JP5481838B2 - Heat pump cycle equipment - Google Patents

Description

  The present invention relates to a heat pump cycle device that adjusts a heating capacity for heating a fluid to be heated.

2. Description of the Related Art Conventionally, there is known a heat pump cycle device configured to be able to switch operation modes such as a hot water supply operation mode for heating hot water and a heating operation mode for heating a house (for example, Patent Document 1). In this Patent Document 1, compression is performed so that the predetermined capacity of the heat pump cycle in the heat pump cycle device can be exhibited and maintained with appropriate efficiency so that the temperature of the fluid to be heated becomes the target heating temperature set in each operation mode. The rotation speed of the machine and the opening degree of the expansion valve are controlled.
JP 2008-111657 A

  By the way, in the heat pump cycle device configured to be able to switch the operation mode, for example, when it is necessary to raise the heating target fluid to a high temperature as in the hot water supply operation mode, the heating target fluid is raised to the target heating temperature. Even if the coefficient of performance (COP) of the heat pump cycle becomes low, the heating capacity of the heat pump cycle device must be kept constant.

  On the other hand, when it is necessary to raise the fluid to be heated to an intermediate temperature lower than the high temperature in the hot water supply operation mode, for example, in the heating operation mode, the heating capacity is appropriately controlled while exhibiting a high COP. It is desirable to operate the cycle device.

  However, in Patent Document 1, without considering the difference in heating capacity required in each of these operation modes, a compressor is simply used so that the “predetermined capacity of the heat pump cycle can be exhibited and maintained with appropriate efficiency. Only the control of the frequency and the opening degree of the expansion valve ”is disclosed, and no specific means for improving the COP of the heat pump cycle is disclosed.

  In view of the above points, an object of the present invention is to specifically improve the COP of a heat pump cycle in an operation mode in which it is desirable to operate while exhibiting a high COP.

In order to achieve the above object, according to the first aspect of the present invention, the compressor (11) for sucking and compressing the refrigerant, and the heating heat for heating the fluid to be heated by the high-pressure refrigerant discharged from the compressor (11). Heat exchanger having an exchanger (12), a decompression means (13) for decompressing the high-pressure refrigerant that has passed through the heating heat exchanger (12), and an evaporator (14) for evaporating the low-pressure refrigerant decompressed by the decompression means (13) (10), a heating capacity adjusting means (40) for adjusting a heating capacity for heating the fluid to be heated, a circulation circuit (20) for circulating the fluid to be heated, and a hot water circulation circuit for circulating hot water in the hot water storage tank and (30), a mode switching means for switching the operating mode (45), comprising a, in the first operation mode, the heating capacity increases the degree when increasing the heating capacity with decreasing ambient temperature, Hitopo When the heat load of the Pusaikuru (10) is when the low heat load as a high heat load and is configured to be changed, the mode switching means (45), the increase heating capacity with decreasing outdoor air temperature 1 operation mode and 2nd operation mode which maintains heating capability uniformly irrespective of the change of outside temperature are comprised so that switching is possible, and the circulation circuit heats by heat-dissipating the heat | fever of the heating object fluid The heating device (23), the heat exchanger (24) for exchanging heat of the heating target fluid with hot water, and the heating side fluid (20a) for circulating the heating target fluid to the heating device (23) And a flow path switching means (22a) for switching to the hot water supply side path (20b) for circulating the fluid to be heated in the heat exchanger (24), and the flow path switching means (22a) is provided in the first operation mode. Circulation of fluid to be heated Switch the road to the heating side path (20a), characterized in that the circulation path of the heated subject fluid to the second operation mode is configured to switch to the hot water supply side path (20b).

