WO2017138133A1

WO2017138133A1 - Hot water/cold water air-conditioning system

Info

Publication number: WO2017138133A1
Application number: PCT/JP2016/054038
Authority: WO
Inventors: 篤志河村; 進一内野; 美藤　尚文
Original assignee: 三菱電機株式会社
Priority date: 2016-02-10
Filing date: 2016-02-10
Publication date: 2017-08-17
Also published as: CN208436403U; JPWO2017138133A1; JP6537641B2

Abstract

A hot water/cold water air-conditioning system equipped with: a heat pump heat source machine having a compressor; an air conditioner; piping that forms a water circulation passage by connecting the heat pump heat source machine and the air conditioner in a circular arrangement; a water circulation pump that circulates water in the water circulation passage; a water temperature sensor that detects the temperature of the outgoing water from the heat pump heat source machine; and a control device that executes a thermo on/off control for controlling thermo on/off on the basis of the difference between a target water temperature that has been set and the temperature of the outgoing water. If it is determined that a thermo on/off cycle operation is being executed in the compressor, the control device switches to a thermo on/off suppression control. In the thermo on/off suppression control the control device sets the thermo on and thermo off operating conditions on the basis of the temperature of the refrigerant in the compressor at the time it is determined that the thermo on/off cycle operation is being executed.

Description

Hot / cold water air conditioning system

The present invention relates to a hot / cold water air conditioning system for heating or cooling a room by sending hot water or cold water generated by a heat pump heat source device to a hot / cold water air conditioner.

In a heat pump hot water heating system that performs hot water supply or heating using a heat pump cycle, hot water heated from a heat pump cycle refrigerant through a heat exchanger is supplied to an indoor radiator or hot water storage tank that performs heating, and then used. A heating hot water circulation circuit is provided for returning the hot water to the heat exchanger of the heat pump cycle. In order to control the supplied hot water, the heating hot water circulation circuit is provided with a forward temperature sensor for detecting the forward temperature of the supplied hot water.

In the conventional heat pump hot water heating system, the forward temperature control that is quick and easy to control with respect to the change of the heat pump capacity (operating frequency of the compressor) in the heat pump cycle is mainly performed. In such forward temperature control, when the efficiency of the indoor radiator on the load side of the hot water heating system is low, or when the required air conditioning hot water supply load is small, such as in the middle of the season, the heat pump cycle heat source side operates the compressor Implement frequency control and operate the compressor with minimum supply capacity. If the amount of heat supplied by the operation with this minimum supply capacity is larger than the heat radiation amount on the air conditioning hot water supply load side, the going temperature of the heating hot water circulation circuit exceeds the target going temperature. There may be a state of so-called ON / OFF cycle operation where the thermo ON / OFF is intermittently generated in a short period of time.

In the air conditioner described in Patent Document 1, in order to avoid the ON / OFF cycle operation when the supply capacity on the heat pump heat source side exceeds the air conditioning hot water supply load, the operating point temperature of the thermo ON / OFF is set. It is corrected. That is, when it is detected that the number of stoppages of the compressor within a predetermined time is increased, the preset target value of the refrigerant evaporating temperature or condensing temperature is changed, and the actual evaporating temperature or condensing temperature is changed. Control to reduce the deviation is performed. Moreover, in the air conditioning apparatus described in Patent Document 2, the thermo-off operating point temperature and the thermo-on operating point temperature set as initial values are corrected according to the duration of the thermo-off to prevent the thermo-off time from being shortened. Yes.

JP 2002-61925 A JP 2008-209029 A

In the control in the air conditioner described in Patent Literature 1 and Patent Literature 2, the extension of the thermo-ON / OFF time interval in the heat pump heat source machine is a target value or initial value that is a criterion for starting the thermo-ON / OFF operation. This is done by changing the threshold value. Therefore, there is a problem that the problem of inflow of liquid refrigerant to the compressor that may occur when the supply capacity of the heat pump heat source side exceeds the air conditioning hot water supply load and the accompanying decrease in the oil concentration of the refrigeration oil cannot be avoided. There is.

The present invention has been made in order to solve the above-described problems. Even if the supply capacity on the heat pump heat source side exceeds the air conditioning hot water supply load, the thermo pump ON / OFF cycle operation of the heat pump heat source machine is performed. It aims at preventing and suppressing the fall of the oil concentration in a compressor.

A hot / cold water air conditioning system according to the present invention includes a heat pump heat source unit having a compressor, an air conditioner that performs indoor air conditioning, a circular circulation channel that connects the heat pump heat source unit and the air conditioning unit in a ring shape, and water in the circulation channel A water circulation pump that circulates the water, a water temperature sensor that detects the temperature of water that flows out of the heat pump heat source device by the operation of the water circulation pump, and a control device that controls the thermo ON / OFF of the heat pump heat source device. When the difference between the set target water temperature and the outgoing water temperature is the first temperature difference, the device is thermo-ON, and when the difference between the target water temperature and the outgoing water temperature is the second temperature difference, the thermo ON / OFF normal control is performed. Thermo-ON / OFF suppression control for thermo-ON / OFF at a time interval longer than the thermo-ON / OFF time interval of normal control ON / OFF The thermo-ON / OFF control means to be executed and the switching means for switching from the thermo-ON / OFF normal control to the thermo-ON / OFF suppression control are executed. If the variable for counting the number of times that the thermo ON / OFF is repeated at a time interval shorter than the predetermined time interval reaches a predetermined value, the control from the thermo ON / OFF normal control to the thermo ON / OFF suppression control is performed. The thermo ON / OFF control means is forced to stop the compressor based on the refrigerant temperature in the compressor when the thermo ON / OFF normal control is switched to the thermo ON / OFF suppression control by the switching means. Set the stop time, set the third temperature difference based on the change of the incoming water temperature that occurs during the forced stop time, and forcibly stop During has passed, and the difference between the target temperature and forward water temperature and thermo-ON time of the first temperature difference, when the difference between the target temperature and forward water temperature of the third temperature difference is for thermo OFF.

