure heating capacity even in situations where it is difficult to secure a heat source due to low outside temperatures, and that can heat the temperature-controlled target by switching modes more appropriately. The purpose is to provide a system and temperature control method.

The present disclosure relates to a temperature control system for a vehicle, which includes a refrigerant circuit that includes a compressor, a high-pressure side heat exchanger, a pressure reduction section, and a low-pressure side heat exchanger, and is configured to allow refrigerant to circulate according to a refrigeration cycle; and a heat medium circuit configured to allow circulation of a heat medium that transfers heat to and receives heat from the heat transfer medium.
The heat medium circuit includes a high-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium, and a low-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium, both of which are configured to be able to pump the heat medium. A pump and a second pump, an outdoor heat exchanger that exchanges heat between outside air and a heat medium, and a temperature control object that corresponds to a temperature control object that is heated or cooled by the heat medium or that is used for heating or cooling the temperature control object. and an outdoor bypass path that detours the heat medium from the outdoor heat exchanger.
The temperature control system has two operating modes: a low-pressure side circuit in which a heat medium circulates through a low-pressure side heat exchanger and an outdoor heat exchanger by a first pump, and a second circuit in which a heat medium circulates through a high-pressure side heat exchanger and temperature control equipment. In the heat pump mode, a circulating high pressure side circuit is formed, and the heat medium flowing out from the high pressure side heat exchanger flows into the low pressure side heat exchanger via the temperature control device, and further passes through the outdoor bypass route. A compressor heat source mode that flows into the high-pressure side heat exchanger, a mode selection section configured to be able to select a heat pump mode or a compressor heat source mode, and an outside temperature sensor that detects outside air temperature.
The mode selection section selects an outside air temperature that corresponds to the intersection of the outside air temperature and heating capacity characteristics of the heat pump mode and the compressor heat source mode, or a switching outside air temperature that is set to a temperature lower than the outside air temperature of the intersection. The heat pump mode is selected when the outside air temperature detected by the air temperature sensor is high, and the compressor heat source mode is selected when the outside air temperature is low.

Furthermore, the present disclosure can also be applied to a temperature control method for vehicles.

According to the present disclosure, the mode selection unit determines mode selection using a switching outside air temperature that is set based on correlation data of outside air temperature-heating capacity characteristics of each of the heat pump mode and the compressor heat source mode as a threshold. . Then, the heat pump mode or the compressor heat source mode can be appropriately selected based on the heating capacity that depends on the outside air temperature.
For example, even if compressor heat source mode is more suitable than heat pump mode in terms of the amount of heat input into the heat medium that is heat exchanged with the high-pressure heat exchanger, based on the characteristics of outside air temperature and heating capacity, , it is possible to select a heat pump mode that can be operated with less power by absorbing heat from the outside air. Then, if the heating capacity obtained by the heat pump mode is sufficient for the required heating capacity, the compressor heat source mode, which obtains the necessary amount of heat by supplying power to the compressor, will not be selected, making economical operation possible. It becomes possible.

When in the compressor heat source mode, the high-pressure side heat exchanger and the low-pressure side heat exchanger are connected in series, so the heat medium flows in parallel to the high-pressure side heat exchanger and the low-pressure side heat exchanger. The temperature of the heat medium flowing out from the high-pressure side heat exchanger can be raised more quickly than in the case where the heat exchanger flows out from the high-pressure side heat exchanger. Furthermore, since the amount of heat medium circulated through the temperature control device is large, the amount of heat exchanged between the heat medium and the object of temperature control becomes large.

Furthermore, in the compressor heat source mode, the heat medium that has passed through the high-pressure side heat exchanger and the indoor heat exchanger radiates heat to the refrigerant by the low-pressure side heat exchanger, so that the low pressure in the refrigerant circuit is lower than in the heat pump mode. As the density of the refrigerant sucked into the compressor increases accordingly, the circulating flow rate of the refrigerant increases. Since the heat exchange ability is improved by increasing the refrigerant circulation flow rate, and the heating ability can be improved, the temperature of the temperature-controlled object can quickly reach the target temperature.

According to the heat exchange system, by having at least a compressor heat source mode, even in situations where it is difficult to secure a heat source due to low outside temperatures, the heating capacity can be increased while supplying the compressor with the power necessary to secure the heat source. can be guaranteed.

FIG. 1 is a circuit diagram showing a vehicle temperature control system according to an embodiment of the present disclosure (heat pump mode). FIG. 2 is a diagram showing an operating state of the system shown in FIG. 1 in a heater mode. FIG. 2 is a block diagram showing the hardware configuration of a control device including a mode selection section. (a) and (b) are graphs showing the outside air temperature vs. heating capacity characteristics in the heat pump mode and the heater mode, respectively. FIG. 3 is a flow diagram showing an example of mode determination. It is a graph for explaining mode selection according to a first modification example of the present disclosure. FIG. 3 is a circuit diagram showing a vehicle temperature control system according to a second modified example of the present disclosure (heater mode at startup).

Hereinafter, one embodiment of the present disclosure will be described with reference to the accompanying drawings.
[Embodiment]
The temperature control system 1 for a vehicle shown in FIG. 1 is applicable, for example, to an electric vehicle that does not have an engine and obtains driving force for running the vehicle from an electric motor for running, or for an electric vehicle that does not have an engine and receives driving force for running the vehicle from an engine and an electric motor. It is equipped on a vehicle (not shown) such as a so-called hybrid vehicle. The temperature control system 1 includes air conditioning such as heating and cooling, dehumidification, ventilation, etc. for the passenger compartment 8 in which passengers board, as well as in-vehicle devices such as a battery device (power supply device), a driving motor, and electronic devices that generate heat. Responsible for heat management, waste heat recovery, etc. The general term ``thermal management'' refers to air conditioning to the appropriate temperature and humidity, and controlling in-vehicle equipment to an appropriate temperature.
Electrical equipment and electronic devices included in the temperature control system 1 and other in-vehicle devices are supplied with electric power stored in an in-vehicle battery device. An on-vehicle battery device is charged from an external power source when the vehicle is stopped.

〔overall structure〕
The temperature control system 1 includes a refrigerant circuit 10 configured to allow circulation of a refrigerant, a heat medium circuit 20 configured to allow circulation of a heat medium that transfers heat to and from the refrigerant, and a temperature control system 1 configured to operate the temperature control system 1 in a predetermined manner. mode, and a control device 5 that controls the operating state of the temperature control system 1 according to the operating mode.
The temperature control system 1 also includes sensors such as an outside temperature sensor 51 that detects the outside temperature, and a room temperature sensor 52 that detects the temperature (room temperature) inside the vehicle interior 8.