  According to this, in the first operation mode, since the heating capacity is increased as the outside air temperature decreases, the heat absorption amount of the evaporator (14) increases as in the high outside air temperature at which the outside air temperature becomes high. In addition, unnecessary heating ability is not exhibited. Therefore, in an operation mode in which it is desirable to operate while exhibiting a high COP, the COP can be specifically improved by switching the operation mode to the first operation mode. Note that “constant” in the present invention does not only mean that the heating capacity is completely constant, but those that differ slightly due to a control error or the like are also included in the scope of the term “constant”.

  Further, in the invention according to claim 2, in the invention according to claim 1, in the first operation mode, the degree of increase in the heating capacity when the heating capacity is increased as the outside air temperature decreases can be changed. It is characterized by.

  According to this, in the first operation mode, since the degree of heating capacity when increasing the heating capacity can be changed, even when the heating capacity required for the heat pump cycle device fluctuates, the heating capacity is appropriately set. Can be secured.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the heat pump cycle device of the present invention is applied to a hot water storage type heat pump water heater 1 having a heating function for heating a house or the like. FIG. 1 is an overall configuration diagram of a hot water storage type heat pump water heater 1 according to the present embodiment.

  As shown in FIG. 1, the hot water storage type heat pump water heater 1 circulates a heat pump cycle 10 that circulates a refrigerant, a brine circulation circuit 20 that circulates a brine that is a fluid to be heated, and hot water in a hot water storage tank 31 that will be described later. The hot water circulation circuit 30 is roughly divided. In the present embodiment, water (antifreeze) to which a rust preventive component that lowers the freezing temperature, an antifreeze component, or the like is added is adopted as the brine.

  First, the heat pump cycle 10 is a vapor compression refrigeration cycle in which a compressor 11, a brine-refrigerant heat exchanger 12, an electric expansion valve 13, an evaporator 14 and the like are sequentially connected. This heat pump cycle 10 employs carbon dioxide as a refrigerant, and constitutes a supercritical refrigeration cycle in which the pressure of the high-pressure refrigerant discharged from the compressor 11 is equal to or higher than the critical pressure of the refrigerant.

  The compressor 11 sucks the refrigerant in the heat pump cycle 10 and compresses and discharges the refrigerant until the pressure becomes equal to or higher than the critical pressure. The electric compression drives the fixed displacement compressor 11a having a fixed discharge capacity by the electric motor 11b. Machine. Specifically, various compression mechanisms such as a scroll compression mechanism and a vane compression mechanism can be employed as the fixed capacity compressor 11a.

  The electric motor 11b is controlled in its operation (number of rotations) by a control signal output from the heat pump side control device 40 described later, and may adopt either an AC motor or a DC motor. And the refrigerant | coolant discharge capability of the compressor 11 is changed by this rotation speed control.

  The refrigerant discharge port of the compressor 11 is connected to the refrigerant passage 12 a inlet side of the brine-refrigerant heat exchanger 12. The brine-refrigerant heat exchanger 12 has a brine passage 12b through which the brine passes and a refrigerant passage 12a through which the high-temperature high-pressure refrigerant discharged from the compressor 11 passes, and exchanges heat between the brine and the refrigerant discharged from the compressor 11. It is a heat exchanger. Therefore, the brine-refrigerant heat exchanger 12 functions as a heating heat exchanger that heats the brine by the amount of heat discharged from the compressor 11.

  In addition, although the flow direction of the refrigerant | coolant in the refrigerant path 12a of the brine-refrigerant heat exchanger 12 of this embodiment and the flow direction of the brine in the brine path 12b are mutually the same directions, it is desirable to set it as the mutually opposing direction. If the flow direction of the refrigerant and the flow direction of the brine in the brine-refrigerant heat exchanger 12 are opposite to each other, the temperature difference between the refrigerant flowing through the refrigerant passage 12a and the brine flowing through the brine passage 12b is secured and heat is generated. Exchange efficiency can be improved.

  Further, in the heat pump cycle 10 of the present embodiment, a supercritical refrigeration cycle in which the pressure of the refrigerant discharged from the compressor 11 is equal to or higher than the critical pressure constitutes the refrigerant that passes through the refrigerant passage 12a of the brine-refrigerant heat exchanger 12. Radiates heat in a supercritical state without condensing.