According to the hot / cold water air conditioning system according to the present invention, it has been confirmed that the thermo ON / OFF cycle operation is being executed in the thermo ON / OFF suppression control that is executed after the thermo ON / OFF cycle operation state is confirmed. Set the forced stop time to forcibly stop the compressor based on the refrigerant temperature of the compressor at the time, add the passage of the forced stop time to the thermo-ON condition, and the temperature of the outgoing water temperature that occurred during the forced stop Based on the change, the operating point temperature of the thermo OFF is changed. Therefore, it is possible to suppress the thermo ON / OFF cycle operation while taking into account the operation state of the compressor. As a result, even if the minimum supply capacity of the heat pump heat source machine exceeds the required heat quantity of the air conditioning equipment, it is possible to prevent the thermo ON / OFF cycle operation and to suppress the decrease in oil concentration in the compressor. A high-efficiency and long-life hot / cold water air conditioning system can be provided.

It is a block diagram which shows schematic structure of the hot / cold water air conditioning system which concerns on Embodiment 1 of this invention. It is a refrigerant circuit figure which shows schematic structure of the heat pump heat source machine shown in FIG. It is a block diagram which shows the control apparatus of the hot / cold water air conditioning system which concerns on Embodiment 1 of this invention, and the component by which input / output is performed between this control apparatus. It is a flowchart which shows the control action of the compressor in the warm water heating operation of the warm / cold water air-conditioning system which concerns on Embodiment 1 of this invention. It is a time chart which shows the driving | running state of the compressor in warm water heating operation in the conventional warm / cold water air-conditioning system. It is a time chart which shows the driving | running state of the compressor in warm water heating operation in the warm / cold water air-conditioning system which concerns on Embodiment 1 of this invention. It is a block diagram which shows schematic structure of the hot / cold water air conditioning system which concerns on Embodiment 2 of this invention. It is a block diagram which shows schematic structure of the hot / cold water air conditioning system which concerns on Embodiment 3 of this invention.

Hereinafter, embodiments of a hot / cold water air conditioning system according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below. In the following drawings, the size of each component may be different from that of an actual apparatus.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of a hot / cold water air-conditioning system according to Embodiment 1 of the present invention. The hot / cold water air conditioning system shown in FIG. 1 includes a heat pump heat source unit 1 that can perform either hot water heating or cold water cooling, a hot / cold water air conditioner 2 (air conditioner) for indoor air conditioning, and a heat pump. The heat source unit 1 and the hot / cold water air conditioner 2 are connected in a ring to form a circulation channel, a water circulation pump 3 for circulating water in the circulation channel, and the operation of the water circulation pump 3 from the heat pump heat source unit 1 An outgoing water temperature sensor 5 for detecting the temperature of hot water or cold water flowing out (hereinafter referred to as water temperature) and a control device 6 are provided.

The hot / cold water air conditioner 2 heats or cools the indoor space according to hot water or cold water flowing from the heat pump heat source unit 1 through the pipe 4. The water circulation pump 3 rotates at a constant rotational speed when AC power is applied under the control of the control device 6. By using this water circulation pump 3, since it is not necessary to control the rotation speed of the water circulation pump 3, the control algorithm can be made relatively simple and low cost.

Here, the configuration of the heat pump heat source machine 1 will be described with reference to FIG. FIG. 2 is a refrigerant circuit diagram illustrating a schematic configuration of the heat pump heat source apparatus illustrated in FIG. 1. The heat pump heat source unit 1 includes a compressor 103, a four-way valve 104, a water heat exchanger 102, a first expansion valve 106, an intermediate pressure receiver 105, a second expansion valve 107, and an air heat exchanger 101, which are sequentially arranged. A refrigerant circuit is configured by connecting with piping. The configuration of the refrigerant circuit is an example and is not limited.

The compressor 103 includes an inverter device and the like, and finely changes the capacity for sucking and compressing the refrigerant in accordance with the operation frequency controlled by the control device 6. The four-way valve 104 switches so that the refrigerant from the compressor 103 flows into the water heat exchanger 102 during the hot water heating operation, and switches so that the refrigerant from the air heat exchanger 101 is sucked into the compressor 103. The four-way valve 104 switches so that the refrigerant from the compressor 103 flows into the air heat exchanger 101 during the cold water cooling operation, and switches so that the refrigerant from the water heat exchanger 102 is sucked into the compressor 103. The switching of the four-way valve 104 is performed by the control device 6.

The water heat exchanger 102 performs heat exchange between the refrigerant flowing in the refrigerant circuit and the water flowing in the pipe. This water heat exchanger 102 acts as a radiator (condenser) during the hot water heating operation, and heats the water flowing in the piping. Further, the water heat exchanger 102 acts as a heat absorber (evaporator) during the cold water cooling operation, and cools the water flowing in the piping. In the first embodiment, the water heat exchanger 102 is built in the heat pump heat source unit 1. However, for example, the water heat exchanger 102 may be provided separately from the heat pump heat source unit 1. The hot / cold water air conditioner 2 may be provided.

The first expansion valve 106 adjusts the flow rate of the refrigerant to adjust (depressurize) the pressure of the refrigerant flowing through the water heat exchanger 102, for example. The intermediate pressure receiver 105 is provided between the first expansion valve 106 and the second expansion valve 107 in the refrigerant circuit, and accumulates excess refrigerant in the refrigerant circuit. A suction pipe connected from the four-way valve 104 to the suction side of the compressor 103 passes through the intermediate pressure receiver 105. The intermediate pressure receiver 105 can exchange heat between the refrigerant passing through the suction pipe and the surplus refrigerant, and has a function as an internal heat exchanger.

