JP6964049B2 - Heat pump type cold water air conditioner - Google Patents

Description

The present invention relates to a heat pump type chilled water cooling device that supplies a cooled circulating liquid to an air conditioning terminal to perform a cooling operation.

Conventionally, in this type of thing, as described in Patent Document 1, the circulating liquid cooled by the load side heat exchanger of the heat pump type heat source machine is supplied to the air conditioning terminal, and the cooling operation is performed. ..

In this conventional technique, the operation of the heat pump type heat source machine is controlled by so-called return temperature control. That is, the heat pump type heat source machine is controlled so that the temperature of the circulating liquid flowing from the air conditioning terminal to the load side heat exchanger becomes the target return temperature. In this return temperature control, the forward temperature of the circulating fluid flowing out from the load side heat exchanger to the air conditioning terminal changes according to the load, and when the load is low, the forward temperature can be raised during the cooling operation. The feature is that the efficiency of the heat pump type heat source machine can be improved.

Japanese Unexamined Patent Publication No. 2017-1676773

On the other hand, as a control method of the heat pump type heat source machine different from the return temperature control, there is a so-called forward degree control. In this case, the heat pump type heat source machine is controlled so that the forward temperature of the circulating liquid flowing out from the load side heat exchanger to the air conditioning terminal becomes the target forward temperature. This forward temperature control has a feature that it is easy to maintain the output of the air conditioning terminal because the supply temperature to the air conditioning terminal becomes constant.

Here, there are various types of air-conditioning terminals, and depending on the type of the air-conditioning terminal, when it is preferable to perform the forward temperature control or the return temperature control during the cooling operation due to its characteristics. May be preferable.

For example, when the fan coil unit, which is a type of forced convection terminal, performs cooling operation, the indoor air is circulated by the blower fan, so that the humidity in the room is dehumidified to some extent evenly (that is, latent heat treatment) at the time of high load at the beginning of operation. ) After that, the operation becomes stable. Therefore, even if the return temperature control is performed with the main purpose of improving efficiency, it is unlikely that comfort will be impaired by high humidity.

On the other hand, for example, when a cold / hot water panel, which is a kind of radiant terminal, performs cooling operation, the compressor is driven in a high rotation speed range and the output is large at the time of high load at the initial stage of operation, and the humidity around the panel is large. Can be dehumidified to some extent (that is, latent heat treatment), but when the panel itself cools to some extent, the number of revolutions of the compressor is reduced even if the temperature in the room is not completely lowered. In this case, if the return temperature control is performed, the temperature of the circulating fluid supplied to the panel will gradually increase at the timing when the panel itself has cooled to some extent (even if the temperature in the room has not yet decreased). As a result, the temperature inside the room is less likely to drop, and as a result, the humidity inside the room does not drop completely, leading to an unpleasant situation. Therefore, when the cold / hot water panel performs the cooling operation, there are situations where it is better to control the forward temperature in order to reduce the humidity in the room.

In the above-mentioned prior art, the point of properly using the return temperature control and the forward temperature control according to the type of the air-conditioning terminal as described above is not particularly considered, and there is room for improvement.

In order to solve the above problems, in the first aspect of the present invention, a compressor for compressing a refrigerant, a load-side heat exchanger for heat exchange between a circulating liquid and the refrigerant, a decompression means, and a heat source-side heat exchanger. A heat pump type heat source machine having A circulation circuit formed by connecting in a ring shape with a pipe to circulate the circulating fluid, a traveling temperature determining means for determining the outgoing temperature of the circulating fluid flowing out from the load side heat exchanger to the air conditioning terminal, and the air conditioning terminal. The air conditioner terminal is provided with a return temperature determining means for determining the return temperature of the circulating fluid flowing into the load side heat exchanger from the air, and the circulating fluid cooled by the heat pump type heat source machine is driven by the circulation pump. In the heat pump type chilled water cooling device that supplies the heat to the heat pump type to perform the cooling operation, the heat pump type heat source machine is controlled so that the forward temperature determined by the forward temperature determining means becomes the target forward temperature, or the forward temperature control or the above. The return temperature control that controls the heat pump type heat source machine so that the return temperature determined by the return temperature determining means becomes the target return temperature is executed, and the rotation speed of the compressor is increased or decreased according to the magnitude of the load. The control device is provided with a control device for determining the type of the air-conditioning terminal to be operated based on the operation request of the air-conditioning terminal, and the terminal determination means is used during the cooling operation. When it is determined that the radiation type terminal is operated as the air conditioning terminal, the control device executes the return temperature control if the rotation speed of the compressor is in the preset high rotation speed range, and the compressor of the compressor. If the rotation speed is in the preset medium rotation speed range, the forward temperature control is executed, and if the rotation speed of the compressor is in the preset low rotation speed range, the return temperature control is executed, and the terminal. When the determination means determines that a terminal other than the radiation type terminal is operated as the air conditioning terminal, the control device shall execute the return temperature control.

According to claim 1 of the present invention, when the radiation type terminal is operated as the air conditioner terminal during the cooling operation, the control device returns if the compressor rotation speed is in the preset high rotation temperature range. Temperature control is executed, and if the compressor rotation speed is in the preset medium rotation speed range, forward temperature control is executed, and if the compressor rotation speed is in the preset low rotation speed range, return temperature control is performed. When a device other than the radiant terminal is operated as the air-conditioning terminal, the control device shall execute the return temperature control. Of the return temperature controls, the optimum control can be executed.

In particular, when a radiant terminal is operated as an air-conditioning terminal, the control device executes return temperature control if the compressor rotation speed is in a preset high rotation speed range, so that the compressor rotates at a high speed. When driving in several ranges, the output is large and the temperature of the circulating fluid supplied to the radiant terminal tends to decrease, and the moisture around the radiant terminal in the air-conditioned space is dehumidified to some extent (that is, latent heat treatment). At the same time, it is possible to improve the efficiency when the rotation speed of the compressor decreases in the high rotation speed range as the load decreases. If the compressor rotation speed is in the preset medium rotation speed range, the radiant terminal itself is cooled to some extent by executing the forward temperature control, and the temperature around the radiant terminal becomes stable. When the compressor is driven in the medium rotation speed range under load, the temperature supplied to the radiating terminal becomes the target temperature, which is kept constant at a low temperature, so that the temperature of the air-conditioned space is surely lowered. At the same time, it is possible to reduce the humidity of the air-conditioned space and improve the comfort without stabilizing the air-conditioned space in a high humidity state. Furthermore, if the compressor rotation speed is in the preset low rotation speed range, the return temperature control is executed to be air-conditioned when the compressor is driven in the low rotation speed range at low load. Since the temperature and humidity environment of the space is already in place, the efficiency can be improved by the return temperature control that emphasizes efficiency. In addition, when a forced convection terminal other than a radiant terminal is operated as an air-conditioned terminal, for example, when a forced convection terminal is operated, the air in the air-conditioned space is circulated by a blower fan, so that the humidity in the air-conditioned space is made uniform to some extent at the time of high load at the initial stage of operation. After dehumidifying (that is, latent heat treatment), the operation becomes stable, so it is unlikely that comfort will be hindered by high humidity, so efficiency can be improved by returning temperature control that emphasizes efficiency. be.

The figure which shows the whole schematic structure of the structural example of the heat pump type chilled water cooling apparatus of one Embodiment of this invention. The figure which shows the appearance structure of the main remote control device. The figure which represented the refrigerating cycle in the cooling operation of an outdoor unit schematically. A functional configuration diagram showing the main functions of the outdoor unit control unit. The figure which shows the correspondence relationship between the compressor rotation speed and the recommended control mode for each type of an air-conditioning terminal. The flowchart which shows the control procedure which the compressor control part and the expansion valve control part execute at the time of a cooling operation. A time chart showing an example of cooling operation behavior in the configuration example shown in FIG. Other functional configuration diagrams showing the main functions of the outdoor unit control unit.

Next, an embodiment of the present invention will be described with reference to the drawings.

<Configuration of an example of a heat pump type chilled water air conditioner>
FIG. 1 shows an overall schematic configuration of a configuration example of the heat pump device of the present embodiment. In FIG. 1, the heat pump device 100 is connected to an outdoor unit 1 as a heat pump type heat source machine installed outdoors and the outdoor unit 1 via a cold / hot water outflow pipe 2 and a cold / hot water return pipe 3 indoors. At least one air-conditioning terminal installed in, in this example, a radiant terminal having a drain water treatment function (however, it also has a heat absorption / dissipation function by natural convection), a hot / cold water panel 51, and a forced water having a drain water treatment function. It has two with a fan coil unit 52 which is a convection type terminal. The heat pump device 100 can function as a heat pump type hot water heating device and a heat pump type chilled water cooling device, but in this embodiment, components and operations when mainly used as a heat pump type chilled water cooling device. Will be described.