  The inlet side of the electric expansion valve 13 is connected to the outlet side of the refrigerant passage 12 a of the brine-refrigerant heat exchanger 12. The electric expansion valve 13 is a pressure reducing unit that decompresses and expands the high-pressure refrigerant flowing out of the refrigerant passage 12a, and controls the pressure of the high-pressure side refrigerant from the refrigerant discharge port of the compressor 11 to the inlet side of the electric expansion valve 13. It is also a control means.

  More specifically, the electric expansion valve 13 includes a valve body portion 13a that can adjust the throttle opening degree and an electric actuator 13b that includes a servo motor that variably controls the throttle opening degree of the valve body portion 13a. Configured.

  An evaporator 14 is connected to the outlet side of the electric expansion valve 13. The evaporator 14 heat-exchanges the low-pressure refrigerant decompressed by the electric expansion valve 13 and the outside air (outdoor air) blown by the electric outdoor fan 14a, thereby evaporating the low-pressure refrigerant and exerting an endothermic effect. Functions as an endothermic heat exchanger.

  A refrigerant suction port of the compressor 11 is connected to the refrigerant outlet side of the evaporator 14. Therefore, when the heat pump side control device 40 operates the compressor 11, the refrigerant is in the order of the compressor 11 → the refrigerant passage 12 a of the brine-refrigerant heat exchanger 12 → the electric expansion valve 13 → the evaporator 14 → the compressor 11. Circulate.

  Next, the brine circulation circuit (closed circuit) 20 will be described. In the brine circulation circuit 20, the suction port of the circulation pump 21 is connected to the outlet side of the brine passage 12 b of the brine-refrigerant heat exchanger 12.

  The circulation pump 21 circulates the brine in the brine circulation circuit 20 by sucking and pumping the brine heated by the brine-refrigerant heat exchanger 12. The circulation pump 21 is an electric pump in which the rotation speed (brine flow rate) is controlled by a control signal output from the heating / hot water supply side control device 50 described later.

  On the outlet side of the circulation pump 21, a branching section 22 that branches the flow of brine pumped from the circulation pump 21 is provided. In the branch portion 22, a flow path switching valve 22a for switching the circulation path of the brine is disposed. The flow path switching valve 22a is configured by an electric three-way valve that switches the circulation path of the brine by a control signal output from the heating / hot water supply side control device 50, which will be described later, and heats the circulation path on the downstream side of the circulation pump 21. It functions as a flow path switching means for switching between the side path 20a and the hot water supply side path 20b.

  In the heating side path 20a, a heating device 23 for heating the house by dissipating the heat of the brine in the heating side path 20a is arranged. The heating device 23 of the present embodiment is a floor heating device that heats the floor by heating the floor in the house.

  On the outlet side of the heating device 23, a merging portion 25 is provided for merging the flow of brine flowing out of the heating side path 20a and the flow of brine flowing out of the hot water supply side path 20b. Further, the brine flow downstream side of the junction 25 is connected to the brine passage 12 b of the brine-refrigerant heat exchanger 12.

  Therefore, when the circulation path of the brine is switched to the heating-side path 20a, the brine heated by the brine-refrigerant heat exchanger 12 is the circulation pump 21 → the branch portion 22 (flow path switching valve 22a) → the heating device 23 → Circulation is performed in the order of the junction 25 → the brine path 12 b of the brine-refrigerant heat exchanger 12 → the circulation pump 21.

  On the other hand, the inlet side of the brine passage 24a of the brine-water heat exchanger 24 is connected to the hot water supply side passage 20b branched at the branching portion 22. The brine-water heat exchanger 24 has a brine passage 24a through which brine passes and a water passage 24b through which hot water in the hot water circulation circuit 30 passes, and is a heat exchanger that exchanges heat between the brine and hot water. . Therefore, the brine-water heat exchanger 24 functions as a heat exchanger that heats the hot water using the heat of the brine heated by the brine-refrigerant heat exchanger 12.