Also, the second expansion valve 107 adjusts the pressure by adjusting the flow rate of the refrigerant in the same manner as the first expansion valve 106. As the first expansion valve 106 and the second expansion valve 107, an electronic expansion valve capable of changing the opening degree of the valve based on an instruction from the control device 6 is used. The air heat exchanger 101 is, for example, a fin-and-tube heat exchanger that performs heat exchange between refrigerant and outside air sent by a blower. The air heat exchanger 101 acts as a heat absorber (evaporator) during hot water heating operation, and acts as a radiator (condenser) during cold water cooling operation.

As the refrigerant flowing through the refrigerant circuit of the heat pump heat source apparatus 1, for example, either R410A or R407C which is an HFC mixed refrigerant, or R32 which is an HFC single refrigerant having a low global warming potential may be used. Good. Instead of these, either a hydrofluoroolefin-based refrigerant (HFO1234yf, HFO1234ze, etc.), an HC-based R290 (propane) or R1270 (propylene) single or mixed refrigerant may be used.

The above-described control device 6 controls the ON / OFF operation of the compressor 103 and the operation frequency of the compressor 103 based on the water temperature detected by the outgoing water temperature sensor 5. Further, the control device 6 is based on the indoor set temperature set by the user's remote control operation, the indoor temperature obtained by the air conditioning of the hot / cold water air conditioner 2, the water temperature detected by the outgoing water temperature sensor 5, and the like. 1 operation is controlled.

The water cycle when the hot water heating operation or the cold water cooling operation is performed in the hot / cold water air conditioning system configured as described above will be described. In the hot water heating operation, water circulates between the heat pump heat source unit 1 and the hot / cold water air conditioner 2 by the water circulation pump 3 that rotates at a constant rotational speed. Circulating water discharged from the water circulation pump 3 flows into the heat pump heat source unit 1 and is heated while passing through the water heat exchanger 102 of the heat pump heat source unit 1. The heated hot water of the circulating water is supplied to the hot / cold water air conditioner 2 to exchange heat (radiate heat) with the air in the room to heat the room. Then, the hot water whose temperature has been lowered by the heat exchange is again sucked into the water circulation pump 3 and sent to the heat pump heat source unit 1 for circulation.

In the cold water cooling operation, the circulating water discharged from the water circulation pump 3 is cooled by the water heat exchanger 102 of the heat pump heat source unit 1. The cooled chilled water is supplied to the hot / cold water air conditioner 2 and exchanges heat with the room air (heat absorption) to cool the room. Then, the cold water whose temperature has been raised by the heat exchange is again sucked into the water circulation pump 3 and sent to the heat pump heat source unit 1 for circulation.

FIG. 3 is a block diagram showing the control device of the hot / cold water air-conditioning system according to Embodiment 1 and the components that perform input / output between the control device. The control device 6 includes a thermo ON / OFF control means 61, a switching means 62, and a return means 63. The thermo ON / OFF control means 61 is configured to perform thermo ON / OFF normal control in which the thermo ON / OFF is repeated at predetermined time intervals based on the incoming water temperature input from the outgoing water temperature sensor 5, and the thermo ON / OFF is predetermined. Thermo ON / OFF suppression control executed at a time interval longer than the time interval is executed. The switching means 62 performs switching from the thermo ON / OFF normal control to the thermo ON / OFF suppression control based on the outgoing water temperature input from the outgoing water temperature sensor 5 and the operating frequency of the compressor 103. The return means 63 performs a return from the thermo ON / OFF suppression control to the thermo ON / OFF normal control based on the incoming water temperature and the operating frequency of the compressor 103.

Next, the control of the compressor 103 in the hot water heating operation in this hot / cold water air conditioning system will be described with reference to FIG. FIG. 4 is a flowchart showing the control operation of the compressor in the hot water heating operation of the hot / cold water air conditioning system according to the first embodiment. The control shown in the flowchart of FIG.

First, the control device 6 drives the four-way valve 104 to connect the discharge side of the compressor 103 and the water heat exchanger 102, and connects the air heat exchanger 101 and the suction side of the compressor 103. Next, the control device 6 drives the compressor 103 to discharge the refrigerant and circulates in the refrigerant circuit. And the control apparatus 6 rotates the water circulation pump 3 with a fixed rotational speed, circulates the water in the piping 4, and starts the driving | operation of warm water heating.

Thereafter, the thermo ON / OFF control means 61 of the control device 6 starts the thermo ON / OFF normal control of the compressor 103 in step S1. First, the thermo ON / OFF control means 61 reads the water temperature detected by the incoming water temperature sensor 5, and then compares the read water temperature with the target water temperature to control the thermo ON / OFF and operating frequency of the compressor 103. To do. This target water temperature is, for example, a value set by a user's remote control operation. If the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 is equal to or lower than the target outgoing water temperature Tt−T1 (first temperature difference, for example, 0.5 deg), the thermo is turned ON. On the other hand, if the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 is equal to or higher than the target outgoing water temperature Tt + T2 (second temperature difference, for example, 2 deg), the thermo is turned off.