The cold / hot water panel 51 absorbs heat from the air in the room which is the air-conditioned space by using the circulating liquid cooled by the outdoor unit 1 to cool the room.

The fan coil unit 52 contains a heat exchanger (not shown), a blower fan (not shown), a thermal valve V3, an indoor temperature sensor (not shown) for detecting the indoor temperature, and a fan coil unit. It includes a water temperature sensor (not shown) that detects the temperature of the circulating fluid flowing through the 52, a terminal control unit 29, and the like. The terminal control unit 29 receives a signal from the indoor temperature sensor inside the fan coil unit 52 and a signal from the terminal remote controller RC (described later), and controls the drive of the blower fan and the thermal valve V3. As a result, the fan coil unit 52 allows the circulating liquid cooled by the outdoor unit 1 to pass through the heat exchanger inside, and drives the blower fan to exchange heat with the indoor air to cool the room. I do.

The cold / hot water panel 51 is arranged in the A room of the A room and the B room, and the fan coil unit 52 is arranged in the B room. Then, one outbound header 91 is provided in the middle of the cold / hot water outflow pipe 2 extending from the outdoor unit 1, and the portion of the cold / hot water outbound pipe 2 upstream of the outbound header 91 is used as one common outbound pipe 2A. It is configured and the circulating fluid from the outdoor unit 1 is supplied. The portion 2B of the cold / hot water outflow pipe 2 downstream from the outbound header 91 is a plurality of (two in this example) outbound pipes, that is, the outbound pipe 2B1 to the cold / hot water panel 51 and the fan coil unit. It is connected to the outgoing header 91 in a form of branching to the outgoing pipe 2B2 to 52.

Similarly, one return header 92 is provided in the middle of the cold / hot water return pipe 3 extending to the outdoor unit 1, and a plurality of cold / hot water return pipes 3 upstream of the return header 92 (3B). In this example, it is divided into two) return pipes, that is, a return pipe 3B1 from the hot / cold water panel 51 and a return pipe 3B2 from the fan coil unit 52. The portion of the cold / hot water return pipe 3 downstream of the return header 92 is configured as one common return pipe 3A (that is, the branched return pipes 3B1 and 3B2 are concentrated on the upstream side of the common return pipe 3A. The circulating fluid introduced through the return pipes 3B1 and 3B2 (which is connected to the return header 92) is returned to the outdoor unit 1.

The outgoing pipe 2B1 to the cold / hot water panel 51 is provided with a thermal valve V1 capable of opening and closing the outgoing pipe 2B1 by a drive signal from the thermal valve controller CV. In this example, the main remote controller RM as a setting operation means for performing the cooling operation operation of the cold / hot water panel 51 is provided in the room A. Further, in this example, a wireless terminal remote controller RC for remotely controlling the fan coil unit 52 is provided in the B chamber. The main remote controller RM corresponds to an operating means.

The main remote controller RM outputs a control signal SS1 in response to a user operation. This control signal SS1 is input to the outdoor unit control unit CU (described later) that controls the outdoor unit 1, thereby controlling the flow rate, temperature, and the like of the cold and hot water supplied to the common outbound pipe 2A. Further, in response to this, the control signal SS2 is output from the outdoor unit control unit CU to the thermal valve controller CV, and the control signal S1 output from the thermal valve controller CV in response to the control signal SS2 causes the thermal valve V1. The opening and closing operation can be controlled. Further, the control signal Sm output in response to the operation in the main remote controller RM is input to the thermal valve controller CV, and the control signal S1 output from the thermal valve controller CV in response to the control signal Sm is used. The opening / closing operation of the thermal valve V1 can be controlled.

On the other hand, the return pipe 3B1 from the cold / hot water panel 51 is provided with a return temperature sensor 54. The return temperature sensor 54 detects the temperature (return temperature) of cold water in the corresponding return pipe 3B1 and outputs a detection signal indicating the detection result to the thermal valve controller CV.

The thermal valve controller CV controls the opening and closing of the thermal valve V1 based on the return temperature detected by the return temperature sensor 54 while responding to the operation of the main remote controller device RM (details will be described later). As a result, the user can control the operating state of the cold / hot water panel 51 by appropriately operating the remote controller RM.

The terminal remote control device RC has a heating switch 24 as a heating instruction means for causing the fan coil unit 52 to perform a heating operation for heating the room, and for causing the fan coil unit 52 to perform a cooling operation for cooling the room. A cooling switch 25 as a cooling instruction means, a stop switch 26 for stopping the operation of the fan coil unit 52, an indoor temperature setting switch 27 for setting the indoor temperature, and a display unit 28 for displaying the indoor set temperature and the operating state. It is possible to communicate with the terminal control unit 29.

<Main remote control device>
Next, the details of the main remote controller device RM shown in FIG. 1 will be described.

FIG. 2 shows the appearance of the main remote controller RM. The main remote controller RM includes a display unit 250, a "run / stop" button 253 for instructing operation start / stop of the outdoor unit 1 and the air conditioning terminal (cold / hot water panel 51), and the air conditioning terminal. The "timer" button 254 for instructing the operation by the timer, the "operation switching" button 255 for instructing the switching of the operation mode (cooling / heating, normal mode / save mode, etc.) of the air conditioning terminal, and the screen display 1 It is provided with a "back" button 257 for returning to the previous screen, a "menu / enter" button 258, and a cross key 259 in the up / down / left / right directions. The "run / stop" button 253, the "timer" button 254, the "operation switching" button 255, the "back" button 257, and the "menu / decision" button 258 are simply referred to as appropriate below. It is referred to as "operation button 253, etc.", and further, these operation buttons 253, etc. and the cross key 259 are collectively referred to as "operation unit 259, etc.". Although not shown, the main remote controller RM has a built-in CPU, a memory as a storage means, and the like.

The display unit 250 can switch and display various screens under the control of the CPU. In the illustrated example, the display unit 250 has a setting screen 200 for making settings related to the entire heat pump device 100 shown in FIG. 1, including temperature setting of circulating liquid (hot water / cold water), cooling / heating switching, and the like. Is displayed. The setting screen 200 is arranged in the center and has an operating state display area 200A indicating the operating state of the entire heat pump device 100, and is arranged at the right end and has a set temperature of the circulating fluid supplied from the outdoor unit 1 to the entire heat pump device 100. It is provided with a temperature setting display area 200B for displaying (corresponding to a numerical value of the temperature level. The user can set the temperature level using the operation unit 259 or the like).

In the illustrated example, the operating state display area 200A is displayed as "during cold water cooling operation" indicating a state in which the circulating liquid cooled by the outdoor unit 1 is supplied and the heat pump device 100 as a whole is being cooled. Has been done. Further, in the temperature setting display area 200B, a set temperature "15 ° C." of hot water set in advance (variably) by the user for cooling is displayed.

<Outdoor unit configuration>
Next, FIG. 3 shows a schematic system configuration of the outdoor unit 1. In FIG. 3, the outdoor unit 1 has a refrigerant circulation circuit 21 that circulates a synthetic compound gas such as HFC as a refrigerant to absorb and dissipate heat outside the room, and an air conditioning terminal (FIG. 1) in which, for example, an antifreeze liquid is circulated as a circulating liquid. In the example, heat exchange between the cold / hot water circulation circuit 22 (consisting of the cold / hot water outflow pipe 2 and the cold / hot water return pipe 3) that absorbs and dissipates heat in the cold / hot water panel 51 and the fan coil unit 52). It is a heat pump type heat source machine.

That is, the refrigerant circulation circuit 21 exchanges heat between the refrigerant and the outside air, the four-way valve 6 provided in the outdoor unit 1 for switching the circulation direction of the refrigerant, the compressor 7 for compressing the refrigerant, and the outside air. The outdoor heat exchanger 8 (corresponding to the heat source side heat exchanger), the expansion valve 9 (corresponding to the decompression means) for decompressing and expanding the refrigerant, the cold / hot water outflow pipe 2 and the cold / hot water return pipe 3 circulate. A water-refrigerant heat exchanger 11 (corresponding to a load-side heat exchanger) that exchanges heat between the circulating liquid and the refrigerant is connected by a refrigerant pipe 15. Further, an outdoor fan 10 for blowing air to the outdoor heat exchanger 8 is further provided.