  In addition, the flow direction of the brine in the brine passage 24a of the brine-water heat exchanger 24 of the present embodiment and the flow direction of the hot water in the water passage 24b are opposite to each other. As described above, the brine flow direction and the hot water flow direction in the brine-water heat exchanger 24 are opposite to each other, so that the brine flowing through the brine passage 24a and the hot water flowing through the water passage 24b A temperature difference can be secured and heat exchange efficiency can be improved.

  Furthermore, the outlet side of the brine passage 24 a of the brine-water heat exchanger 24 is connected to the junction 25 described above.

  Therefore, when the brine circulation path is switched to the hot water supply side path 20b, the brine heated by the brine-refrigerant heat exchanger 12 is the circulation pump 21 → branch 22 (flow path switching valve 22a) → brine-hydrothermal. It circulates in the order of the brine passage 24a of the exchanger 24 → the merging portion 25 → the brine passage 12b of the brine-refrigerant heat exchanger 12 → the circulation pump 21.

  Next, the hot water supply circuit 30 will be described. A hot water storage tank 31 is disposed in the hot water supply circuit 30. The hot water storage tank 31 has a heat insulating structure and is a hot water tank for keeping hot hot water for a long time, and is formed of a metal (for example, stainless steel) having excellent corrosion resistance.

  Hot water stored in the hot water storage tank 31 is discharged from a hot water outlet provided in the upper part of the hot water storage tank 31 and mixed with cold water from a water supply at a temperature control valve (not shown) to adjust the temperature. Hot water is supplied. In addition, tap water is supplied from a water supply port provided in the lower part of the hot water storage tank 31.

  Further, the hot water supply circuit 20 is provided with a water pump 32 that circulates the hot water supply circuit 20 by sucking and pumping hot water in the hot water storage tank 31. The water pump 32 is an electric pump whose operation is controlled by a control signal output from a heating / hot water supply side control device 50 described later.

  The outlet side of the water pump 32 is connected to the water passage 24 b of the brine-water heat exchanger 24. The outlet side of the water passage 24b of the brine-water heat exchanger 24 is connected to the hot water storage tank 31, and the water heated by the brine-water heat exchanger 24 is returned to the hot water storage tank 31 to be stored.

  Therefore, when the heating and hot water supply side control device 50 operates the water pump 32, the hot water is circulated in the order of the water pump 32 → the water passage 24 b of the brine-water heat exchanger 24 → the hot water storage tank 31 → the water pump 32.

  Next, an outline of the electric control unit of the present embodiment will be described. The heat pump side control device (heat pump ECU) 40 and the heating hot water supply side control device (heating hot water supply ECU) 50 are each configured by a well-known microcomputer including a CPU, ROM, RAM, etc. and its peripheral circuits.

  An electric motor 11b of the compressor 11, an electric outdoor fan 14a, an electric actuator 13b of the electric expansion valve 13, and the like are connected to the output side of the heat pump side control device 40, and the operation of these devices is controlled. Further, the circulation pump 21 of the brine circulation circuit 20, the flow path switching valve 22a, the water pump 32 of the hot water supply circuit 30 and the like are connected to the output side of the heating and hot water supply side control device 50 to control the operation of these devices. .

  The heat pump-side control device 40 is configured such that the control means for controlling the actuators described above is integrally formed. In the present embodiment, the operation (refrigerant discharge capacity) of the electric motor 11b of the compressor 11 is mainly used. A configuration (hardware and software) for controlling the operation (hardware and software) and a configuration (hardware and software) for controlling the operation (throttle opening) of the electric expansion valve 13 are referred to as heating capacity adjusting means. Here, the heating capacity is determined by the temperature (pressure) of the refrigerant passing through the refrigerant passage 12a of the brine-refrigerant heat exchanger 12 and the flow rate of the refrigerant.