In the first embodiment, the switching determination to the thermo ON / OFF suppression control is performed during the operation by the thermo ON / OFF normal control in step S1. The contents will be described below. In step S2, the switching unit 62 checks whether or not the operating frequency of the compressor 103 of the heat pump heat source apparatus 1 is the minimum frequency (for example, 25 Hz). If it is confirmed that the operating frequency of the compressor 103 is not the minimum frequency, the process proceeds to step S3. The fact that the compressor 103 is operated at a frequency higher than the minimum frequency can be determined that the minimum supply capacity of the heat pump heat source unit 1 does not exceed the amount of heat required for the hot / cold water air conditioner 2. Therefore, in step S3, the determination count number Ncount, which is a variable used for switching determination from the thermo-ON / OFF normal control to the thermo-ON / OFF suppression control, is reset to zero. The determination count number Ncount is a variable that is incremented by 1 when the switching of the thermo ON / OFF in a short time is detected. The switching unit 62 resets the determination count number Ncount to zero. Thereafter, the control returns to step S1, and the thermo ON / OFF normal control by the thermo ON / OFF control means 61 is continued.

If it is confirmed in step S2 that the operating frequency of the compressor 103 is the minimum frequency, the process proceeds to step S4. In step S4, the switching means 62 checks whether or not the thermo is turned off within a predetermined time TA (first predetermined time, for example, 10 minutes) after the thermo is turned on. If the time interval from the thermo-ON to the thermo-OFF is longer than the predetermined time TA, that is, that the operation by the thermo-ON has exceeded the predetermined time TA, it can be determined that the thermo-ON / OFF cycle operation is not in the state. Therefore, if it is confirmed that the thermo is not turned off within the predetermined time TA after the thermo is turned on, the process proceeds to step S3, and the determination count number Ncount is reset to zero. Thereafter, the control returns to step S1, and the thermo ON / OFF normal control by the thermo ON / OFF control means 61 is continued.

If it is confirmed in step S4 that the thermo is turned off within a predetermined time TA after the thermo is turned on, the process proceeds to step S5. In the case of proceeding to step S5, in the state where the required heat quantity of the hot / cold water air conditioner 2 is smaller than the operation capacity at the minimum frequency of the compressor 103, the thermo OFF is performed before the predetermined time TA has elapsed from the thermo ON. This is the case. In step S5, it is checked whether or not the determination count number Ncount is zero. If the determination count number Ncount is not zero, the process proceeds to step S6.

In step S6, the switching unit 62 checks whether or not a predetermined time TB (second predetermined time, for example, 10 minutes) has elapsed since 1 was added to the determination count number Ncount last time. When it is confirmed in step S6 that the predetermined time TB has not elapsed, it is confirmed that the time from the thermo ON to the thermo OFF is shorter than the predetermined time TA before the predetermined time TB elapses. This is a case where it is confirmed that the time from the thermo ON again to the thermo OFF is shorter than the predetermined time TA. That is, the thermo ON / OFF cycle operation may be started. Therefore, in this case, the process proceeds to step S7, and 1 is added to the determination count number Ncount.

When it is confirmed in step S6 that the predetermined time TB has elapsed, it is confirmed that the time from the thermo ON to the time when the thermo is turned off is shorter than the predetermined time TA, and then from the thermo ON again. This is a case where the predetermined time TB has elapsed until it is confirmed that the time until the thermo-OFF is shorter than the predetermined time TA. Therefore, it is determined that there is no thermo-ON / OFF cycle operation. Therefore, in this case, the process proceeds to step S3, and the switching unit 62 resets the determination count number Ncount to zero. Thereafter, the control returns to step S1, and the thermo ON / OFF normal control by the thermo ON / OFF control means 61 is continued.

On the other hand, if it is confirmed in step S5 that the determination count number Ncount is zero, the process of step S6 is skipped and the process of step S7 is executed. In step S5, although thermo-ON / OFF is not repeated in a short time, thermo-OFF is confirmed within a predetermined time TA from thermo-ON, and thermo-ON / OFF cycle operation may have started. There is. Therefore, in this case, the process of step S6 is not performed, and 1 is added to the determination count number Ncount in step S7.

After the process of step S7, the process proceeds to step S8, and the switching means 62 checks whether or not the determination count number Ncount is equal to or greater than a predetermined number. The case where the determination count number Ncount is less than a certain number is a case where the thermo-ON / OFF in a short time does not occur frequently in a state where the compressor 103 is operated at the lowest frequency. This is a case where the vehicle is not in the OFF cycle operation state. In this case, it is determined that even if the thermo-ON / OFF normal control is continued, the life of each component constituting the refrigerant circuit is not affected, and the problem of suction of the liquid refrigerant in the compressor 103 does not occur. it can. Therefore, if the determination count number Ncount is less than the predetermined number, the control returns to step S1, and the thermo-ON / OFF normal control by the thermo-ON / OFF control means 61 is continued.

On the other hand, when the determination count number Ncount has reached a certain number, when the compressor 103 is operated at the lowest frequency, switching from the thermo-ON to the thermo-OFF and switching from the thermo-OFF to the thermo-ON This is a case where the process is repeatedly executed at time intervals equal to or less than predetermined times TA and TB. That is, it is determined that the thermo ON / OFF cycle operation is being performed. In this case, if the thermo-ON / OFF normal control is continued, the life of each component constituting the refrigerant circuit may be affected, and the liquid refrigerant may be sucked into the compressor 103. Therefore, the switching means 62 performs switching from the thermo ON / OFF normal control to the thermo ON / OFF suppression control. When it is confirmed that the determination count number Ncount has reached a certain number, the process proceeds to step S9, and thermo-ON / OFF suppression control by the thermo-ON / OFF control means 61 is started.