The temperature control system 1 includes a plurality of operation modes selected by a passenger or by the control device 5. Among the operation modes of the temperature control system 1 of this embodiment, the heat pump mode HP (FIG. 1) and the heater mode HT (FIG. 2) will be described later.
The temperature control system 1 includes a mode selection unit 50 configured to be able to select between a heat pump mode HP and a heater mode HT. The mode selection unit 50 may be included in the control device 5.

[Refrigerant circuit configuration]
The refrigerant circuit 10 includes a compressor 11, a condenser 12, an expansion valve 13, and an evaporator 14, as an example of the configuration is shown in FIG. Refrigerant circulates in the refrigerant circuit 10 according to a refrigeration cycle.
As the refrigerant sealed in the refrigerant circuit 10, any known appropriate single refrigerant or mixed refrigerant can be used. For example, as the refrigerant of this embodiment, HFC (Hydro Fluoro Carbon) refrigerants such as R410A and R32, HFO (Hydro Fluoro Olefin) refrigerants such as R1234ze and R1234yf, or hydrocarbon (HC) refrigerants such as propane and isobutane are used. It is possible to use In particular, it is preferable to use R1234yf as the refrigerant in this embodiment.

When using the fluorocarbon-based or hydrocarbon-based refrigerants listed above, a subcritical refrigeration cycle is constructed in which the refrigerant pressure on the high-pressure side does not exceed the critical pressure of the refrigerant.
When carbon dioxide (CO ₂ ) 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 that case, the refrigerant can radiate heat by the high-pressure side heat exchanger like the condenser 12 of this embodiment, and the refrigerant can absorb heat by the low-pressure side heat exchanger like the evaporator 14 of this embodiment. A refrigerant constituting a transcritical refrigeration cycle, such as carbon dioxide refrigerant, can also be employed in the refrigerant circuit 10.

The compressor 11 corresponds to an electric compressor equipped with a motor driven by electric power supplied from a battery device (not shown). The compressor 11 uses a compression mechanism to adiabatically compress refrigerant sucked into a housing (not shown) and then discharges the refrigerant.
The condenser 12 exchanges heat between the refrigerant gas discharged from the compressor 11 and a heat medium.
The expansion valve 13 (pressure reducing section) reduces the pressure of the refrigerant flowing out from the condenser 12 to adiabatically expand the refrigerant. As the expansion valve 13, it is preferable to employ an electronic expansion valve whose opening degree can be controlled based on a command from the control device 5. However, it is also permissible to employ a temperature-type expansion valve or to employ a capillary tube instead of the expansion valve 13.

The evaporator 14 causes the refrigerant flowing out from the expansion valve 13 to exchange heat with a heat medium. The refrigerant evaporated by the evaporator 14 is sucked into the compressor 11.
An accumulator (gas-liquid separator), not shown, can be provided between the evaporator 14 and the compressor 11.

A relatively high refrigerant pressure (high pressure) is applied to the condenser 12, and a relatively low refrigerant pressure (low pressure) is applied to the evaporator 14. The refrigerant circulates through the refrigerant circuit 10 based on the pressure difference between high pressure and low pressure.
In FIG. 1, the flow of refrigerant on the low pressure side is shown by a thick solid line, and the flow of refrigerant on the high pressure side is shown by a thick broken line. The same applies to FIG. 2 and subsequent figures.

[Configuration of heat medium circuit]
The heat medium circuit 20 is configured such that a heat medium capable of exchanging heat with a refrigerant can be circulated through the condenser 12 and the evaporator 14 . The heat medium is used for cooling or heating at least one temperature-controlled object. One of the objects of temperature control in this embodiment corresponds to the air inside the vehicle compartment 8.
The heat medium sealed in the heat medium circuit 20 is a liquid such as water or brine that circulates through the heat medium circuit 20 while maintaining a liquid phase state. Examples of the brine include a mixture of water and propylene glycol, or a mixture of water and ethylene glycol.

As an example of the configuration is shown in FIG. 1, the heat medium circuit 20 includes a condenser 12, an evaporator 14, a first pump 21 and a second pump 22, an outdoor heat exchanger 23, and an outdoor bypass path 24. , an indoor 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 path switching valves.

In this 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. In the heat pump mode HP shown in FIG. 1, both the heat medium flowing out from the condenser 12 and the heat medium flowing out from the evaporator 14 flow through the first switching valve 31.

Preferably, the heat medium circuit 20 includes a condenser bypass path 12A that detours the heat medium from the condenser 12, and an evaporator bypass path 14A that detours the heat medium from the evaporator 14. In that case, the heat medium circuit 20 includes a condenser flow rate adjustment valve 12V configured to be able to adjust the flow rate ratio of the heat medium between the condenser 12 and the condenser bypass path 12A, and a condenser flow rate adjustment valve 12V that is configured to adjust the flow rate ratio of the heat medium between the condenser 12 and the condenser bypass path 12A, and the evaporator 14 and the evaporator bypass path 14A. It is preferable to include an evaporator flow rate adjustment valve 14V configured to be able to adjust the flow rate ratio of the heat medium.

The first pump 21 pumps the heat medium by sucking in the heat medium flowing out from the evaporator 14 and discharging it. The second pump 22 pumps the heat medium by sucking in the heat medium flowing out from the condenser 12 and discharging it.

The outdoor heat exchanger 23 exchanges heat between the outside air outside the vehicle compartment 8 and the heat medium. The outdoor heat exchanger 23 corresponds to, for example, a radiator placed near an air inlet of a vehicle. The outside air supplied to the outdoor heat exchanger 23 due to the running of the vehicle and the operation of the outdoor blower 23A radiates or absorbs heat based on the temperature difference between the outside air and the heat medium.

The outdoor bypass path 24 detours the heat medium from the outdoor heat exchanger 23.

The indoor heat exchanger 25 provides conditioned air into the vehicle interior 8 by exchanging heat between the air sent by the indoor blower 25A and a heat medium. The indoor blower 25A blows air (inside air) inside the vehicle interior 8 or outside air toward the indoor heat exchanger 25.
The HVAC (Heating, Ventilation, and Air Conditioning) unit U includes an indoor heat exchanger 25, an indoor blower 25A, and a duct (not shown) through which air sent by the indoor blower 25A flows.

By switching the flow of the heat medium by at least one of the first to

third switching valves

31, 32, and 33, the heat medium circuit 20 is configured such that the low pressure side circuit C1 and the high pressure side circuit C2 can be set in parallel. (FIG. 1), and is configured such that a series circuit CC can be set (FIG. 2).