  Further, on the input side of the heat pump side control device 40, there are an outside air temperature sensor 41 for detecting the outside air temperature outside the house, and a first brine temperature sensor for detecting the brine temperature on the inlet side of the brine passage 12b of the brine-refrigerant heat exchanger 12. 42, a second brine temperature sensor 43 for detecting a brine temperature on the outlet side of the brine passage 12b of the brine-refrigerant heat exchanger 12, and a hot water supply water for detecting the temperature of hot water flowing out of the water passage 24b of the brine-water heat exchanger 24 A temperature sensor 44 and the like are connected, and detection signals from these sensor groups are input to the control device 40.

  In this embodiment, as the outside air temperature sensor 41, a thermistor that specifically detects the outside air temperature upstream of the air flow of the evaporator 14 is employed. Of course, other types of outside air temperature detection means (for example, a thermocouple) may be employed.

  Furthermore, an operation panel 45 is connected to the input side of the heat pump side control device 40, and an operation signal for operating / stopping the hot water storage type heat pump water heater 1, an operation mode switching signal, a target heating temperature setting signal for the heating device 23, A target hot water supply temperature setting signal or the like of hot water is input to the heat pump side control device 40. Accordingly, the operation panel 45 constitutes mode switching means for switching the operation of the hot water storage type heat pump water heater 1 between the heating operation mode and the hot water supply operation mode.

  Here, the heat pump side control device 40 and the heating / hot water supply side control device 50 are electrically connected to each other and configured to be communicable. Thereby, based on the detection signal and operation signal which were input into one control apparatus, the other control apparatus can also control operation | movement of the above-mentioned various actuators. Therefore, the heat pump side control device 40 and the heating / hot water supply side control device 50 may be integrally configured as one control device.

  Next, the operation of the hot water storage type heat pump water heater 1 of the present embodiment in the above configuration will be described with reference to FIG. FIG. 2 is a flowchart showing a control process executed by the heat pump side control device 40. This control process starts when an operation signal from the operation panel 45 is input to the heat pump side control device 40 in a state where power is supplied to the hot water storage type heat pump water heater 1 from the outside.

  First, in step S1, flags, timers, etc. are initialized. Then, in the next step S2, the operation signal of the operation panel 45, the detection signal detected by the sensor groups 41 to 44, etc. are read.

  The hot water storage type heat pump water heater 1 of the present embodiment is switched between the hot water supply operation mode and the heating operation mode based on the operation mode switching signal of the operation panel 45. Specifically, when the heating operation mode is selected on the operation panel 45, the heating hot water supply side control device 50 operates the flow path switching valve 22a so as to switch the circulation path of the brine to the heating side path 20a, When the hot water supply operation is selected, the flow path switching valve 22a is operated so as to switch the brine circulation path to the hot water supply side path 20b.

  Next, the process proceeds to step S3, and control states of various actuators, that is, control signals output to the various actuators are determined based on the operation signal and detection signal read in step S2.

  Specifically, control signals to be output to the electric motor 11b of the compressor 11, the electric actuator 13b of the electric expansion valve 13, the circulation pump 21 of the brine circulation circuit 20, the water pump 32 of the hot water circulation circuit 30, and the like are determined. The

  For example, the signal output to the circulation pump 21 of the brine circulation circuit 20 indicates that the brine temperature detected by the second brine temperature sensor 43 is the value of the heating device 23 when the operation of the hot water storage heat pump water heater 1 is the heating operation. It is determined to approach the target heating temperature.

  On the other hand, when the operation of the hot water storage heat pump water heater 1 is a hot water supply operation, the signal output to the water pump 32 of the hot water circulation circuit 30 indicates that the hot water temperature detected by the hot water temperature sensor 44 becomes the target hot water temperature. Determined to approach. The target hot water supply temperature is higher than the above-described target heating temperature.