Steps S2 to S8 described above are processing procedures executed by the switching means 62, and a process for determining switching to the thermo ON / OFF suppression control while the thermo ON / OFF normal control is being performed. It is a procedure. The thermo ON / OFF control means 61 performs the following control. After the thermo-ON, when the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 does not reach the target outgoing water temperature Tt + T2, and the difference is large, the thermo ON / OFF control means 61 changes the operating frequency of the compressor 103. Increase the heat supply. If the heating capacity of the heat pump heat source device 1 becomes larger than the heat radiation amount of the hot / cold water air conditioner 2 by this control, the forward water temperature detection temperature Tm detected by the forward water temperature sensor 5 rises. When the outgoing water temperature detection temperature Tm reaches the target outgoing water temperature Tt, the thermo-ON / OFF control means 61 adjusts the compressor 103 so that the supply capacity of the heat pump heat source unit 1 and the heat radiation amount of the hot / cold water air conditioner 2 are balanced. Reduce the operating frequency gradually to maintain the temperature of the incoming water temperature.

At this time, even if the operating frequency of the compressor 103 becomes the minimum frequency (for example, 25 Hz), if the outgoing water temperature detection temperature Tm by the outgoing water temperature sensor 5 continues to rise and becomes thermo OFF, the minimum frequency of the heat pump heat source machine 1 It can be considered that the minimum supply capacity in operation is larger than the heat radiation amount of the hot / cold water air conditioner 2.

When the compressor 103 is stopped by the thermo OFF, the supply capacity of the heat pump heat source unit 1 becomes zero. As a result, when the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 decreases and becomes equal to or lower than the target outgoing water temperature Tt−T1 again, the thermo-ON is performed. However, even if the thermo is turned on, the minimum supply capability in the minimum frequency operation of the heat pump heat source apparatus 1 is larger than the heat radiation amount of the hot / cold water air conditioner 2, so the thermo pump is turned off again. That is, when the minimum supply capability in the minimum frequency operation of the heat pump heat source device 1 is larger than the heat radiation amount of the hot / cold water air conditioner 2, the thermo ON (the compressor 103 is operated at the minimum frequency) and the thermo OFF (the compressor 103 is stopped). The thermo-ON / OFF cycle operation is repeated intermittently in a short cycle.

The switching means 62 determines whether or not the ON / OFF cycle operation has been performed within a certain period of time by the processes in steps S2 to S8 described above.

The thermo ON / OFF suppression control executed in step S9 will be described. In the thermo ON / OFF suppression control, the thermo ON / OFF control means 61 forcibly stops the compressor 103 without comparing the forward water temperature detection temperature Tm detected by the forward water temperature sensor 5 with the target forward water temperature Tt. Set the stop time α. The forced stop time α is, for example, 10 minutes. Then, after the elapse of the forced stop time α, the outgoing water temperature detection temperature Tm is compared with the target outgoing water temperature Tt. The thermo ON / OFF control means 61 performs thermo ON when the outgoing water temperature detection temperature Tm becomes equal to or lower than the target outgoing water temperature Tt−T1. On the other hand, when the outgoing water temperature detection temperature Tm is equal to or higher than the target outgoing water temperature Tt + the predetermined threshold T3 (third temperature difference, for example, 5 deg), the thermo-OFF is performed.

The forced stop time α of the compressor 103 set in the thermo-ON / OFF suppression control is the refrigerant temperature (for example, the compressor) when the determination count number Ncount reaches a certain number during the thermo-ON operation. 103). In other words, it is determined by the refrigerant temperature in the compressor 103 when the switching means 62 switches from the thermo ON / OFF normal control to the thermo ON / OFF suppression control. When the refrigerant temperature is relatively high, the forced stop time α is set to be relatively long. Further, when determining whether to perform the thermo-off in the thermo-ON / OFF suppression control, the threshold T3 used for comparing the forward water temperature detection temperature Tm and the target forward water temperature Tt is the value after the thermo-ON / OFF suppression control is started. When the first thermo OFF is confirmed, it is set according to the degree of decrease in the going water temperature during the forced stop time α. In other words, in the thermo ON / OFF suppression control, the operating point temperature of the thermo OFF is corrected based on the degree of decrease in the outgoing water temperature during the forced stop time α. Therefore, if the refrigerant temperature is relatively high and the forced stop time α is set to be long, the drop in the going water temperature becomes larger, so the threshold T3 is set high. The forced stop time α and the threshold value T3 differ depending on the performance of the heat pump heat source apparatus 1, and therefore, the forced stop time α and the threshold value T3 are set based on a result of a test that actually generates a thermo ON / OFF cycle operation.

Further, in the thermo ON / OFF suppression control, the forward water temperature detection temperature Tm detected by the forward water temperature sensor 5 is compared with the forward water temperature upper limit value Tx, and when the forward water temperature detection temperature Tm exceeds the forward water temperature upper limit value Tx, The thermo ON / OFF control means 61 executes a process for stopping the compressor 103. The forward water temperature upper limit value Tx is set by the user using a remote controller or the like. This process prevents the hot water having a temperature higher than the allowable upper limit temperature from flowing into the hot / cold water air conditioner 2 due to the high temperature of the outgoing water, thereby preventing malfunction of the operation of the hot / cold water air conditioner 2.

In the first embodiment, during the operation by the thermo-ON / OFF suppression control in step S9, the return means 63 performs the return determination to the thermo-ON / OFF normal control. The contents will be described below. In step S10, the return means 63 determines whether or not the compressor 103 is continuously operating at a frequency higher than the minimum operating frequency for a predetermined time (third predetermined time) (for example, the minimum operating frequency is 25 Hz and the predetermined time If it is 60 minutes, it is checked whether or not it is continuously operating at 26 Hz for 60 minutes). When the return means 63 confirms that the operating frequency of the compressor 103 is the lowest frequency, the control returns to step S9 again and the thermo ON / OFF suppression control by the thermo ON / OFF control means 61 is continued.