The four-way valve 6 is a valve provided with four ports, and for each of the two ports for the refrigerant main path 15a (which constitutes a part of the refrigerant pipe 15), (a part of the refrigerant pipe 15 is provided. (Constituent) Switch which of the two ports for the other refrigerant subpath 15b is connected. The two ports for the refrigerant sub-path 15b are connected to each other by a refrigerant sub-path 15b arranged in a loop, and the compressor 7 is provided on the refrigerant sub-path 15b.

The compressor 7 pressurizes the refrigerant in the low-pressure gas state to bring it into the high-pressure gas state, and also functions as a pump that circulates the refrigerant in the entire refrigerant pipe 15 in the outdoor unit 1. A discharge temperature sensor 55 is provided in the refrigerant sub-path 15b on the discharge side of the compressor 7, detects the temperature of the refrigerant discharged from the compressor 7 (refrigerant discharge temperature), and represents the detection result. The signal is output to the outdoor unit control unit CU described later. Further, a refrigerant temperature sensor 57 is provided in the refrigerant main path 15a between the expansion valve 9 and the water-refrigerant heat exchanger 11, and flows between the expansion valve 9 and the water-refrigerant heat exchanger 11. The temperature of the refrigerant is detected, and a detection signal indicating the detection result is output to the outdoor unit control unit CU described later.

Further, the two ports for the refrigerant main path 15a of the four-way valve 6 are connected to each other by the refrigerant main path 15a arranged in a loop, and the outdoor heat exchanger 8 and the outdoor heat exchanger 8 are connected on the refrigerant main path 15a. The expansion valve 9 and the water-refrigerant heat exchanger 11 are provided.

The outdoor heat exchanger 8 functions as an evaporator that absorbs the heat of the outside air into the refrigerant and evaporates it into a gas state when the temperature of the refrigerant in a liquid state passing through the inside thereof is lower than the temperature of the outside air outside the room. Further, when the temperature of the refrigerant in a gas state passing through the inside is higher than the temperature of the outside air outside the room, it functions as a condenser that dissipates the heat of the refrigerant and condenses it in a liquid state. In the present embodiment, the outdoor heat exchanger 8 functions as a condenser.

The outdoor fan 10 blows air to the outdoor heat exchanger 8 to improve the performance of the outdoor heat exchanger 8.

The expansion valve 9 functions to expand the refrigerant in a high-pressure liquid state under reduced pressure to bring it into a low-pressure liquid state.

As described above, the water-refrigerant heat exchanger 11 is connected to the refrigerant main path 15a to allow the refrigerant to pass through the inside thereof, and is also connected to the cold / hot water outflow pipe 2 and the cold / hot water return pipe 3 to be inside the water-refrigerant heat exchanger 11. Pass the circulating fluid through. When the temperature of the gas-state refrigerant passing through the inside of the water-refrigerant heat exchanger 11 is higher than the temperature of the circulating liquid, it functions as a condenser that dissipates the heat to the circulating liquid and condenses it into the liquid state. .. Further, when the temperature of the liquid refrigerant passing through the inside of the water-refrigerant heat exchanger 11 is lower than the temperature of the circulating liquid, it functions as an evaporator that absorbs the heat of the circulating liquid with respect to the refrigerant and evaporates it into a gas state. do. In the present embodiment, the water-refrigerant heat exchanger 11 functions as an evaporator.

On the other hand, the cold / hot water circulation circuit 22 includes the water-hydrogen heat exchanger 11 provided in the outdoor unit 1, a circulation pump 12 for applying a circulating pressure to the circulating liquid, a systurn tank 13, and the air conditioning terminal (cold / hot). The water panel 51 and the fan coil unit 52) are connected by the cold / hot water outflow pipe 2 (specifically, the common outbound pipe 2A) and the cold / hot water return pipe 3 (specifically, the common return pipe 3A). It is formed.

The water-refrigerant heat exchanger 11 is connected to the hot / cold water outflow pipe 2 and the hot / cold water return pipe 3, and the systurn tank 13 and the circulation pump 12 are provided on the hot / cold water return pipe 3. ing.

The systan tank 13 separates air bubbles generated in the circulating fluid due to cavitation or the like (air-water separation function), absorbs the expanded circulating fluid in the hot / cold water circulation circuit 22, and replenishes the circulating fluid.

The circulation pump 12 functions to circulate the circulating liquid throughout the cold / hot water outflow pipe 2 and the cold / hot water return pipe 3.

The cold / hot water outflow pipe 2 (specifically, the common outbound pipe 2A) on the outlet side (outflow side) of the water-refrigerant heat exchanger 11 is provided with an outflow temperature sensor 56A as an outflow temperature determining means. The temperature (forwarding temperature) of the circulating fluid in the common outgoing pipe 2A is determined (detected in this example; the same applies hereinafter), and a detection signal indicating the detection result is output to the outdoor unit control unit CU described later. Further, the cold / hot water return pipe 3 (specifically, the common return pipe 3A) on the inlet side (inflow side) of the water-refrigerant heat exchanger 11 is provided with a return temperature sensor 56B as a return temperature determining means. The temperature (return temperature) of the circulating fluid in the common return pipe 3A is determined (detected in this example; the same applies hereinafter), and a detection signal representing the detection result is output to the outdoor unit control unit CU described later.

The outdoor unit 1 is provided with an outdoor unit control unit CU that controls the outdoor unit 1. The outdoor unit control unit CU is mainly composed of a microcomputer equipped with a CPU, a ROM, a RAM, and the like. The outdoor unit control unit CU and the main remote controller RM are connected by a bidirectional communication line, and signals can be exchanged with each other (see FIG. 1). As a result, as shown in FIG. 1, the outdoor unit control unit CU controls the entire outdoor unit 1 based on the control signal SS1 from the main remote controller device RM (details will be described later), and the corresponding control. The signal SS2 is output to the thermal valve controller CV.

In the configuration example shown in FIG. 1, in particular, between the outdoor unit control unit CU and the terminal control unit 29 of the fan coil unit 52, for example, a signal from the terminal control unit 29 is transmitted in one direction. It is connected by a terminal control line (so-called E-con communication line). For example, when the heating switch 24 (or the cooling switch 25) of the remote control device RC for a terminal is operated by a user and an instruction to start operation is given, the terminal control unit 29 receives the instruction signal. Then, in response to the received instruction signal, the terminal control unit 29 outputs a hot water request signal (or a cold water request signal related to the cooling operation) SC related to the heating operation to the outdoor unit control unit CU (FIG. 3). See the imaginary line inside). When the heating or cooling is stopped after the operation is started, the terminal control unit 29 is moved to the outside by performing an appropriate stop instruction operation (for example, pressing the stop switch 26) by the user. A stop request signal (not shown) for heating operation (or cooling operation) is output to the machine control unit CU.

Further, when the fan coil unit 52 is provided as described above in the configuration example shown in FIG. 1, the configuration is not limited to the configuration in which the fan coil unit 52 is operated by the terminal remote controller device RC. That is, the fan coil unit 52 itself may be provided with a switch or a display unit having the same function as the switch of the terminal remote control device RC, and the terminal remote control device RC may be omitted. In this case, when an instruction to start operation is given by the user operating a switch or the like of the fan coil unit 52, the terminal control unit 29 receives the instruction signal, and the hot water is sent to the outdoor unit control unit CU. The request signal (or the cold water request signal) SC is output. Similarly, when the user performs a stop instruction operation using the switch or the like of the fan coil unit 52, the terminal control unit 29 sends the outdoor unit control unit CU the stop request signal for heating operation (or cooling operation). Is output.

In the refrigerant circulation circuit 21 having the above configuration, the compressor 7 circulates the refrigerant in one direction on the refrigerant subpath 15b, and FIG. 3 shows the circulation direction during the cooling operation in the configuration example shown in FIG. As shown, the refrigerant discharged from the compressor 7 flows in the order of the outdoor heat exchanger 8, the expansion valve 9, and the water-refrigerant heat exchanger 11. As a result, the gas-state refrigerant sucked at low temperature and low pressure is compressed by the compressor 7 to become high temperature and high pressure gas, and then the outdoor fan 10 is used in the outdoor heat exchanger 8 (functioning as a condenser). By being cooled by the air blown, it changes to a high-pressure liquid while releasing heat to the outside air. The refrigerant that has become liquid in this way is depressurized by the expansion valve 9 to become a low-pressure liquid that easily evaporates. After that, the low-pressure liquid evaporates in the water-refrigerant heat exchanger 11 (functioning as an evaporator) and changes into a gas, so that heat is absorbed from the circulating liquid (cold water) from the cold / hot water return pipe 3. Then, the refrigerant returns to the compressor 7 again as a low-temperature, low-pressure gas.