  Here, as in the present embodiment, when performing operations with different purposes such as the heating operation mode and the hot water supply operation mode, the heating capacity required for the heat pump cycle 10 may differ between the heating operation mode and the hot water supply operation mode. .

  For example, in the hot water supply operation mode, it is necessary to raise the hot water supply temperature to a high target hot water supply temperature, so that the heating capacity of the heat pump cycle 10 is maintained substantially constant even if the coefficient of performance (COP) of the heat pump cycle decreases. There must be.

  On the other hand, in order to raise the brine supplied to the heating device 23 to the target heating temperature that is a low intermediate temperature with respect to the hot water supply, for example, in the heating operation mode, the heating capacity is appropriately controlled while exhibiting a high COP. It is desirable to operate the hot water storage type heat pump water heater 1.

  Therefore, in the heating operation mode of the present embodiment, in order to appropriately control the heating capacity while exhibiting a high COP, each actuator 11b, 13b of the heat pump cycle 10 is increased so as to increase the heating capacity as the outside air temperature decreases. Control signals are determined.

  On the other hand, in the hot water supply operation mode, in order to raise the hot water to the target hot water temperature set to a high temperature, the control signals of the actuators 11b and 13b are set so that the heating capacity becomes substantially constant regardless of the change in the outside air temperature. It is determined.

  That is, in the present embodiment, the operation in the heating operation mode (first operation mode) in which the heating capacity is increased as the outside air temperature decreases, and the hot water supply operation mode in which the heating capacity is maintained constant regardless of the change in the outside temperature. The operation in the (second operation mode) can be switched.

  Here, the determination process of the control signal of each actuator 11b, 13b of the heat pump cycle 10 will be specifically described based on FIG. FIG. 3 is a flowchart showing a control signal determination process of each actuator executed by the heat pump side control device.

  As shown in FIG. 3, first, in step S31, it is determined whether or not the operation mode of the hot water storage type heat pump water heater 1 is the heating operation mode. This determination process is performed based on a switching signal output from the operation panel 45.

  When it determines with heating operation mode in step S31, the heating capability required at the time of heating operation mode is determined in step S32. Specifically, the heating capacity in the heating operation mode is determined so as to increase the heating capacity as the outside temperature detected by the outside temperature sensor 41 decreases.

  More specifically, as shown to Fig.4 (a), it determines so that a heating capability may be increased in proportion to the fall of outside temperature. That is, the degree of increase in the heating capacity when the heating capacity is increased as the outside air temperature decreases is set to a certain degree of increase (the slope of FIG. 4A is constant). FIG. 4A is a control characteristic diagram showing the relationship between the outside air temperature and the heating capacity in the heating operation mode.

  In step S33, control signals for the actuators 11b and 13b of the heat pump cycle 10 are determined so as to achieve the heating capacity determined in step S32. For example, the control signals to the electric motor 11b of the compressor 11 and the electric actuator 13b of the expansion valve 13 are referred to the control map stored in advance in the heat pump side control device 40 based on the heating capacity determined in step S32. And decide.

  On the other hand, when it determines with hot water supply operation mode by step S31, the heating capability required at the time of hot water supply operation mode is determined by step S34. Specifically, as shown in FIG. 4B, the heating capacity in the hot water supply operation mode is determined so as to maintain the heating capacity substantially constant regardless of the change in the outside air temperature. FIG. 4B is a control characteristic diagram showing the relationship between the outside air temperature and the heating capacity in the hot water supply operation mode.

  In step S33, control signals for the actuators 11b and 13b of the heat pump cycle 10 are determined so as to achieve the heating capacity determined in step S34. For example, the control signals to the electric motor 11b of the compressor 11 and the electric actuator 13b of the expansion valve 13 refer to the control map stored in advance in the heat pump side control device 40 based on the heating capacity determined in step S34. And decide.