When the compressor 103 is continuously operating at a frequency higher than the minimum operating frequency for a predetermined time, the minimum supply capacity of the heat pump heat source unit 1 is less than the heat dissipation amount of the hot / cold water air conditioner 2, and the thermo ON / OFF Even if the normal control is performed, it can be determined that the possibility of the thermo-ON / OFF cycle operation is low. Accordingly, in this case, the process proceeds to step S3, and the return means 63 resets the determination count number Ncount to zero, returns to step S1, and controls the thermo ON / OFF control means 61 from the thermo ON / OFF suppression control to the thermo ON. / OFF Return to normal control.

Here, the difference between the operation state of the conventional compressor and the operation state of the compressor in the first embodiment will be described with reference to FIGS. FIG. 5 is a time chart showing the operating state of the compressor in the hot water heating operation in the conventional hot / cold water air conditioning system, and FIG. 6 is the time showing the operating state of the compressor in the hot water heating operation in the hot / cold water air conditioning system according to Embodiment 1. It is a chart. The time chart of FIG. 5 and FIG. 6 has shown the driving | running state in case the minimum supply capability of a heat pump heat source machine is larger than the thermal radiation amount of a hot / cold water air conditioner. That is, FIG. 5 shows the change in water temperature and the operating state of the compressor 103 when the thermo ON / OFF suppression control according to the first embodiment (the processing in step S9 described above) is performed.

In the operation of the conventional compressor 103, only the thermo ON / OFF normal control is executed as shown in FIG. Since the responsiveness of the water temperature detected by the going water temperature sensor 5 is fast, the water temperature becomes equal to or higher than the target water temperature immediately after the thermo-ON, and the thermo-OFF (operation of the compressor 103 of the heat pump heat source unit 1 is stopped). Even if the compressor 103 is stopped, the water circulation pump 3 is driven and the circulating water flows. Therefore, after the thermo is turned off, the water temperature soon becomes lower than the target water temperature, and the thermo is turned on. That is, the compressor 103 is in a thermo ON / OFF cycle operation, and the heat pump heat source unit 1 is in an ON / OFF operation.

In contrast, in the first embodiment, when the thermo ON / OFF at a short time interval reaches a predetermined number of times and the thermo ON / OFF cycle operation is detected, the thermo ON / OFF normal control suppresses the thermo ON / OFF normal control. Switch to control. In the thermo ON / OFF suppression control, when the operation is switched to the thermo ON / OFF suppression control, that is, when the thermo ON / OFF reaches a predetermined number of times, the forced stop time is based on the refrigerant temperature such as the suction heating degree of the compressor 103, for example. Is set. Then, the passage of the forced stop time is added to the condition for turning on the thermo. Furthermore, the operating point temperature of the thermo OFF after the next time is corrected based on the temperature drop of the outgoing water temperature that occurs during the forced stop time. As a result, it is possible to extend the thermo-ON / OFF time interval and reduce the number of thermo-ON / OFF times without impairing the comfort of air conditioning.

Although the case where the hot water heating operation is performed in the first embodiment has been described, the switching between the thermo ON / OFF normal control and the thermo ON / OFF suppression control is also performed in the cold water cooling operation in the same processing procedure as the flowchart shown in FIG. Executed. In the cold water cooling operation, the refrigerant flow is reversed from that in the hot water heating operation by switching the four-way valve 104. That is, the air heat exchanger 101 acts as a radiator (condenser), and the water heat exchanger 102 acts as a heat absorber (evaporator) to cool the water flowing through the water heat exchanger 102.

In the thermo-ON / OFF normal control in the cold water cooling operation, the controller 6 detects the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 to be equal to or higher than the target outgoing water temperature Tt + T4 (first temperature difference, for example, T4 = 0.5 deg). At this time, the thermo is turned ON, and when the outgoing water temperature detection temperature Tm detected by the outgoing water temperature sensor 5 is equal to or lower than the target outgoing water temperature Tt−T5 (second temperature difference, for example, T5 = 2 deg), the thermo is turned OFF. Switching from the thermo-ON / OFF normal control to the thermo-ON / OFF suppression control in the cold water cooling operation is performed in the same manner as in steps S2 to S8 described above. Thermo ON / OFF suppression control in the cold water cooling operation is executed in the same manner as in step S9 described above. The forced stop time is set based on the refrigerant temperature of the compressor 103 when the thermo ON / OFF reaches a predetermined number of times. The passage of the forced stop time of the compressor 103 is added to the condition of the thermo ON, and the operating point temperature of the thermo OFF after the next time is corrected based on the temperature rise of the forward water temperature that occurs during the forced stop time.

As described above, in the hot / cold water air-conditioning system according to the first embodiment, the control device 6 has the minimum supply capacity of the heat pump heat source unit 1 exceeding the amount of heat dissipation or heat absorption required by the hot / cold water air-conditioning equipment 2. When intermittent switching of thermo ON / OFF in a short time is detected, the thermo ON / OFF normal control is switched to the thermo thermo ON / OFF suppression control, while the minimum supply capacity of the heat pump heat source unit 1 is hot / cold water air conditioning equipment When it is detected that the heat dissipation amount or the heat absorption amount required by 2 is lower, the operation is switched from the thermo ON / OFF suppression control to the thermo ON / OFF normal control. In the thermo-ON / OFF suppression control, conditions for thermo-ON and thermo-OFF are set based on the refrigerant temperature of the compressor 103 when it is determined that the thermo-ON / OFF cycle operation is in progress. Therefore, even when the minimum supply capacity of the heat pump heat source device 1 is larger than the heat dissipation amount in the case of hot water heating of the hot / cold water air conditioner 2 or the heat absorption amount in the case of cold water cooling, the thermo-ON / OFF cycle operation can be suppressed. As a result, the thermo ON / OFF cycle operation can be prevented, and the decrease in the oil concentration in the compressor 103 can be suppressed, and a high-efficiency and long-life hot / cold water air conditioning system can be provided.