At this time, the circulating liquid (cold water) cooled by the water-refrigerant heat exchanger 11 as described above is supplied from the cold / hot water outflow pipe 2 to the air conditioning terminal (cold / hot water panel 51, fan coil unit 52). It absorbs heat from the room air to cool the room, and then passes through the systurn tank 13 and returns to the circulation pump 12 again. By exchanging heat between the refrigerating cycle of the refrigerant circulation circuit 21 and the cold / hot water circulation circuit 22 as described above, a cooling operation for lowering the temperature of the indoor air is performed.

<Outdoor unit control unit>
Next, the main functional configuration of the outdoor unit control unit CU will be described with reference to FIG.

As shown in FIG. 4, the outdoor unit control unit CU functionally includes a compressor control unit 61 and an expansion valve control unit 62. The outdoor unit control unit CU corresponds to a control device.

The compressor control unit 61 includes an forward temperature control unit 61A and a return temperature control unit 61B.

The forward temperature control unit 61A performs so-called forward temperature control that controls the rotation speed of the compressor 7 according to the forward temperature of the circulating fluid detected by the forward temperature sensor 56A. In particular, in this example, the forward temperature control unit 61A sets the forward temperature detected by the forward temperature sensor 56A corresponding to, for example, an operation of the operation unit 259 in the main remote controller RM (details omitted). The rotation speed of the compressor 7 is controlled so as to reach a desired target temperature (target temperature). In this forward temperature control, since the supply temperature to the air conditioning terminal becomes constant, it is easy to maintain the output of the air conditioning terminal.

The forward temperature control unit 61A determines the magnitude of the load from the temperature difference between the forward temperature and the target forward temperature detected by the forward temperature sensor 56A, and the compressor 7 determines the magnitude of the load according to the magnitude of the load. The output of the outdoor unit 1 (heat pump type heat source machine) is smaller than the load when the forward temperature detected by the forward temperature sensor 56A does not reach the target forward temperature. This means that the output is insufficient. In this case, the rotation speed of the compressor 7 is increased to increase the output of the outdoor unit 1 (heat pump type heat source machine). On the other hand, when the forward temperature detected by the forward temperature sensor 56A reaches the target forward temperature, the outdoor unit 1 (in order to maintain the forward temperature detected by the forward temperature sensor 56A at the target forward temperature, the outdoor unit 1 ( The number of revolutions of the compressor 7 is reduced so that the output of the heat pump type heat source machine) and the load are balanced. Further, the forward temperature control unit 61A controls the rotation speed of the compressor 7 to be increased or decreased according to the fluctuation of the load. When the load decreases, the rotation speed of the compressor 7 decreases, and when the load increases, the compressor 7 decreases. Increase the number of revolutions of 7.

The return temperature control unit 61B performs so-called return temperature control, which controls the rotation speed of the compressor 7 according to the return temperature of the circulating fluid detected by the return temperature sensor 56B. In particular, in this example, the return temperature control unit 61B sets the return temperature detected by the return temperature sensor 56B, for example, in response to an operation of the operation unit 259 or the like in the main remote controller RM (details will be described later). The rotation speed of the compressor 7 is controlled so as to reach a desired target temperature (target return temperature). In this return temperature control, the forward temperature changes according to the load, and in the case of a low load, the forward temperature can be raised during the cooling operation, so that the efficiency of the heat pump device 100 can be improved. ..

The return temperature control unit 61B determines the magnitude of the load from the temperature difference between the return temperature and the target return temperature detected by the return temperature sensor 56B, and the compressor 7 determines the magnitude of the load according to the magnitude of the load. The output of the outdoor unit 1 (heat pump type heat source machine) is smaller than the load when the return temperature detected by the return temperature sensor 56B does not reach the target return temperature. This means that the output is insufficient. In this case, the output of the outdoor unit 1 (heat pump type heat source machine) is increased by increasing the rotation speed of the compressor 7. On the other hand, when the return temperature detected by the return temperature sensor 56B reaches the target return temperature, the outdoor unit 1 (in order to maintain the return temperature detected by the return temperature sensor 56B at the target return temperature, The number of revolutions of the compressor 7 is reduced so that the output of the heat pump type heat source machine) and the load are balanced. Further, the return temperature control unit 61B controls the rotation speed of the compressor 7 to increase or decrease according to the fluctuation of the load. When the load decreases, the rotation speed of the compressor 7 decreases, and when the load increases, the compressor 7 decreases. Increase the number of revolutions of 7.

The expansion valve control unit 62 controls the valve opening degree of the expansion valve 9 according to the refrigerant discharge temperature detected by the discharge temperature sensor 55. In particular, in this example, in the expansion valve control unit 62, the refrigerant discharge temperature detected by the discharge temperature sensor 55 is appropriately set (details are omitted) in response to, for example, the operation of the main remote controller device RM. The valve opening degree of the expansion valve 9 is controlled so as to reach the target discharge temperature.

Here, there are generally various types of air conditioning terminals, such as the above-mentioned cold / hot water panel 51 and fan coil unit 52. At this time, depending on the type of the air-conditioning terminal, it may be better to properly use the above-mentioned forward temperature control and return temperature control during operation (cooling operation) due to its characteristics. This will be described with reference to FIG.

In FIG. 5, for example, when the fan coil unit 52 shown in FIG. 1, which is a kind of forced convection type terminal, is used for cooling operation, the blower fan circulates the indoor air, so that the operation is started at the initial stage. After dehumidifying the humidity in the room to some extent (that is, latent heat treatment) under high load, stable operation is achieved. Therefore, even if the return temperature control is performed with the main purpose of improving efficiency, it is unlikely that comfort will be impaired by high humidity. Therefore, when the forced convection terminal is operated, it is preferable that the return temperature control with an emphasis on efficiency is always executed regardless of the magnitude of the load, that is, regardless of the rotation speed of the compressor 7.

On the other hand, for example, when the cooling operation is performed by the cold / hot water panel 51 shown in FIG. 1, which is a kind of radiant terminal, the compressor 7 has a high rotation speed range at the time of high load at the initial stage of operation. It is driven by and has a large output, and can dehumidify the moisture around the cold / hot water panel 51 to some extent (that is, latent heat treatment). Even if it is not exhausted, the number of revolutions of the compressor 7 is reduced. In this case, if the return temperature control is performed, the temperature of the circulating fluid supplied to the panel will gradually increase at the timing when the panel itself has cooled to some extent (even if the temperature in the room has not yet decreased). As a result, the temperature inside the room is less likely to drop, and as a result, the humidity inside the room does not drop completely, leading to an unpleasant situation. Therefore, when the cold / hot water panel 51 performs the cooling operation, there is a scene in which it is better to control the forward temperature in order to reduce the humidity in the room.

Therefore, when the cooling operation is performed by the cold / hot water panel 51, as shown in FIG. 5, when the current rotation speed of the compressor 7 corresponds to the zone A in the preset high rotation speed range, the compressor is controlled. The unit 61 causes the return temperature control unit 61B to execute the return temperature control, and when the current rotation speed of the compressor 7 corresponds to the zone B in the preset medium rotation speed range, the compressor control unit 61 goes out. When the temperature control unit 61A is made to execute the forward temperature control and the current rotation speed of the compressor 7 corresponds to the zone C in the preset low rotation speed region, the compressor control unit 61 returns the compressor control unit 61B. To execute the return temperature control.

During the cooling operation by the cold / hot water panel 51, when the compressor 7 is driven in the high rotation speed range (zone A) under a high load, the output is large and the circulating liquid supplied to the cold / hot water panel 51 has a large output. The forward temperature tends to decrease, and the moisture around the cold / hot water panel 51 can be dehumidified to some extent (that is, latent heat treatment), and as the load decreases, the compressor 7 rotates in the high rotation speed range (zone A). When the number decreases (when the output decreases), the return temperature control is executed in order to improve the efficiency as much as possible. Then, when the compressor 7 is driven in the medium rotation speed range (zone B) at the time of medium load, where the cold / hot water panel 51 itself is cooled to some extent and the temperature around the cold / hot water panel 51 is stable, Since it is necessary to further reduce the indoor humidity in order to improve comfort, the forward temperature of the circulating fluid supplied to the cold / hot water panel 51 is maintained at a low temperature so that the indoor temperature is lowered. Let control be executed. Further, when the temperature of the entire room is lowered and the compressor 7 is driven in the low rotation speed range (zone C) at a low load, the temperature and humidity environment in the room is in a good state. , The return temperature control is executed with an emphasis on efficiency.