  Returning to FIG. 2, various actuators 11 b, 13 b, 21, 22 are transmitted from the heat pump side control device 40 and the heating / hot water supply side control device 50 in step S <b> 4 so that the control state of each actuator determined in step S <b> 3 can be obtained. , 32, a control signal is output.

  Thereby, the high-temperature and high-pressure refrigerant discharged from the compressor 11 flows into the refrigerant passage 12a of the brine-refrigerant heat exchanger 12, and heats the brine flowing through the brine passage 12b of the brine-refrigerant heat exchanger 12. .

  In the heating operation mode, the brine heated by the brine-refrigerant heat exchanger 12 flows into the heating device 23 through the heating side path 20a and raises the temperature of the heating target in the house. On the other hand, in the hot water supply operation mode, the hot water flows into the brine passage 24a of the brine-water heat exchanger 24 through the hot water supply side passage 20b to heat the hot water in the water passage 24b of the brine-water heat exchanger 24. The hot water heated by the heat of the brine is stored on the upper side of the hot water storage tank 31.

  In the next step S5, when the stop signal of the hot water storage type heat pump water heater 1 from the operation panel 45 is input to the control device 40, the operation of various actuators is stopped and the hot water storage type heat pump water heater 1 is operated. Stop. On the other hand, when the stop signal of the hot water storage type heat pump water heater 1 from the operation panel 45 is not input to the control device 40, after waiting for a predetermined control period, the process returns to step S2.

  According to the operation of the hot water storage type heat pump water heater 1 described above, in the heating operation mode, the heating capacity is increased as the outside air temperature decreases, so that the evaporator 14 has a high outdoor temperature when the outside air temperature becomes high. When the endothermic amount increases, unnecessary heating ability is not exhibited. Therefore, COP can be improved in the heating operation mode in which it is desirable to operate while exhibiting high COP. Further, in the heating operation mode, the heating capacity required for the heat pump cycle 10 can be appropriately ensured at a low outside air temperature at which the outside air temperature is low.

  On the other hand, in the hot water supply operation mode, the heating capability is maintained constant regardless of the change in the outside air temperature. Accordingly, heating of hot water supply can be prioritized over improvement of COP, and the required heating capacity can be sufficiently ensured.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. In the present embodiment, only the parts different from the first embodiment will be described. FIG. 5 is a control characteristic diagram showing the relationship between the outside air temperature and the heating capacity of the heat pump cycle 10 in the heating operation mode in the present embodiment.

  In the present embodiment, when the target heating temperature of the heating device 23 is changed and the heat load of the heat pump cycle 10 fluctuates in the heating operation mode, the heating capacity required for the heat pump cycle 10 is appropriately secured. Yes.

  That is, in the present embodiment, in the heating operation mode, the degree of increase in heating capacity (heating capacity) according to the change in the outside air temperature when the target heating temperature of the heating device 23 is set to a high temperature and when it is set to a low temperature. The degree of increase) can be changed.

  In other words, the heat capacity of the heat pump cycle 10 can be changed between the case where the heat load becomes a high heat load and the case where the heat load becomes a low heat load. Yes.

  For example, as shown in FIG. 5, when the heat load of the heat pump cycle 10 becomes a high heat load, the required heating capacity increases, so the degree of increase in heating capacity accompanying a decrease in outside air temperature is increased, When the heat load is a low heat load, the required heating capacity is reduced, so that the degree of increase in the heating capacity accompanying a decrease in the outside air temperature is reduced.

  In this way, in the heating operation mode, the degree of heating capacity when increasing the heating capacity can be changed, so that even when the heating capacity required for the hot water storage type heat pump water heater 1 fluctuates, the heating capacity is appropriately set. Can be secured.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows.