Embodiment 2. FIG.
FIG. 7 is a block diagram showing a schematic configuration of a hot / cold water air-conditioning system according to Embodiment 2 of the present invention. The second embodiment includes an auxiliary heater 7 that heats the circulating water between the heat pump heat source unit 1 and the outgoing water temperature sensor 5 in the hot / cold water air conditioning system of the first embodiment. In the hot water heating operation, when the supply capacity of the heat pump heat source unit 1 is insufficient, the circulating water is heated using the auxiliary heater 7 as an auxiliary heat source. Power supply to the auxiliary heater 7 is performed by the control device 6.

In the second embodiment, the control operation of the compressor 103 in the hot water heating operation or the cold water cooling operation is the same as the flowchart shown in FIG. That is, the control device 6 performs intermittent switching of the thermo ON / OFF in a short time in a state where the minimum supply capacity of the heat pump heat source unit 1 exceeds the amount of heat dissipation or heat absorption required by the hot / cold water air conditioner 2. If detected, the thermo-ON / OFF normal control is switched to the thermo-ON / OFF suppression control. Further, when it is detected that the minimum supply capacity of the heat pump heat source unit 1 is below the amount of heat dissipation or heat absorption required by the hot / cold water air conditioner 2, the thermo ON / OFF suppression control is switched to the thermo ON / OFF normal control. Then, in the thermo ON / OFF suppression control, the control device 6 determines the conditions for the thermo ON and the thermo OFF based on the refrigerant temperature of the compressor 103 at the time when it is determined that the thermo ON / OFF cycle operation is in progress. Set.

Therefore, even if the minimum supply capacity of the heat pump heat source unit 1 by controlling the operation frequency of the compressor 103 is larger than the heat dissipation amount in the case of hot water heating of the hot / cold water air conditioner 2 or the heat absorption amount in the case of cold water cooling, the compressor The thermo-ON / OFF cycle operation can be suppressed in a state where the operation state 103 is taken into consideration, and the same effect as in the first embodiment can be obtained.

Embodiment 3 FIG.
FIG. 8 is a block diagram illustrating a schematic configuration of the hot / cold water air-conditioning system according to the third embodiment. The third embodiment includes the hot water storage tank 9 in which the heat exchanger 8 is built in the hot / cold water air conditioning system of the second embodiment. One end of the heat exchanger 8 is connected to the branch pipe 12a (branch point) inserted in the pipe 4 between the auxiliary heater 7 and the hot / cold water air conditioner 2 via the pipe 12, and the other end of the heat exchanger 8 is connected. Is connected via a pipe 12 to an electric three-way valve 11 (confluence) inserted in a pipe 4 between the water circulation pump 3 and the hot / cold water air conditioner 2. That is, the hot water storage tank 9 is connected in parallel to the hot / cold water air conditioner 2 via the pipe 12. In addition, a tank water temperature sensor 10 for detecting the water temperature in the hot water storage tank 9 heated by the heat exchanger 8 is attached to the hot water storage tank 9.

The control device 6 according to the third embodiment selects one of the hot water heating operation, the cold water cooling operation, and the hot water supply operation in accordance with, for example, a user's remote control operation. In the hot water heating operation or the cold water cooling operation, the control device 6 drives the electric three-way valve 11 so that water (hot water or cold water) circulates between the heat pump heat source unit 1 and the hot / cold water air conditioner 2 as described above. To do. Moreover, the control apparatus 6 drives the electric three-way valve 11 so that warm water circulates between the heat pump heat source unit 1 and the heat exchanger 8 during the hot water supply operation.

In the third embodiment, the operation of the compressor 103 in the operation of the hot water heating operation or the cold water cooling operation and the operation of the hot water supply operation is the same as the flowchart shown in FIG. 4, and the second embodiment has been described above. Street. Therefore, even if the minimum supply capacity of the heat pump heat source unit 1 by controlling the operation frequency of the compressor 103 is larger than the heat dissipation amount in the case of hot water heating of the hot / cold water air conditioner 2 or the heat absorption amount in the case of cold water cooling, the compressor The thermo-ON / OFF cycle operation can be suppressed in a state where the operation state 103 is taken into account, and the same effect as in the first and second embodiments can be obtained.

In the third embodiment, the auxiliary heater 7 is provided between the heat pump heat source unit 1 and the hot / cold water air conditioner 2, but the present invention is not limited to this. It is good also as a structure which connects the heat pump heat source machine 1 and the hot / cold water air-conditioning apparatus 2 without going through the auxiliary heater 7.

In the first to third embodiments, the control device 6 repeats the state where the minimum supply capacity of the heat pump heat source unit 1 is larger than the required heat amount of the hot / cold water air conditioner 2 and the thermo ON / OFF is shorter than a predetermined time interval. Has reached the predetermined number of times, the thermo-ON / OFF normal control is switched to the thermo-ON / OFF suppression control. Therefore, even when the minimum supply capacity of the heat pump heat source device 1 is larger than the required heat quantity of the hot / cold water air conditioner 2, it is possible to prevent the thermo ON / OFF cycle operation.

In the first to third embodiments, the thermo-ON / OFF control means 61 of the control device 6 has a relatively high refrigerant temperature in the compressor 103 when it is determined that the thermo-ON / OFF cycle operation is being performed. When the forced stop time is set relatively long. As a result, the threshold value corrected based on the changed outgoing water temperature during the forced stop time also becomes relatively large. That is, the thermo-ON condition and the thermo-OFF operating point are set in consideration of the operation state of the compressor 103. Therefore, in the thermo ON / OFF suppression control, the thermo ON / OFF time interval can be extended, and the inflow of liquid refrigerant in the compressor 103 and the accompanying decrease in the oil concentration of the refrigerating machine oil can be prevented.