As shown in FIG. 5, a hysteresis is provided at the boundary between the rotation speed zones, and the rotation speed zones are switched in the direction in which the rotation speed of the compressor 7 becomes smaller. The boundary and the boundary between the rotation speed zones when the rotation speed zones are switched in the direction in which the rotation speed of the compressor 7 increases are different. That is, the boundary when switching from the high rotation speed region (zone A) where the rotation speed of the compressor 7 is high to the medium rotation speed region (zone B) adjacent to the side where the rotation speed is low is 65 rps (in other words,). When the rotation speed of the compressor 7 gradually decreases from a high state to 65 rps, the zone A is switched to the zone B). Similarly, the boundary when the rotation speed of the compressor 7 is switched from the middle rotation speed region (zone B) to the low rotation speed region (zone C) is 35 rps.

On the contrary, the boundary when switching from the low rotation speed region (zone C) where the rotation speed of the compressor 7 is small to the middle rotation speed region (zone B) adjacent to the side where the rotation speed is high is 40 rps (in other words). , When the rotation speed of the compressor 7 gradually increases from a low state to 40 rps, the zone C is switched to the zone B). Similarly, the boundary when the rotation speed of the compressor 7 is switched from the middle rotation speed region (zone B) to the high rotation speed region (zone A) is 70 rps.

In the present embodiment, in view of the above, the outdoor unit is connected to the outdoor unit 1 via the cold / hot water outflow pipe 2 and the cold / hot water return pipe 3, depending on what kind of air conditioner terminal is connected to the outdoor unit 1. The compressor control unit 61 of the machine control unit CU switches between performing the forward temperature control by the forward temperature control unit 61A and performing the return temperature control by the return temperature control unit 61B. Hereinafter, the details of the method will be described step by step using the flowchart of FIG.

<Control of compressor control unit>
First, the control procedure by the compressor control unit 61 during the cooling operation is shown in the flowchart of FIG. 6A. In FIG. 6A, first, in step S1, the compressor control unit 61 determines whether or not the outdoor unit 1 is in the operation start state. Specifically, the operation start state is, for example, a case where the outdoor unit 1 is started from the stopped state by an appropriate operation start operation of the outdoor unit 1 by the user via the main remote controller device RM or the terminal remote controller device RC. Or, it is a case where the operation of the outdoor unit 1 is restarted by restarting after the operation is stopped. The determination in step S1 is not satisfied (S1: NO) until the operation start state is reached, and the loop waits. When the operation start state is reached, the determination in step S1 is satisfied (S1: YES), and the process proceeds to step S2.

In step S2, the compressor control unit 61 determines whether or not the outdoor unit 1 is in the operation end state. That is, when the cooling operation is performed under the control of the rotation speed as described later and the cooling load becomes small, the return temperature detected by the return temperature sensor 56B returns to the target without operating the outdoor unit 1. May reach above temperature. In this case, the outdoor unit 1 is stopped by the known control by the outdoor unit control unit CU and enters the standby state (that is, the operation of the outdoor unit 1 is temporarily terminated). In step S2, the compressor control unit 61 determines whether or not the outdoor unit 1 is in this standby state. If the operation is in the end state (that is, the standby state), the determination in step S2 is satisfied (S2: YES), and this flow is ended. On the other hand, while the operation is not completed (that is, the standby state), the determination in step S2 is not satisfied (S2: NO), and the process proceeds to step S3.

In step S3, the compressor control unit 61 determines whether or not there is an operation request for the cold / hot water panel 51. The outdoor unit control unit CU determines, for example, as the control signal SS1 output from the main remote control device RM, an identification signal indicating the operation request of the cold / hot water panel 51 is used to determine whether or not there is an operation request for the cold / hot water panel 51. When it is acquired (however, the illustration in FIG. 1 is omitted), it is determined that the operation request of the cold / hot water panel 51 has been made, or the main remote control device RM and the cold / hot water panel 51 are associated with each other in advance (initially). When the outdoor unit control unit CU acquires the control signal SS1 output from the main remote control device RM (such as registering the air conditioner terminal to be connected at the time of setting), the signal is assumed to be an operation request from the cold / hot water panel 51. It is determined that there is an operation request for the cold / hot water panel 51, or the outdoor unit control unit CU stores that the air conditioner terminal corresponding to the thermal valve V1 is the cold / hot water panel 51, and the thermal valve controller CV. When the outdoor unit control unit CU acquires the control signal S1 from the thermal valve V1, it is sufficient to use a known method such as determining that the operation request of the cold / hot water panel 51 has been made. If there is an operation request for the cold / hot water panel 51, the determination is satisfied (S3: YES), and the process proceeds to step S4. The case where the determination in step S3 is satisfied is at least the case where there is an operation request for the cold / hot water panel 51 in the configuration example of FIG. 1, and the operation request for both the cold / hot water panel 51 and the fan coil unit 52 is satisfied. In some cases, the determination in step S3 is satisfied.

In step S4, the compressor control unit 61 determines which rotation speed range of zones A to C shown in FIG. 5 the current rotation speed (indicated rotation speed or actual rotation speed) of the compressor 7 is. Here, it is determined whether or not the current rotation speed of the compressor 7 is in the middle rotation speed range (zone B). When the current rotation speed of the compressor 7 is in the middle rotation speed range (zone B), the determination is satisfied (S4: YES), and the process proceeds to step S5.

In step S5, the compressor control unit 61 uses the forward temperature control unit 61A to set the temperature of the circulating fluid (cold water) (the temperature appropriately set by the operation of the operation unit 259 or the like in the main remote controller RM described above). Based on the above, the corresponding target forward temperature is calculated and set by a known method (the target forward temperature can be uniquely determined with respect to the set temperature), and the process proceeds to step S6. The forward temperature control unit 61A of the compressor control unit 61 that executes this step S5 functions as a target forward temperature setting means for setting the target forward temperature, and the target forward temperature is set to, for example, the same temperature as the set temperature.

In step S6, in the compressor control unit 61, the forward temperature of the circulating fluid detected by the forward temperature control unit 61A at this time from the forward temperature sensor 56A is the target forward temperature set in step S5. Is determined whether or not the temperature is exceeded. If the forward temperature exceeds the target forward temperature, the determination is satisfied (S6: YES), and the process proceeds to step S7. In step S7, the compressor control unit 61 increases the rotation speed of the compressor 7 by the forward temperature control unit 61A. Then, the process returns to step S2 and the same procedure is repeated.

In the determination in step S6, if the forward temperature is equal to or lower than the target forward temperature, the determination is not satisfied (S6: NO), and the process proceeds to step S8. In step S8, the compressor control unit 61 reduces the rotation speed of the compressor 7 by the forward temperature control unit 61A. Then, the process returns to step S2 and the same procedure is repeated.

As described above, when the rotation speed of the compressor 7 is in the middle rotation speed range (zone B) while there is an operation request for the cold / hot water panel 51, step S3 → step S4 → step S5 → step. By repeating S6 → step S7 or step S8 → step S2 → step S3 ..., the compressor rotation speed increase / decrease control is executed according to the magnitude of the target forward temperature and the forward temperature, that is, the forward temperature is the said. The forward temperature control unit 61A executes the forward temperature control that controls the rotation speed of the compressor 7 so as to match the target forward temperature.

On the other hand, if there is no operation request for the cold / hot water panel 51 in step S3, the determination is not satisfied (S3: NO), and the process proceeds to step S9. Here, the case where the determination in step S3 is not satisfied is at least the case where there is no operation request for the cold / hot water panel 51 in the configuration example of FIG. 1, and there is no operation request for the cold / hot water panel 51, and the fan coil unit 52. When there is an operation request independently (for example, when the outdoor unit control unit CU acquires an identification signal indicating the operation request of the fan coil unit 52 as the control signal Sc output from the terminal control unit 29), the step S3 is performed. The determination is not satisfied (S3: NO), and the process proceeds to step S9. The compressor control unit 61 that executes step S3 of the air-conditioning terminal to be operated is operated based on the operation request (signal representing the air-conditioning terminal to be operated) of the air-conditioning terminal (cold / hot water panel 51, fan coil unit 52). It functions as a terminal determination means for determining the type.