A high-pressure side circuit C2 for the heat medium that flows out of the condenser 12 and returns to the condenser 12, and a low-pressure side circuit C1 that flows out of the evaporator 14 and returns to the evaporator 14 are separated from each other. Below, the low voltage side circuit C1 and the high voltage side circuit C2 may be referred to as parallel circuits C1 and C2.
The heat medium of the high pressure side circuit C2 including the condenser 12 and the heat medium of the low pressure side circuit C1 including the evaporator 14 are not mixed with each other.

In FIG. 1 showing 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 shown by a solid line, and the flow of a relatively high temperature heat medium (low temperature heat medium) circulating in the high pressure side circuit C2 is shown as a solid line. The flow of the heat medium (high-temperature heat medium) is shown by a dashed line. At this time, only the low temperature medium flows from position A to position B on the heat medium circuit 20, and only the high temperature medium flows from position C to position D. Paths in which neither the low-temperature heat medium nor the high-temperature heat medium is pumped are indicated by broken lines.

On the other hand, the series circuit CC corresponds to one continuous circuit including the evaporator 14 and the condenser 12 arranged in series. When the series circuit CC is set, for example, as shown in FIG. 2, the heat medium flowing out of the condenser 12 flows into the evaporator 14 and then into the condenser 12.
Also in FIG. 2 showing the series circuit CC, the flow of a relatively low-temperature heat medium is shown by a solid line, and the flow of a relatively high-temperature heat medium is shown by a dashed-dotted line. Referring to FIG. 2, unlike the case where parallel circuits C1 and C2 are set, the flow of the heat medium from the evaporator 14 to the condenser 12 is shown by a solid line, and the heat medium flows from the condenser 12 to the condenser 12. However, the flow of the heat medium until it flows into the evaporator 14 is shown by a dashed-dotted line. This means that when the heat medium flows into the evaporator 14, the temperature of the heat medium decreases due to heat radiation to the refrigerant, and when the heat medium flows into the condenser 12, the temperature of the heat medium rises due to heat absorption from the refrigerant. represents something to do.

When the series circuit CC is set, the heat medium circulates between the condenser 12 and the evaporator 14 while repeating a temperature increase by the condenser 12 and a temperature decrease by the evaporator 14. At this time, since one continuous circuit is formed in the heat medium circuit 20, the heat medium can be pumped only by at least one of the first pump 21 and the second pump 22.
However, even in the operation mode using the series circuit CC, a sufficient circulating flow rate of the heat medium in the heat medium circuit 20 can be obtained by operating the two

pumps

21 and 22.

All of the first to third switching valves 31 to 33 are electrically operated valves that can be controlled to open and close based on commands from the control device 5, and are configured to be able to switch the heat medium flow path.
The first to third switching valves 31 to 33 can be replaced with an appropriate number of electrically operated valves having an appropriate structure in order to set a path in the heat medium circuit 20 that is necessary to realize the required operation mode.

[Configuration of control device]
The control device 5 corresponds to a computer including a memory 501, a calculation section 502, a storage section 503, and an input/output section 504, as shown in FIG. "Computer" also includes programmable logic controllers (PLCs).

The control device 5 controls the rotation speed of the compressor 11 according to the heat load, and increases/decreases the circulating flow rate of the refrigerant, thereby increasing/decreasing the cooling capacity and the heating capacity, respectively.
Further, the control device 5 detects physical quantities correlated with the room temperature, such as room temperature, outside air temperature, heat medium temperature, refrigerant temperature or pressure, using a sensor, and eliminates the deviation between the detected value and the target value. The room temperature can be adjusted to the target temperature by feedback controlling the rotation speed of the compressor 11 and the like.

A computer program configured to be able to execute the mode selection unit 50 is stored in the storage unit 503.

By executing a computer program, the mode selection unit 50 selects heat pump mode HP and heater Select one of the modes HT.
The mode selection unit 50 may be included in a computer separate from the control device 5.

[Explanation of heat pump mode]
Next, with reference to FIG. 1, the operation of the temperature control system 1 in the heat pump mode HP will be described.
The heat pump mode HP corresponds to a mode that heats the inside of the vehicle interior 8, and heat is pumped up from the outside air as a heat source to a high-temperature heat medium whose temperature is higher than the outside air temperature, and transported to the vehicle interior 8. Heat the inside.
A circuit corresponding to the heat pump mode HP is set in the heat medium circuit 20 based on control commands for the first to third switching valves 31 to 33, the condenser flow rate adjustment valve 12V, and the evaporator flow rate adjustment valve 14V. .

In the heat pump mode HP, the temperature control system 1 is operated using parallel circuits C1 and C2. In the heat pump mode HP, a high temperature heat medium is supplied to the indoor heat exchanger 25, and a low temperature heat medium is supplied to the outdoor heat exchanger 23.
That is, the low-temperature heat medium flowing out of the evaporator 14 flows into the outdoor heat exchanger 23 via the second switching valve 32, as shown by the solid arrow. The heat medium that has absorbed heat from the outside air returns to the evaporator 14 via the first switching valve 31 and the evaporator flow rate adjustment valve 14V.
The refrigerant evaporates due to heat absorption 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 in the condenser 12 by releasing heat to the heat medium, and the temperature of the heat medium increases accordingly.

In the example shown in FIG. 1, by adjusting the flow rate with the evaporator flow rate adjustment valve 14V, the entire amount of the heat medium flowing from the first switching valve 31 toward the evaporator 14 does not flow into the evaporator bypass path 14A, but instead flows into the evaporator bypass path 14A. 14.

The high-temperature heat medium flowing out of the condenser 12 flows into the indoor heat exchanger 25 via the third switching valve 33, as shown by the dashed-dotted arrow. The heat medium that has warmed the interior of the vehicle compartment 8 returns to the condenser 12 via the first switching valve 31 and the condenser flow rate adjustment valve 12V.

In the example shown in FIG. 1, by adjusting the flow rate by the condenser flow rate adjustment valve 12V, the entire amount of the heat medium flowing from the first switching valve 31 toward the condenser 12 does not flow into the condenser bypass path 12A, but instead flows into the condenser bypass path 12A. 12.

By using outside air as part of the heat source, the heat pump mode HP can secure heating capacity while suppressing increases in power of the compressor 11, pumps 21, 22, etc.

[Explanation of heater mode]
Next, referring to FIG. 2, the heater mode HT, which is an operation mode using the series circuit CC, will be described. When the outside temperature is significantly lower than 0℃, for example, when the outside temperature drops to -20℃ or less, the amount of heat that can be absorbed from the outside air to the heat medium by the heat pump mode HP described above decreases, and the compressor The density of the refrigerant sucked into the compressor 11 decreases, and the power of the compressor 11 decreases. Even in such a case, heating operation can be performed using the compressor 11 as a heat source in the heater mode HT. In the heater mode HT, the power of the compressor 11 is used to heat the temperature-controlled object.