The switching means 62 is operated when the operation frequency of the compressor 103 is not the minimum frequency in the operation with the thermo-ON, when the operation with the thermo-ON continues for a predetermined time TA, and until the thermo-ON is turned off. Each time when the predetermined time TB has elapsed from when it is confirmed that the time is shorter than the predetermined time TA until when it is confirmed that the time from the thermo ON to the thermo OFF again is shorter than the predetermined time TA. In this case, the determination count number Ncount is reset and the thermo-ON / OFF normal control is continued. Therefore, switching from the thermo-ON / OFF normal control to the thermo-ON / OFF suppression normal control can be executed accurately.

In the first to third embodiments, during the execution of the thermo-thermo ON / OFF suppression control, the return means 63 is such that the compressor 103 of the heat pump heat source unit 1 operates at an operating frequency higher than the minimum operating frequency, for example, for 60 minutes. When operating continuously, the thermo ON / OFF suppression control is switched to the thermo ON / OFF normal control. Therefore, the end of the thermo ON / OFF suppression control can be accurately executed.

1 heat pump heat source machine, 2 hot / cold water air conditioning equipment, 3 water circulation pump, 4 piping, 5 outgoing water temperature sensor, 6 control device, 7 auxiliary heater, 8 heat exchanger, 9 hot water storage tank, 10 tank water temperature sensor, 11 electric three-way valve, 12 piping, 12a branch pipe, 61 thermo ON / OFF control means, 62 switching means, 63 return means, 101 air heat exchanger, 102 water heat exchanger, 103 compressor, 104 four-way valve, 105 medium pressure receiver, 106th 1 expansion valve, 107 second expansion valve.

Claims

A heat pump heat source machine having a compressor;
Air conditioning equipment for air conditioning indoors;
A circulating water channel in which the heat pump heat source unit and the air conditioner are connected in an annular shape;
A water circulation pump for circulating water in the circulation channel,
A water temperature sensor that detects a forward water temperature that is a temperature of water flowing out of the heat pump heat source device by operation of the water circulation pump;
A control device for controlling thermo ON / OFF of the heat pump heat source machine,
The control device includes:
Thermo-ON / OFF normal control that is thermo-ON when the difference between the set target water temperature and the forward water temperature is a first temperature difference, and thermo-OFF when the difference between the target water temperature and the forward water temperature is a second temperature difference; Thermo-ON / OFF control means for performing thermo-ON / OFF suppression control for thermo-ON / OFF at a time interval longer than the thermo-ON / OFF time interval of the thermo-ON / OFF normal control;
Switching means for switching from the thermo ON / OFF normal control to the thermo ON / OFF suppression control,
In the switching means, a variable for counting the number of times that the minimum supply capacity of the heat pump heat source device is larger than the required heat amount of the air conditioner and the thermo ON / OFF is repeated at a time interval shorter than a predetermined time interval is a predetermined value. Is reached, switching from the thermo-ON / OFF normal control to the thermo-ON / OFF suppression control is performed.
The thermo ON / OFF control means is:
Based on the refrigerant temperature in the compressor when the thermo ON / OFF normal control is switched to the thermo ON / OFF suppression control by the switching means, a forced stop time for stopping the compressor is set, and the forced A third temperature difference is set based on a change in the outgoing water temperature that occurs during the stop time, the forced stop time has elapsed, and the difference between the target water temperature and the outgoing water temperature is the first temperature difference A hot / cold water air conditioning system in which the thermo is turned on and the thermo is turned off when the difference between the target water temperature and the outgoing water temperature is the third temperature difference.
The thermo ON / OFF control means, when the switching means switches from the thermo ON / OFF normal control to the thermo ON / OFF suppression control, when the refrigerant temperature in the compressor is relatively high, The hot / cold water air conditioning system according to claim 1, wherein the stop time is set to be relatively long.
The switching means determines that the time from the thermo-ON to the thermo-OFF again before the second predetermined time elapses after it is confirmed that the time from the thermo-ON to the thermo-OFF is shorter than the first predetermined time. The hot / cold water air conditioning system according to claim 1 or 2, wherein the variable is incremented by 1 when it is confirmed that the time is shorter than the first predetermined time.
The switching means is configured such that when the operation frequency of the compressor is not the minimum frequency in the operation by the thermo-ON, the operation by the thermo-ON is continued after the first predetermined time, and the thermo-ON to the thermo-OFF Until it is confirmed that the time from when the thermo is turned on to when the thermo is turned off again is shorter than the first predetermined time after it is confirmed that the time until the time is shorter than the first predetermined time. The hot / cold water air conditioning system according to claim 3, wherein the variable is reset in each case when a predetermined time of elapses.
The control device further includes return means for returning from the thermo-ON / OFF suppression control to the thermo-ON / OFF normal control,
The return means is continuously operated for a third predetermined time at an operating frequency higher than a minimum operating frequency during execution of the thermo ON / OFF suppression control by the thermo ON / OFF control means. The hot / cold water air-conditioning system according to any one of claims 1 to 4, wherein when operating, the thermo-ON / OFF suppression control is returned to the thermo-ON / OFF normal control.
The hot / cold water air conditioning system according to any one of claims 1 to 5, wherein an auxiliary heat source is provided between the heat pump heat source device and the water temperature sensor in the circulation channel.
In the circulation channel,
A hot water storage tank having a heat exchanger connected between the water temperature sensor and the air conditioner as a branch point, a junction between the air conditioner and the water circulation pump, connected in parallel to the air conditioner, and
A tank water temperature sensor for detecting the water temperature in the hot water storage tank;
A three-way valve that is provided at either the branch point or the junction point and switches the water circulated by the circulation pump to flow to either the air conditioner side or the hot water storage tank side. The hot / cold water air conditioning system according to claim 1.