In step S9, the compressor control unit 61 is set by the return temperature control unit 61B to set the temperature of the circulating fluid (cold water) (the temperature appropriately set by the operation of the operation unit 259 or the like in the main remote controller RM described above). Based on the above, the corresponding target return temperature is calculated and set by a known method (for example, based on a predetermined rule that uniquely determines the target return temperature from the set temperature), and in step S10. Move.

As the predetermined rule, an additional value Ts + α obtained by adding a predetermined numerical value α to the set temperature Ts set by the main remote controller RM, which is the numerical value of the temperature level supplied to the air conditioning terminal, is returned to the target. It can be set as the temperature Tm. At this time, specifically, in the range of Ts of 6 ° C. to 20 ° C., an appropriate value in the range of 5 ° C. to 15 ° C. is applied to α. Which value to apply to α may be optionally selectable in the main remote controller RM, or α is fixedly set to an appropriate value in the range of 5 ° C. to 15 ° C. in advance. May be good.

The predetermined rule is not limited to the method of setting the target return temperature Tm as the addition value obtained by adding a predetermined value from the value of the temperature value of cold water itself as described above. For example, when strong / medium / weak indicating the cooling strength is used as the temperature level that can be set in the cooling operation, the temperature conversion values corresponding to the strong / medium / weak (for example, strong is 7, medium is 13, The weakness may be a rule in which 20) is stored in advance and the added value obtained by adding a predetermined value from the value (temperature conversion value) Ts is set as the target return temperature Tm. Alternatively, as the temperature level that can be set in the cooling operation, even when a temperature level having 9 levels of cooling strength is used, for example, a numerical value of 1 to 9 is used to express the cooling strength, and 9 levels of cooling are used. The temperature conversion value corresponding to the strength of the above may be stored in advance, and the added value obtained by adding a predetermined value to the value (temperature conversion value) Ts may be set as the target return temperature Tm.

The return temperature control unit 61B of the compressor control unit 61 that executes this step S9 functions as a target return temperature setting means for setting the target return temperature. After setting the target return temperature as described above, the process proceeds to step S10. In step S10, the compressor control unit 61 is circulated by the return temperature control unit 61B and detected from the return temperature sensor 56B at this point. It is determined whether or not the return temperature of the liquid exceeds the target return temperature set in step S9. If the return temperature is higher than the target return temperature, the determination is satisfied (S10: YES), and the process proceeds to step S11. In step S11, the compressor control unit 61 increases the rotation speed of the compressor 7 by the return temperature control unit 61B. Then, the process returns to step S2 and the same procedure is repeated.

In the determination in step S10, if the return temperature is equal to or lower than the target return temperature, the determination is not satisfied (S10: NO), and the process proceeds to step S12. In step S12, the compressor control unit 61 reduces the rotation speed of the compressor 7 by the return temperature control unit 61B. Then, the process returns to step S2 and the same procedure is repeated.

As described above, while there is no operation request for the cold / hot water panel 51 and there is an operation request for the fan coil unit 52 other than the cold / hot water panel 51, step S3 → step S9 → step S10 → step S11 or step S12 → step. By repeating S2 → step S3 ..., the compressor rotation speed increase / decrease control is executed according to the magnitude of the target return temperature and the return temperature, that is, the compressor so that the return temperature matches the target return temperature. The return temperature control for controlling the number of rotations of 7 is executed by the return temperature control unit 61B.

If the rotation speed of the compressor 7 is not in the middle rotation speed range (zone B) in step S4, the determination is not satisfied (S4: NO), and the process proceeds to step S9. When the determination in step S4 is not satisfied, the rotation speed of the compressor 7 is a high rotation speed region (zone A) or a low rotation speed region other than the middle rotation speed region (zone B) shown in FIG. This is the case of (Zone C).

The procedure after step S9 is the same as described above, and the description thereof will be omitted, but the rotation speed of the compressor 7 is in the high rotation speed range (zone A) while the operation of the cold / hot water panel 51 is requested. Alternatively, in the case of a low rotation speed range (zone C), step S3 → step S4 → step S9 → step S10 → step S11 or step S12 → step S2 → step S3 ... Are repeated to obtain the target return temperature. The rotation speed increase / decrease control of the compressor 7 is executed according to the magnitude of the return temperature, that is, the return temperature control that controls the rotation speed of the compressor 7 so that the return temperature matches the target return temperature is the return temperature. It is executed by the control unit 61B.

The air conditioning in which the compressor control unit 61 that executes the step S3, step S4, step S5, step S6, step S7, step S8, step S9, step S10, step S11, and step S12 of FIG. 6 is operated. It functions as a switching control means for switching and executing required temperature control (the forward temperature control and the return temperature control) based on the type of the terminal.

<Control by expansion valve control unit>
Next, the control procedure by the expansion valve control unit 62 during the cooling operation is shown in the flowchart of FIG. 6B. In FIG. 6B, first, in step S101, the expansion valve control unit 62 determines whether or not the outdoor unit 1 is in the operation start state in the same manner as in step S1 of FIG. 6A. The determination in step S101 is not satisfied (S101: NO) until the operation start state is reached, and the loop waits. When the operation start state is reached, the determination in step S101 is satisfied (S101: YES), and the process proceeds to step S102.

In step S102, the expansion valve control unit 62 determines whether or not the outdoor unit 1 is in the operation end state in the same manner as in step S2 of FIG. 6A. When the operation end state (that is, the standby state) is reached, the determination in step S102 is satisfied (S102: YES), and this flow ends. On the other hand, while the operation end state (that is, the standby state) is not reached, the determination in step S102 is not satisfied (S102: NO), and the process proceeds to step S103.

In step S103, the expansion valve control unit 62 determines whether or not the refrigerant discharge temperature detected by the discharge temperature sensor 55 at this point is lower than the target discharge temperature. If the refrigerant discharge temperature is lower than the target discharge temperature, the determination is satisfied (S103: YES), and the process proceeds to step S104.

In step S104, the expansion valve control unit 62 reduces the valve opening degree of the expansion valve 9. After that, the process returns to step S102 and the same procedure is repeated.

On the other hand, in the determination in step S103, if the refrigerant discharge temperature is equal to or higher than the target discharge temperature, the determination is not satisfied (S103: NO), and the process proceeds to step S105.

In step S105, the expansion valve control unit 62 increases the valve opening degree of the expansion valve 9. After that, the process returns to step S102 and the same procedure is repeated.

As described above, the processing of steps S103, S104, and S105 performs refrigerant discharge temperature control that controls the valve opening degree of the expansion valve 9 so that the refrigerant discharge temperature matches the target discharge temperature. ..

<Example of cooling operation behavior>
Next, an example of the characteristic cooling operation behavior in the configuration example shown in FIG. 1 will be described with reference to FIG. In the figure, FIG. 7A shows the time course of the operating state of the cold / hot water panel 51 (in the figure, the operating state is referred to as “ON” and the stopped state is referred to as “OFF”). 7 (b) shows, with time, whether the control mode of the heat pump device 100 (abbreviated as “HP” in the figure; specifically, the compressor 7) is the forward temperature control or the return temperature control. FIG. 7 (c) shows the transition over time of the increase / decrease in the cooling load by the cold / hot water panel 51, and FIG. 7 (d) shows the transition of the circulating fluid in the cold / hot water outflow pipe 2. Cold water temperature (detected by the forward temperature sensor 56A), the return chilled water temperature of the circulating fluid in the cold / hot water return pipe 3 (detected by the return temperature sensor 56B), the target forward temperature at the time of the forward temperature control, and the return temperature control. The target return temperature at time (see step S5 and step S9 in FIG. 6) and the time course of each are shown, and FIG. 7 (e) shows the time course of the rotation speed of the compressor 7.

FIG. 7 illustrates a case where only the cold / hot water panel 51 is in operation (see time t1 to t6 in FIG. 7A). At time t1 to t2, the cooling load is high (see time t1 to t2 in FIG. 7 (c)), and the rotation speed of the compressor 7 is about 90 rps (see time t1 to t2 in FIG. 7 (e)). Since it is in the high rotation speed range (zone A), the return temperature is controlled as described above (see time t1 to t2 in FIG. 7B), and the actual return cold water temperature is the target return temperature of about 17 ° C. (FIG. 7). The rotation speed of the compressor 7 is controlled so as to be the time t1 to t2 in (d) (see the time t1 to t2 in FIG. 7E). At this time, the actual cold water temperature also becomes constant at about 7 ° C. (see time t1 to t2 in FIG. 7 (d)).

After that, when the room temperature of the room A in which the cold / hot water panel 51 is installed decreases with the passage of time and the cooling load decreases (see time t2 to t3 in FIG. 7C), the return temperature control causes the above. The rotation speed of the compressor 7 gradually decreases (see time t2 to t3 in FIG. 7 (e)), and as a result, the actual cold water temperature gradually increases (see time t2 to t3 in FIG. 7 (d)). ..