In the heater mode HT, for example, similar to a resistance heating type electric heater, heat of an amount corresponding to the supplied power is supplied to the temperature controlled object. Therefore, although it is called a "heater" mode, the name of the heater mode HT is not necessarily limited to this.
Note that the heater mode at startup HT0, which will be described later, is a mode that assumes transition to heater mode HT, so the same name as heater mode HT is used, but the name of heater mode at startup HT0 does not necessarily correspond to this. Not limited.

The specific flow of the heat medium in heater mode HT will be explained. In order to prevent heat radiation from the heat medium to the outside air, the heat medium is detoured from the outdoor heat exchanger 23 through the outdoor bypass path 24. At this time, the operation of the outdoor blower 23A may be stopped.
The control device 5 switches to the heater mode HT by sending commands to the first switching valve 31, the second switching valve 32, the evaporator flow rate adjustment valve 14V, the condenser flow rate adjustment valve 12V, the outdoor blower 23A, and the indoor blower 25A. A corresponding path is set in the heat medium circuit 20.

The heat medium that has absorbed heat from the refrigerant by the condenser 12 flows into the indoor heat exchanger 25 via the third switching valve 33 and is used to heat the interior of the vehicle 8. Then, the heat medium flowing out from the indoor heat exchanger 25 passes through the first switching valve 31 and the evaporator flow rate adjustment valve 14V, flows into at least the evaporator 14 among the evaporator 14 and the evaporator bypass path 14A, and flows into the refrigerant. Heat is radiated to.
The heat medium flowing out from the evaporator 14 flows into the outdoor bypass path 24 from the second switching valve 32, and is transferred from the first switching valve 31 to the condenser 12 between the first switching valve 31 and the condenser flow rate adjustment valve 12V. After joining the flow toward the refrigerant, the refrigerant flows into at least the condenser 12 and the condenser bypass path 12A, and absorbs heat from the refrigerant.

In the heater mode HT, the heat medium receives heat generated by the power of the compressor 11 from the refrigerant and conveys it to the temperature control target while flowing through the outdoor bypass path 24 avoiding heat radiation to the outside air. According to the heater mode HT, since the system is operated with no exchange of heat with the outside air, the interior of the vehicle interior 8 can be continuously heated regardless of the outside temperature.

[Explanation of mode selection]
Mode selection between the heat pump mode HP and the heater mode HT by the mode selection unit 50 will be explained.
The horizontal axis in FIG. 4(a) is the outside air temperature T, and the vertical axis is the heating capacity CP. In FIG. 4(a), the outside air temperature vs. heating capacity characteristic OH1 in the heat pump mode HP is shown by a solid line, and the outside air temperature vs. heating ability characteristic OH2 in the heater mode HT is shown by a dashed-dotted line. FIG. 4(a) shows correlation data DT between the characteristic OH1 and the characteristic OH2.

Here, the "heating capacity" corresponds to the heating capacity when the rotation speed of the compressor 11 is maximum (hereinafter referred to as maximum heating capacity). At this time, the rotational speed of the

pumps

21 and 22 also reaches its maximum. At the maximum heating capacity of the heat pump mode HP, the entire amount of the heat medium flowing from the first switching valve 31 toward the evaporator 14 flows into the evaporator 14, and the amount of heat medium flowing from the first switching valve 31 toward the condenser 12 flows into the evaporator 14. The entire amount flows into the condenser 12.
At the maximum heating capacity in heater mode HT, the entire amount of the heat medium flowing from the first switching valve 31 toward the evaporator 14 flows into the evaporator 14, and the heat medium flowing from the first switching valve 31 toward the condenser 12 The entire amount flows into the condenser 12.

According to the characteristic OH1, in the heat pump mode HP, the heating capacity CP gradually decreases as the outside air temperature T decreases. Further, according to the characteristic OH2, in the heater mode HT, the heating capacity CP is constant regardless of the outside temperature T.
Based on the characteristics OH1 and OH2, the line indicating the characteristic OH1 and the line indicating the characteristic OH2 intersect. The outside air temperature corresponding to the intersection X of these lines is referred to as the intersection outside air temperature _T.sub.X. A switching outside air temperature T _S is set at this intersection outside air temperature T _X.

The mode selection unit 50 selects the heat pump mode HP when the outside air temperature _T detected by the outside air temperature sensor 51 is higher than the outside air temperature T S for switching, and selects the heat pump mode HP for the outside air temperature T _S detected by the outside air temperature sensor 51. When the outside air temperature T is low, the heater mode HT is selected.
When an outside air temperature T higher than the switching outside air temperature T _S is detected, the heating capacity CP of the region R2 in the characteristic OH1 of the heat pump mode HP corresponding to the detected outside air temperature T is higher than the heating capacity of the heater mode HT. Higher than CP.
On the other hand, when an outside air temperature T lower than the switching outside air temperature _TS is detected, the heating capacity CP of the heater mode HT is higher than the heating capacity CP of the region R1 of the characteristic OH1 of the heat pump mode HP corresponding to the outside air temperature T. higher than
The control device 5 can set either the heat pump mode HP or the heater mode HT as the operation mode of the temperature control system 1 based on the determination of the outside air temperature T using the switching outside air temperature T _S as a threshold value.

Next, referring to Fig. 4(b), an example of a case where a mode is selected according to the air conditioning load L of the temperature adjustment system 1 will be described. As shown in Fig. 5, when the heat pump mode HP is selected based on the determination of the outside air temperature T described above (No in step S01), the mode selection unit 50 does not select a mode based on the following determination, but determines the selected mode to be the heat pump mode HP (step S02).
On the other hand, if the heater mode HT is selected based on the above-mentioned judgment of the outside air temperature T (first judgment) (Yes in step S01), that is, if the heating capacity CP of region R1 of characteristic OH1 of the heat pump mode HP corresponding to the detected outside air temperature T is inferior to the heating capacity CP of the heater mode HT, it is preferable to determine the operating mode according to the air conditioning load L by the second judgment described below (steps S03 to S05).

FIG. 4B shows L ₁ and L ₂ as an example of the air conditioning load L, which is the heating load of the temperature control system 1. L ₁ <L ₂ . Both of the air conditioning loads L ₁ and L ₂ are heating loads, and the heating loads become smaller as the outside temperature rises.
Here, the "air conditioning load" is defined by the following equation (1). The air temperature in the formula is strictly air enthalpy. Strictly speaking, the air volume in the formula is the mass flow rate.
Air conditioning load L = air volume Q × (target outlet air temperature T _T - suction air temperature T _I )…(1)

The air volume Q refers to the volumetric flow rate of air sent to the indoor heat exchanger 25 by the indoor blower 25A and the running of the vehicle. The air volume Q can be obtained from, for example, the number of stages set by the occupant or the number of stages set by the temperature control system 1, and the blowout mode (Face/Foot/Defogger, etc.).
The target blown air temperature T _T is the target temperature of the air blown into the vehicle interior 8 from the HVAC unit U, and is set from the target temperature of the air within the vehicle interior 8 . The target blown air temperature T _T is calculated by the room temperature sensor 52 or the like.
The suction air temperature T _I refers to the temperature of air introduced into the indoor heat exchanger 25 by the indoor blower 25A and the running of the vehicle. The intake air temperature _TI corresponds to the room temperature detected by the room temperature sensor 52 when the inside air circulation is set, and corresponds to the outside temperature detected by the outside temperature sensor 51 when the outside air intake is set. Equivalent to.
When the outside temperature is significantly below 0°C, the air conditioning load is high because the difference ΔT between T _T and T _I is large.

It is preferable that the mode selection unit 50 calculates the air conditioning load L using the above equation and sets the switching outside air temperature _TSL according to the air conditioning load L. For example, if the air conditioning load is _L1 , the switching outside temperature _TSL is set to the temperature _T1 corresponding to the intersection X1 of the air conditioning load _L1 and the outside temperature-heating capacity characteristic OH1 of the heat pump mode HP. Further, if the air conditioning load is L ₂ , the switching outside temperature T _SL is set to the temperature T ₂ corresponding to the intersection point X 2 of the air conditioning load L ₁ and the outside temperature-heating capacity characteristic OH1 of the heat pump mode HP.
The mode selection unit 50 selects the heat pump mode HP (step S04) when the outside air temperature T is high (No in step S03) with respect to the switching outside air temperature _TSL set according to the air conditioning load L, and selects the switching outside air temperature If the outside air temperature T is lower than _TSL (Yes in step S03), heater mode HT is selected (step S05).

For example, when the outside air temperature T is _T1 and the air conditioning load is _L1 , _TSL =T (No in step S03), so the heat pump mode HP is selected (step S04).
On the other hand, if the outside air temperature T is also _T1 and the air conditioning load is _L2 , which is larger than _L1 , _TSL >T (Yes in step S03), so the heater mode HT is selected. (Step S05).

When the outside air temperature T is _T2 and the air conditioning load is _L1 , _TSL <T (No in step S03), so the heat pump mode HP is selected (step S04).
Also, when the outside air temperature T is _T2 and the air conditioning load is _L2 , which is larger than _L1 , _TSL = T (No in step S03), so the heat pump mode HP is selected. (Step S04). However, even if the outside temperature T remains unchanged at _T2 , if the air conditioning load becomes higher than _L2 , _TSL >T (Yes in step S03), so the heater mode HT is selected (step S05). )

The control device 5 can set either the heat pump mode HP or the heater mode HT as the operation mode of the temperature control system 1 based on the determination of the outside air temperature T using the switching outside air temperature _TSL as a threshold value.

[Main effects of this embodiment]

The mode selection unit 50 determines mode selection using the switching outside air temperature T _S set based on the correlation data DT of the outside air temperature-heating capacity characteristics OH1 and OH2 of the heat pump mode HP and the heater mode HT, respectively, as a threshold. be able to. Then, the heat pump mode HP or the heater mode HT can be appropriately selected based on the heating capacity CP which depends on the outside air temperature T.
When the air conditioning load L is high, such as when the outside air temperature T is significantly below 0°C, the heater mode HT, which operates using the compressor 11 as the heat source, is selected, so that capacity shortages do not occur regardless of the outside air temperature T. It is possible to heat the object without heating.
Furthermore, even if the heater mode HT is more suitable than the heat pump mode HP in terms of the amount of heat input into the heat medium that exchanges heat with the condenser 12, the characteristics of the outside air temperature T and the heating capacity CP Based on OH1 and OH2, it is possible to select a heat pump mode HP that can be operated with low power consumption by absorbing heat from the outside air. Then, if the heating capacity obtained by the heat pump mode HP is sufficient for the required heating capacity, the heater mode HT, which obtains the necessary amount of heat by supplying power to the compressor 11, is not selected, resulting in economical operation. becomes possible.

Furthermore, regarding the region R1 where the heating capacity CP of the heat pump mode _HP is inferior to the heating capacity CP of the heater mode _HT , the intersection point (X1, ), an operating mode sufficient for the air conditioning load L can be selected from the heat pump mode HP and the heater mode _HT using the switching outside air temperature TSL set to a temperature corresponding to the temperature. By appropriately selecting the mode based on the air conditioning load L in this way, even more economical operation becomes possible.

In addition to the above, in the heater mode HT using the series circuit CC, since the condenser 12 and the evaporator 14 are connected in series, the heat medium flows in parallel to the condenser 12 and the evaporator 14. The temperature of the heat medium flowing out from the condenser 12 can be raised more quickly than in the case where the heat medium flows out from the condenser 12. Furthermore, since the amount of heat medium circulated through the indoor heat exchanger 25 is large, the amount of heat exchanged between the heat medium and the air becomes large.

Furthermore, in the heater mode HT, the heat medium that has passed through the condenser 12 and the indoor heat exchanger 25 is radiated to the refrigerant by the evaporator 14, so that the low pressure in the refrigerant circuit 10 increases compared to the heat pump mode HP. As the density of the refrigerant sucked into the compressor 11 increases accordingly, the circulating flow rate of the refrigerant increases. Since the heat exchange capacity is improved by increasing the refrigerant circulation flow rate, and the heating capacity can be improved, the temperature inside the vehicle compartment 8 can be brought to the target temperature quickly.

According to the temperature control system 1, by providing at least the heater mode HT, even in situations where it is difficult to secure a heat source due to low outside temperature, heating can be performed while supplying the power necessary for securing the heat source to the compressor 11, etc. ability can be guaranteed.

[First modification]
As shown in FIG. 6, the switching outside air temperature T _S may be set to be shifted to a lower temperature side than the intersection outside air temperature T _X. In this case, if the mode is selected based only on the first determination (step S01) described above, when the outside air temperature T is higher than the switching outside air temperature T _S , the heating capacity CP is inferior to the heater mode HT. Heat pump mode HP may be selected.
However, since the heating capacity CP of the characteristics OH1 and OH2 is the maximum heating capacity, the heating capacity necessary for the actual air conditioning load L is not insufficient in most cases. Therefore, by setting the switching outside air temperature T _S to _an outside air temperature that is lower by a predetermined temperature difference Δx than the intersection outside air temperature T It can be operated economically.