Then, the rotation speed of the compressor 7 decreases from the high rotation speed region (zone A) to the medium rotation speed region (zone B) due to the decrease in the compressor 7 rotation speed accompanying the decrease in the cooling load (compressor 7). When the rotation speed becomes 65 rps or less), the return temperature control is switched to the forward temperature control (see time t3 in FIG. 7B), and the actual cold water temperature is set as the target forward temperature by executing the forward temperature control. The rotation speed of the compressor 7 is controlled so as to be about 7 ° C. (see time t3 to t4 in FIG. 7 (e)). That is, at the time of switching to the forward temperature control, the actual cold water temperature exceeds the target forward temperature of about 7 ° C. Therefore, in order to lower the actual cold water temperature (see time t3 to t4 in FIG. 7 (d)), the rotation speed of the compressor 7 is temporarily increased (see time t3 to t4 in FIG. 7 (e)).

After that, the rotation speed of the compressor 7 is controlled so that the actual cold water temperature reaches the target temperature of about 7 ° C. (see time t4 to t5 in FIG. 7D). At this time, as described above, the actual cold water temperature becomes constant at about 7 ° C., while the actual return cold water temperature becomes more and more according to the cooling load, and the cooling load decreases (time t4 to t5 in FIG. 7 (c)). (See), the rotation speed of the compressor 7 gradually decreases (see times t4 to t5 in FIG. 7 (e)), and as a result, the actual return chilled water temperature also gradually decreases (time in FIG. 7 (d)). See t4 to t5).

Then, the rotation speed of the compressor 7 decreases from the medium rotation speed region (zone B) to the low rotation speed region (zone C) due to the decrease in the compressor 7 rotation speed accompanying the decrease in the cooling load (compressor 7). When the rotation speed becomes 35 rps or less), the forward temperature control is switched to the return temperature control (see time t5 in FIG. 7B), and the actual return chilled water temperature is set as the target forward temperature by executing the return temperature control. The rotation speed of the compressor 7 is controlled so that the temperature becomes about 17 ° C. (time t5 to t6 in FIG. 7 (e)). That is, at the time of switching to the return temperature control, the actual return chilled water temperature is below the target return temperature of about 17 ° C. Therefore, in order to raise the actual return chilled water temperature (see time t5 to t6 in FIG. 7 (d)), the rotation speed of the compressor 7 decreases (see time t5 to t6 in FIG. 7 (e)). As a result, the actual return chilled water temperature rises (see time t5 to t6 in FIG. 7 (d)), and the actual chilled water temperature that gradually increases according to the cooling load also rises (time in FIG. 7 (d)). See t5 to t6).

After that, the rotation speed of the compressor 7 is controlled so that the actual return chilled water temperature becomes the target return temperature of about 17 ° C. (see time t6 to FIG. 7D). At this time, as described above, the actual return chilled water temperature becomes constant at about 17 ° C., while the actual chilled water temperature becomes constant according to the cooling load, the cooling load decreases, and becomes constant at a low load (Fig.). 7 (c) time t6 ~) and the actual cold water temperature also decreases to match it and then becomes constant (see time t6 ~ in FIG. 7D).

Further, in FIG. 7, a case where only the cold / hot water panel 51 is operated has been described, but when the cold / hot water panel 51 is operated, an air conditioning terminal other than the cold / hot water panel 51, here, a fan coil unit 52 The control corresponding to the cold / hot water panel 51 is executed regardless of whether or not the cold / hot water panel 51 is operated, and the case where both the cold / hot water panel 51 and the fan coil unit 52 are operated is also shown in FIG. As shown, the forward temperature control or the return temperature control is switched and executed according to the rotation speed of the compressor 7. When only the fan coil unit 52 is operated, the return temperature control is executed regardless of the rotation speed of the compressor 7.

<Effect of embodiment>
As described above, according to the heat pump device 100 (heat pump type chilled water cooling device) of the present embodiment, the type of the air conditioning terminal to be operated is determined based on the operation request of the air conditioning terminal, and the operation is performed as a result of the determination. When it is determined that is a radiation type terminal (cold / hot water panel 51), the compressor control unit 61 is in a high rotation speed range (zone A) in which the current rotation speed of the compressor 7 is preset. If there is, the return temperature control unit 61B executes the return temperature control, and if the current rotation speed of the compressor 7 is in the preset medium rotation speed range (zone B), the forward temperature control unit 61A If the current rotation speed of the compressor 7 is in the preset low rotation speed range (zone C), the return temperature control unit 61B executes the return temperature control. On the other hand, when it is determined that the operation is other than the radiation type terminal (fan coil unit 52), the compressor control unit 61 is requested to execute the return temperature control by the return temperature control unit 61B. I made it. Thereby, during the cooling operation, the optimum control of the forward temperature control and the return temperature control can be executed for each type of the air conditioning terminal.

In particular, when a radiation type terminal (cold / hot water panel 51) is operated as the air-conditioning terminal, the compressor control unit 61 has a high rotation speed range (zone A) in which the current rotation speed of the compressor 7 is preset. ), By executing the return temperature control by the return temperature control unit 61B, when the current compressor 7 is driven in the high rotation speed range (zone A), the output is large and the cold / hot water panel The flow temperature of the circulating fluid supplied to 51 tends to decrease, and the moisture around the cold / hot water panel 51 in Room A can be dehumidified to some extent (that is, latent heat treatment), and as the load decreases, the high rotation speed range (zone). Efficiency can be improved when the number of revolutions of the compressor 7 decreases in A). Then, if the current rotation speed of the compressor 7 is in the preset medium rotation speed range (zone B), the forward temperature control unit 61A executes the forward temperature control to control the cold / hot water panel 51 itself. Is cold to some extent and the temperature around the cold / hot water panel 51 becomes stable. When the compressor 7 is driven in the medium rotation speed range (zone B) at the time of medium load, the supply temperature to the cold / hot water panel 51 becomes high. Since the target temperature is reached and maintained constant at a low temperature, the temperature in room A is surely lowered, and the humidity in room A is lowered and comfortable without becoming stable in a high humidity state. The sex can be improved. Further, if the current rotation speed of the compressor 7 is in a preset low rotation speed range (zone C), the return temperature control unit 61B executes the return temperature control to compress the compressor 7 at a low load. When the machine 7 is driven in the low rotation speed range (zone C), the temperature and humidity environment in room A is already in place, so it is possible to improve efficiency by controlling the return temperature with an emphasis on efficiency. can. Further, when a forced convection terminal (fan coil unit 52) other than the radiation terminal (cold / hot water panel 51) is operated as the air conditioning terminal, the air in the room A is circulated by the blower fan, so that the air in the room A is circulated at the initial stage of operation. After dehumidifying the humidity in the room to some extent evenly (that is, latent heat treatment) under high load, stable operation is performed, so it is unlikely that comfort will be impaired by high humidity. Efficiency can be improved.

The present invention is not limited to the above embodiment, and various modifications can be made without changing the gist of the invention.

For example, in the above embodiment, the outdoor unit control unit CU shown in FIG. 4 functionally includes the compressor control unit 61 and the expansion valve control unit 62, but as shown in FIG. 8, the outdoor unit control The unit CU may functionally include the compressor control unit 61α and the expansion valve control unit 62α.

The compressor control unit 61α is a room temperature sensor that detects the set temperature set by the operation of the operation unit 259 or the like in the main remote control device RM and the temperature in the room where the remote control device RM is installed built in the main remote control device RM. The magnitude of the load is determined from the temperature difference from (not shown), and the rotation speed of the compressor 7 is controlled to increase or decrease according to the magnitude of the load. The expansion valve control unit 62α includes an forward temperature control unit 62A and a return temperature control unit 62B.

The expansion valve control unit 62α includes an forward temperature control unit 62A and a return temperature control unit 62B. The forward temperature control unit 62A controls the forward temperature by controlling the opening degree of the expansion valve 9 according to the forward temperature of the circulating fluid detected by the forward temperature sensor 56A. In particular, in this example, the forward temperature control unit 62A sets the forward temperature detected by the forward temperature sensor 56A corresponding to, for example, an operation of the operation unit 259 in the main remote controller RM (details omitted). The opening degree of the expansion valve 9 is controlled so as to reach a desired target temperature (target going temperature). The return temperature control unit 62B performs return temperature control that controls the opening degree of the expansion valve 9 according to the return temperature of the circulating fluid detected by the return temperature sensor 56B. In particular, in this example, the return temperature control unit 62B sets the return temperature detected by the return temperature sensor 56B corresponding to, for example, an operation of the operation unit 259 or the like in the main remote controller device RM (details will be described later). The opening degree of the expansion valve 9 is controlled so as to reach a desired target temperature (target return temperature).