Furthermore, the switching outside air temperature T _S can also be set to an outside air temperature that is lower by the temperature difference Δx' from the intersection point outside air temperature T _X to the intersection point X _max based on the maximum air conditioning load (T _S ′). The intersection point X _max is the intersection point between the maximum air conditioning load L _max assuming outside air introduction and the maximum air volume, and the characteristic OH1.

[Second modification]
The temperature control system 1 of the embodiment described above may include a startup heater mode HT0 as a startup heater mode shown in FIG. 7 .

For example, assuming a case where the temperature control system 1 is started after the vehicle has stopped for a long time, the startup heater mode HT0 and the heater mode HT will be explained. After starting the temperature control system 1, it is preferable that the control device 5 implements the startup heater mode HT0 prior to the heater mode HT. By doing so, heating operation can be started earlier.

If the outside temperature is significantly lower than 0° C. when the temperature control system 1 is started after the vehicle has stopped for a long time, the temperature of the heat medium is also low like the outside temperature. Therefore, immediately after the temperature control system 1 is started, the low pressure of the refrigerant circuit 10 decreases as the refrigerant is cooled by the heat medium, and the evaporation temperature of the refrigerant becomes lower than the outside air temperature. Therefore, when the temperature control system 1 is started, the startup heater mode HT0 gives priority to heating the passenger compartment 8 and transfers the heat absorbed from the outside air to the heat medium by the outdoor heat exchanger 23 to the refrigerant. It is better to warm up the refrigerant. Thereafter, the low pressure of the refrigerant circuit 10 rises to a predetermined value, and the refrigerant circuit 10 operates steadily, making it possible to heat the temperature-controlled object with the heat extracted from the power of the compressor 11 into the heat medium. It is better to switch to mode HT.

[Explanation of heater mode at startup]
With reference to FIG. 7, the action of the startup heater mode HT0 using the series circuit CC will be described along with the specific flow of the heat medium. In the startup heater mode HT0, the heat medium is caused to flow into the outdoor heat exchanger 23 in order for the outdoor heat exchanger 23 to absorb heat from the outside air to the heat medium. In addition, in order to give priority to heating the refrigerant over heating the interior of the vehicle compartment 8, the heat medium is not allowed to flow into the condenser 12, but is detoured to the condenser bypass path 12A, thereby preventing heat radiation of the refrigerant to the heat medium. . Then, in the evaporator 14, heat is radiated from the heat medium to the refrigerant.
Furthermore, in order to suppress heat exchange between the air and the heat medium in the indoor heat exchanger 25, it is preferable to stop the operation of the indoor blower 25A.

In the startup heater mode HT0, the heat medium is detoured from the condenser 12, so the pressure loss of the heat medium is smaller than when the heat medium flows through the condenser 12.

The heat medium flowing out from the evaporator 14 flows into the outdoor heat exchanger 23 via the second switching valve 32 and absorbs heat from the outside air. In FIG. 7, the heat medium whose temperature has increased due to heat absorption from the outside air is indicated by a dashed line. The heat medium flowing out from the outdoor heat exchanger 23 bypasses the condenser 12 by flowing into the condenser bypass path 12A via the first switching valve 31 and the condenser flow rate adjustment valve 12V. The heat medium flowing out from the condenser bypass path 12A flows into the indoor heat exchanger 25 via the third switching valve 33. However, since the indoor blower 25A is stopped, heat exchange between the heat medium in the indoor heat exchanger 25 and unconditioned cold air is suppressed. The heat medium flowing out of the indoor heat exchanger 25 returns to the evaporator 14 via the first switching valve 31 and the evaporator flow path adjustment valve 14V. Then, the heat is radiated to the refrigerant by the evaporator 14 and flows out from the evaporator 14 as a low-temperature heat medium.

The area extends from the outlet of the outdoor heat exchanger 23 to the inlet of the evaporator 14 via the condenser bypass path 12A and the indoor heat exchanger 25, and exchanges heat between the heat medium and the refrigerant, and between the heat medium and air. Transfer of heat between the two is suppressed. The heat medium that has absorbed heat from the outside air passes through the condenser bypass path 12A and the indoor heat exchanger 25, and carries the heat to the evaporator 14 through which the refrigerant flows.

While the vehicle is stopped in a state where the outside temperature is very low, below freezing, the respective temperatures of the heat medium and the refrigerant drop to the same level as the outside temperature. Therefore, the compressor 11 is started by starting the temperature control system 1, and immediately after the refrigeration cycle is started, the refrigerant cools the heat medium. However, according to the startup heater mode HT0, by continuously transmitting the heat absorbed by the heat medium from the outside air to the refrigerant, the low pressure of the refrigerant circuit 10 gradually increases, and the evaporation temperature also increases. In the process, the temperature of the heat medium that exchanges heat with the refrigerant also rises.

If the temperature of the heat medium exceeds the outside air temperature, heat absorption from the outside air becomes insufficient, so the control device 5 preferably shifts the temperature control system 1 to the heater mode HT when the heat medium approaches the outside air temperature. For example, it is preferable to shift to the heater mode HT when the temperature of the heat medium exceeds a threshold value _t3 , which is lower by a predetermined temperature difference α than the outside air temperature (for example, −20° C.). The difference between the outside temperature and the threshold value is determined by the temperature difference corresponding to the time required for the flow of the heat medium to switch in response to a command to switch the operating mode.

When the heating operation is selected by the occupant's operation or by the temperature control system 1, the control device 5 causes the mode selection unit 50 to select the heat pump mode HP or the heater mode based on the comparison between the switching outside air temperature _TS and the outside air temperature T. HT can be selected. Furthermore, if the outside air temperature T is higher than the threshold value t ₂ (eg -15° C.) lower than the switching outside air temperature T _S , the control device ₅ selects the heat pump mode HP and If the temperature is low, startup heater mode HT0 can be selected.

If the detected outside air temperature T is lower than the switching outside air temperature _TS and immediately after the temperature control system 1 is started, the control device 5 switches the heater on without comparing the outside air temperature T and the threshold value _t2 . The startup heater mode HT0 can be selected prior to the mode HT. Alternatively, immediately after startup when the outside air temperature T is lower than the switching outside air temperature _TS , first select the heater mode HT, and apply a predetermined threshold to the temperature of the heat medium or refrigerant detected at that time. Then, it may be determined whether to continue the heater mode HT or switch to the startup heater mode HT0.

When the startup heater mode HT0 is performed prior to the heater mode HT, the control device 5 waits until the refrigerant circuit 10 is in a steady state while operating the temperature control system 1 in the startup heater mode HT0, for example. When the temperature of the heat medium exceeds a predetermined threshold value _t3 , the operation mode can be switched from the startup heater mode HT0 for startup to the steady state heater mode HT. The threshold value is not limited to the temperature of the heat medium or refrigerant, but it is also possible to use a physical quantity such as a pressure that indicates a state similar to the state of the heat medium or refrigerant indicated by the temperature threshold.
After switching from the startup heater mode HT0 to the heater mode HT, it is preferable to gradually increase the flow rate of the heat medium flowing into the condenser 12 using the condenser flow rate adjustment valve 12V.

In addition to the above, it is possible to select the configurations mentioned in the above embodiments or to change them to other configurations as appropriate.
In addition to or in place of the indoor heat exchanger 25 as a temperature control device, the temperature control system 1 may include other temperature control devices such as a battery device. In that case, the heat medium circuit 20 includes a path for cooling or heating other temperature control devices with the heat medium.

[Additional notes]
From the above disclosure, the configuration described below can be understood.
[1] A temperature control system for a vehicle,
A refrigerant circuit (10) including a compressor 11, a high-pressure side heat exchanger (12), a pressure reducing section (13), and a low-pressure side heat exchanger (14), and configured to allow refrigerant to circulate according to a refrigeration cycle;
A heat medium circuit (20) configured to allow circulation of a heat medium that transfers heat to and receives heat from the refrigerant,
The heat medium circuit (20) includes:
the high-pressure side heat exchanger (12) for exchanging heat between the refrigerant and the heat medium;
the low pressure side heat exchanger (14) for exchanging heat between the refrigerant and the heat medium;
A first pump (21) and a second pump (22), both of which are configured to be able to pump the heat medium;
an outdoor heat exchanger (23) that exchanges heat between outside air and the heat medium;
A temperature control device (25) corresponding to a temperature control object heated or cooled by the heat medium or used for heating or cooling the temperature control object;
an outdoor bypass path (24) that detours the heat medium from the outdoor heat exchanger (23),
The temperature control system has the following operating modes:
a low-pressure side circuit (C1) in which the heat medium circulates through the low-pressure side heat exchanger (14) and the outdoor heat exchanger (23) by the first pump (21); and the high-pressure side heat exchanger (12). and a heat pump mode (HP) in which a high pressure side circuit (C2) in which the heat medium circulates through the temperature control device (25) by the second pump (22) is formed;
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 through the outdoor bypass path (24). a compressor heat source mode (HT) flowing into the high pressure side heat exchanger (12);
a mode selection unit (50) configured to be able to select the heat pump mode (HP) or the compressor heat source mode;
An outside temperature sensor (51) that detects outside air temperature,
The mode selection section (50) includes:
The intersection point outside air temperature (T X ) corresponding to the intersection point ( _X ) of the outside air temperature-heating capacity characteristics (OH1, OH2) of each of the heat pump mode (HP) and the compressor heat source mode (HT), or the intersection point outside air _The heat pump _mode ₍ HP), and when the outside air temperature (T) is low, the compressor heat source mode (HT) is selected;
Vehicle temperature control system.

[2] The mode selection unit (50) selects a region (R1) in which the heating capacity (CP) is inferior to the compressor heat source mode (HT) in the outside air temperature-heating capacity characteristic (OH1) of the heat pump mode (HP). ), the switching outside air temperature (T _SL ) is configured to be settable according to the heating load (L ₁ , L ₂ ).
[1] The vehicle temperature control system according to item [1].

[3] In the outside air temperature-heating capacity characteristic (OH1) of the heat pump mode (HP), as the outside air temperature (T) decreases, the heating capacity (CP) decreases,
With respect to the switching outside temperature (T _SL ) corresponding to the intersection (X1, X2) of the heating load (L ₁ , L ₂ ) and the outside temperature-heating capacity characteristic of the heat pump mode (HP), the outside air temperature (T) is high, the heat pump mode (HP) is selected, and when the outside air temperature (T) is low, the compressor heat source mode (HT) is selectable;
[2] The vehicle temperature control system according to item [2].

[4] A high-pressure side bypass path (12A) that detours the heat medium from the high-pressure side heat exchanger (12);
A high-pressure side flow rate adjustment valve (12V) configured to be able to adjust the flow rate ratio of the heat medium between the high-pressure side heat exchanger (12) and the high-pressure side bypass path,
As the driving mode,
The heat medium flowing out from the high pressure side heat exchanger (12) flows into the low pressure side heat exchanger (14), further passes through the outdoor heat exchanger (23), and then flows into the high pressure side heat exchanger (12). ) and a start-up compressor heat source mode (HT0) flowing into at least the high pressure side bypass path (12A) among the high pressure side bypass path (12A),
The vehicle temperature control system according to any one of [1] to [3].

[5] The start-up compressor heat source mode (HT0) causes the heat medium flowing out of the low-pressure side heat exchanger (14) to flow into the outdoor heat exchanger (23).
[6] A temperature control method using a vehicle temperature control system,
The temperature control system is
A refrigerant circuit (10) including a compressor 11, a high-pressure side heat exchanger (12), a pressure reduction section (13), and a low-pressure side heat exchanger (14), and configured to allow refrigerant to circulate according to a refrigeration cycle;
a heat medium circuit (20) configured to allow circulation of a heat medium that transfers heat to and receives heat from the refrigerant;
The heat medium circuit (20) includes:
the high-pressure side heat exchanger (12) for exchanging heat between the refrigerant and the heat medium;
the low pressure side heat exchanger (14) for exchanging heat between the refrigerant and the heat medium;
A first pump (21) and a second pump (22), both of which are configured to be able to pump the heat medium;
an outdoor heat exchanger (23) that exchanges heat between outside air and the heat medium;
A temperature control device (25) corresponding to a temperature control object heated or cooled by the heat medium or used for heating or cooling the temperature control object;
an outdoor bypass path (24) that detours the heat medium from the outdoor heat exchanger (23);
including;
The temperature control method is
a low-pressure side circuit (C1) in which the heat medium circulates through the low-pressure side heat exchanger (14) and the outdoor heat exchanger (23) by the first pump (21); and the high-pressure side heat exchanger (12). and a heat pump mode (HP) in which a high pressure side circuit (C2) in which the heat medium circulates through the temperature control device (25) by the second pump (22) is formed;
The heat medium flowing out from 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 through the outdoor bypass path (24). In selecting one of the compressor heat source mode (HT) flowing into the high pressure side heat exchanger (12),
The intersection point outside air temperature (T x ) corresponding to the intersection point ( _X ) of the outside air temperature-heating capacity characteristics (OH1, OH2) of each of the heat pump mode (HP) and the compressor heat source mode (HT), or the intersection point outside air When the detected outside air temperature (T) is higher than the outside air temperature (T _S , T _SL ) which is set to a lower temperature than the outside air temperature (T _X ), the heat pump mode (HP) is selected and the outside air If the temperature (T) is low, select the compressor heat source mode (HT);
Vehicle temperature control method.