Then, when the cooling operation is performed by the cold / hot water panel 51, when the compressor control unit 61α determines that the current rotation speed of the compressor 7 corresponds to the zone A in the preset high rotation speed range, the compressor expands. The valve control unit 62α causes the return temperature control unit 62B to execute the return temperature control, and the compressor control unit 61α determines that the current rotation speed of the compressor 7 corresponds to the zone B in the preset medium rotation speed range. When this happens, the expansion valve control unit 62α causes the forward temperature control unit 62A to perform the forward temperature control, and the compressor control unit 61α sets the current rotation speed of the compressor 7 in a preset low rotation speed zone. When it is determined that C is applicable, the expansion valve control unit 62α causes the return temperature control unit 62B to execute the return temperature control.

Further, when the fan coil unit 52 performs the cooling operation, the return temperature control is always executed regardless of the magnitude of the load, that is, regardless of the rotation speed of the compressor 7.

In the heat pump device 100 having the outdoor unit 1 provided with the outdoor control unit CU shown in FIG. 8, by controlling as described above, the outdoor unit 1 provided with the outdoor control unit CU shown in FIG. 4 described above. It is possible to exert the same effect as the heat pump device 100 having the above.

Further, for example, in the above embodiment, the forward temperature of the circulating fluid in the common forward pipe 2A is detected by the forward temperature sensor 56A, and the detected value is used for control, but the forward temperature sensor 56A is omitted (or). The compressor as the detection value of the discharge temperature sensor 55, the detection value of the return temperature sensor 56B, the detection value of the refrigerant temperature sensor 57, and the refrigerant state amount related to the refrigerant circulation amount). The forward temperature may be estimated and determined (estimated) from the rotation speed of 7 and the valve opening degree of the expansion valve 9 as the refrigerant state amount related to the refrigerant circulation amount.

Also in the above modified example, the outdoor unit control unit CU functionally includes a compressor control unit 61 and an expansion valve control unit 62. The compressor control unit 61 includes an forward temperature control unit 61A'(not shown) instead of the forward temperature control unit 61A in FIG. 4, and a return temperature control unit 61B similar to that in FIG.

In the forward temperature control unit 61A', the refrigerant discharge temperature detected by the discharge temperature sensor 55, the return temperature of the circulating fluid detected by the return temperature sensor 56B, and the refrigerant temperature detected by the refrigerant temperature sensor 57 And, circulation in the common forward pipe 2A based on the rotation speed of the compressor 7 as the refrigerant state amount related to the refrigerant circulation amount and the valve opening degree of the expansion valve 9 as the refrigerant state amount related to the refrigerant circulation amount. The forward temperature of the liquid is determined (estimated), and the forward temperature control is performed to control the rotation speed of the compressor 7 according to the determined forward temperature. In particular, in this example, the forward temperature control unit 61A'is a desired target in which the determined forward temperature is set (details omitted) in response to, for example, an operation of the operation unit 259 in the main remote controller RM. The rotation speed of the compressor 7 is controlled so as to reach the temperature (target temperature).

As described above, the forward temperature control unit 61A'determines (estimates) the forward temperature and controls the forward temperature according to the determined forward temperature. The temperature is not limited to the modification, but the temperature is estimated by another method, and the temperature control unit 61A'controls the temperature according to the estimated (determined) temperature. You may.

Further, also in the above-described modified example, the same effect as that of the above-described embodiment can be obtained. That is, the type of the air-conditioning terminal to be operated is determined, and based on the result of the determination, the forward temperature control unit 61A'is used to control the forward temperature (based on the forward temperature determined from the return temperature) or the return temperature control. Return temperature control (based on the return temperature) by unit 61B is performed. Thereby, during the cooling operation, the optimum control of the forward temperature control and the return temperature control can be executed for each type of the air conditioning terminal.

Further, in the above embodiment, when the radiation type terminal (cold / hot water panel 51) is operated, the optimum control of the forward temperature control and the return temperature control is executed according to the rotation speed of the compressor 7. However, since the rotation speed of the compressor 7 fluctuates immediately after the start of operation, the compressor control unit 61 shall execute only the return temperature control by the return temperature control unit 61B for a predetermined time from the start of operation. It is preferable to execute the above control according to the rotation speed of the compressor 7 after a predetermined time when the rotation speed of the compressor 7 stabilizes.

The number of air conditioning terminals provided in the heat pump device 100 is not limited to two as described above, and may be three or more.

Further, in the above embodiment, as the heat pump type heat source machine, the outdoor fan 10 which blows the outside air while passing the refrigerant through the outdoor heat exchanger 8 which is the heat source side heat exchanger is provided, and the outside air as the heat source and the refrigerant are used. The case where the outdoor unit 1 of the air heat source type is used is described as an example, but the present invention is not limited to this. That is, the heat pump type heat source machine may be configured such that water or antifreeze liquid is supplied to the heat source side heat exchanger and the liquid and the refrigerant exchange heat in the heat source side heat exchanger.
Further, a heat source side heat exchanger may be provided in the ground or in a relatively large-capacity water source, and the heat source side heat exchanger may be configured to exchange heat between the ground or the water source and the refrigerant. Further, a composite heat source type configuration may be provided in which a heat pump circuit using the heat of the underground or the water source and another heat pump circuit using air heat are provided.
Further, if the heat source side heat exchanger can exchange heat with the refrigerant, it includes other substances (for example, smoke generation, smoke exhaust, various high temperature gases, etc.) in place of the liquid, the outside air, and the water source. Gas, hot sand, dust, fluid solid containing various particles, etc.) can be passed through the heat source side heat exchanger, or heat from sunlight, reflected light, or other radiation can be supplied to the heat source side heat exchanger for use. good.

1 Outdoor unit 2 Cold / hot water outflow pipe 3 Cold / hot water return pipe 7 Compressor 8 Outdoor heat exchanger 9 Expansion valve 11 Water-refrigerator heat exchanger 12 Circulation pump 22 Cold / hot water circulation circuit 51 Cold / hot water panel 52 Fan coil unit 56A Outgoing temperature sensor 56B Return temperature sensor 61 Compressor control unit 100 Heat pump device (heat pump type cold water cooling device)
CU outdoor unit control unit

Claims (1)

A heat pump type heat source machine having a compressor for compressing the refrigerant, a load-side heat exchanger for heat exchange between the circulating liquid and the refrigerant, a decompression means, and a heat source-side heat exchanger.
The load side heat exchanger of the heat pump type heat source machine, an air conditioning terminal that air-conditions the air-conditioned space using the circulating liquid as a heat source, and a circulation pump that circulates the circulating liquid are connected in a ring shape by a pipe. The circulation circuit in which the circulating fluid circulates and
A means for determining the temperature of the circulating fluid flowing out from the load-side heat exchanger to the air conditioning terminal, and a means for determining the temperature of the circulating fluid.
A return temperature determining means for determining the return temperature of the circulating liquid flowing into the load side heat exchanger from the air conditioning terminal is provided.
In a heat pump type chilled water cooling device that performs a cooling operation by supplying the circulating liquid cooled by the heat pump type heat source machine to the air conditioning terminal by driving the circulation pump.
The forward temperature control that controls the heat pump type heat source machine so that the forward temperature determined by the forward temperature determining means becomes the target forward temperature, or the return temperature determined by the return temperature determining means is the target return temperature. In addition to executing the return temperature control that controls the heat pump type heat source machine so as to be, a control device for increasing or decreasing the rotation speed of the compressor according to the magnitude of the load is provided.
The control device has a terminal determining means for determining the type of the air-conditioned terminal that is operated based on the operation request of the air-conditioned terminal.
When the terminal determination means determines that the radiation type terminal is operated as the air conditioner terminal during the cooling operation, the control device may use the compressor in a preset high rotation speed range. For example, the return temperature control is executed, and if the rotation speed of the compressor is in the preset medium rotation speed range, the forward temperature control is executed, and the rotation speed of the compressor is in the preset low rotation speed range. If so, execute the return temperature control and
A heat pump type chilled water cooling device, characterized in that, when the terminal determining means determines that a terminal other than the radiant terminal is operated as the air conditioning terminal, the control device executes the return temperature control.

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