1 Temperature control system 5 Control device 8 Compartment 10 Refrigerant circuit 11 Compressor 12 Condenser 12A Condenser bypass path 12V Condenser flow rate adjustment valve 13 Expansion valve (pressure reducing section)
14 Evaporator 14A Evaporator bypass path 14V Evaporator flow rate adjustment valve 20 Heat medium circuit 21 First pump 22 Second pump 23 Outdoor heat exchanger 23A Outdoor blower 24 Outdoor bypass path 25 Indoor heat exchanger 25A Indoor blower 31 First switching Valve 32 Second switching valve 33 Third switching valve 50 Mode selection section 51 Outside temperature sensor 52 Room temperature sensor 501 Memory 502 Arithmetic section 503 Storage section 504 Input/output section C1 Low pressure side circuit C2 High pressure side circuit CC Series circuit CP Heating capacity DT Correlation Data R1, R2 Area HP Heat pump mode HT Heater mode (compressor heat source mode)
HT0 Start-up heater mode (start-up compressor heat source mode)
L, L ₁ , L ₂ Air conditioning load OH1, OH2 Outside air temperature - heating capacity characteristics T, T ₁ , T ₂ Outside air temperature T _S , T _SL switching outside air temperature T _X Intersection outside air temperature U Unit X Intersection Δx Temperature difference

Claims

A temperature control system for a vehicle,
A refrigerant circuit including a compressor, a high-pressure side heat exchanger, a pressure reduction section, and a low-pressure side heat exchanger, and configured to allow refrigerant to circulate according to a refrigeration cycle;
a heat medium circuit configured to allow circulation of a heat medium that transfers heat to and receives heat from the refrigerant;
The heat medium circuit is
the high-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium;
the low-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium;
a first pump and a second pump, both of which are configured to be able to pump the heat medium;
an outdoor heat exchanger that exchanges heat between outside air and the heat medium;
A temperature control device corresponding to a temperature control object heated or cooled by the heat medium or used for heating or cooling the temperature control object;
an outdoor bypass path that detours the heat medium from the outdoor heat exchanger,
The temperature control system has the following operating modes:
a low-pressure side circuit in which the heat medium circulates through the low-pressure side heat exchanger and the outdoor heat exchanger by the first pump; and a low-pressure side circuit in which the heat medium circulates through the high-pressure side heat exchanger and the temperature control device by the second pump. A heat pump mode in which a circulating high pressure side circuit is formed;
The heat medium flowing out from the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device, and further passes through the outdoor bypass path and flows into the high-pressure side heat exchanger. In addition to being equipped with a machine heat source mode,
a mode selection unit configured to be able to select the heat pump mode or the compressor heat source mode;
Equipped with an outside temperature sensor that detects outside air temperature,
The mode selection section includes:
The switching outside air temperature is set to an intersection outside temperature corresponding to the intersection of the outside air temperature-heating capacity characteristics of the heat pump mode and the compressor heat source mode, or is set to a temperature lower than the intersection outside air temperature. On the other hand, when the outside air temperature detected by the outside air temperature sensor is high, the heat pump mode is selected, and when the outside air temperature is low, the compressor heat source mode is selected.
Vehicle temperature control system.
The mode selection unit is configured to be able to set the switching outside air temperature in accordance with the heating load in a region where the heating ability is inferior to the compressor heat source mode in the outside air temperature-heating ability characteristic of the heat pump mode.
The vehicle temperature control system according to claim 1.
In the outside air temperature-heating capacity characteristic of the heat pump mode, as the outside air temperature decreases, the heating ability decreases,
The mode selection unit selects the heat pump mode when the outside air temperature is high with respect to the switching outside air temperature corresponding to the intersection of the heating load and the outside air temperature-heating capacity characteristic of the heat pump mode, and selects the heat pump mode when the outside air temperature is high. configured to select the compressor heat source mode when the temperature is low;
The vehicle temperature control system according to claim 2.
a high-pressure side bypass path that detours the heat medium from the high-pressure side heat exchanger;
a high-pressure side flow rate adjustment valve configured to be able to adjust a flow rate ratio of the heat medium between the high-pressure side heat exchanger and the high-pressure side bypass path;
As the driving mode,
a start-up compressor heat source mode in which the heat medium flowing out of the low-pressure side heat exchanger flows into the outdoor heat exchanger and further flows into the high-pressure side bypass path;
The vehicle temperature control system according to any one of claims 1 to 3.
an indoor heat exchanger for exchanging heat between the air sent and the heat medium;
In the start-up compressor heat source mode, the heat medium flowing through the high-pressure side bypass path is returned to the low-pressure side heat exchanger after flowing into the outdoor heat exchanger.
The vehicle temperature control system according to claim 4.
A temperature control method using a vehicle temperature control system,
The temperature control system is
A refrigerant circuit including a compressor, a high-pressure side heat exchanger, a pressure reduction section, and a low-pressure side heat exchanger, and configured to allow refrigerant to circulate according to a refrigeration cycle;
a heat medium circuit configured to allow circulation of a heat medium that transfers heat to and receives heat from the refrigerant;
The heat medium circuit is
the high-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium;
the low-pressure side heat exchanger that exchanges heat between the refrigerant and the heat medium;
a first pump and a second pump, both of which are configured to be able to pump the heat medium;
an outdoor heat exchanger that exchanges heat between outside air and the heat medium;
A temperature control device corresponding to a temperature control object heated or cooled by the heat medium or used for heating or cooling the temperature control object;
an outdoor bypass path that detours the heat medium from the outdoor heat exchanger,
The temperature control method is
a low-pressure side circuit in which the heat medium circulates through the low-pressure side heat exchanger and the outdoor heat exchanger by the first pump; and a low-pressure side circuit in which the heat medium circulates through the high-pressure side heat exchanger and the temperature control device by the second pump. A heat pump mode in which a circulating high pressure side circuit is formed;
The heat medium flowing out from the high-pressure side heat exchanger flows into the low-pressure side heat exchanger via the temperature control device, and further passes through the outdoor bypass path and flows into the high-pressure side heat exchanger. When selecting one of the machine heat source modes,
Detected for an intersection outside temperature corresponding to the intersection of the outside air temperature-heating capacity characteristics of the heat pump mode and the compressor heat source mode, or a switching outside air temperature that is set to a temperature lower than the intersection outside air temperature. When the outside air temperature is high, the heat pump mode is selected, and when the outside air temperature is low, the compressor heat source mode is selected.
Vehicle temperature control method.