  (1) In the hot water storage heat pump water heater 1 of each of the above-described embodiments, in the heating operation mode, the heating capacity is increased as the outside air temperature decreases, and the heating capacity is constant regardless of the change in the outside air temperature in the hot water operation mode. However, the present invention is not limited to this, and various modifications are possible. For example, in the hot water supply operation mode, when performing different operations such as a first hot water supply operation mode in which hot water is raised to a high temperature, a second hot water supply operation mode in which the hot water is raised to an intermediate temperature, and the like, Accordingly, an operation for increasing the heating capacity may be performed.

  (2) In each of the above-described embodiments, in the above-described embodiments, the present invention is applied to the hot water storage heat pump water heater 1 that switches between the heating operation and the hot water supply operation, but the application of the present invention is not limited to this. . In this invention, if it is the heat pump cycle apparatus which has the operation mode from which the objective differs and the heating capability required for the heat pump cycle 10 in each operation mode differs, it can apply to various apparatuses.

  In each of the above-described embodiments, the example in which the heating device 23 is applied to the floor heating device has been described. However, the heating device 23 may be applied to another device (for example, an air conditioner).

  (3) In the heat pump cycle 10 of each of the above-described embodiments, the supercritical refrigeration cycle is configured using carbon dioxide as a refrigerant. The subcritical refrigeration cycle may be configured using a refrigerant that does not exceed the critical pressure.

  (4) In each embodiment described above, an example in which an electric compressor is adopted as the compressor 11 has been described, but the compressor 11 is not limited to this. For example, an engine-driven variable capacity compressor may be employed.

  (5) The heat pump cycle 10 of each of the above embodiments may be provided with an accumulator as a gas-liquid separation unit that separates the gas-liquid of the refrigerant flowing out of the evaporator 14 and stores excess refrigerant.

  (6) In each of the above-described embodiments, an example in which water added with an antifreeze component or the like is used as a brine has been described. However, the present invention is not limited thereto, and for example, the brine may be fresh water.

  (7) In each of the above-described embodiments, the flow path switching valve 22a is disposed at the branching section 22. However, the present invention is not limited thereto, and may be disposed at the merging section 25.

1 is an overall configuration diagram of a hot water storage type heat pump water heater according to a first embodiment. It is a flowchart which shows the control processing of the control apparatus which concerns on 1st Embodiment. It is a flowchart which shows the control processing of the control apparatus which concerns on 1st Embodiment. It is a control characteristic figure which shows the relationship between the external temperature and heating capability in each operation mode. It is a control characteristic figure which shows the principal part of the control apparatus which concerns on 2nd Embodiment.

Explanation of symbols

11 compressor 12 brine-refrigerant heat exchanger (heat exchanger for heating)
13 Electric expansion valve (pressure reduction means)
14 Evaporator

Claims (1)

Compressor (11) for sucking and compressing refrigerant, heating heat exchanger (12) for heating fluid to be heated by high-pressure refrigerant discharged from compressor (11), heating heat exchanger (12) A heat pump (10) having a depressurization means (13) for depressurizing the high-pressure refrigerant that has passed through, an evaporator (14) for evaporating the low-pressure refrigerant depressurized by the depressurization means (13),
Heating capacity adjusting means (40) for adjusting the heating capacity for heating the fluid to be heated;
A circulation circuit (20) for circulating the fluid to be heated;
A hot water circulation circuit (30) for circulating hot water in the hot water storage tank;
Mode switching means (45) for switching the operation mode;
With
The mode switching means (45) switches between a first operation mode in which the heating capacity is increased as the outside air temperature decreases and a second operation mode in which the heating capacity is maintained constant regardless of a change in the outside air temperature. In the first operation mode, the degree of increase in the heating capacity when the heating capacity is increased as the outside air temperature decreases is set so that the heat load of the heat pump cycle (10) becomes a high heat load. It is configured to be changeable depending on the case and low heat load,
The circulation circuit includes
A heating device (23) for radiating and heating the heat of the fluid to be heated;
A heat exchanger (24) for exchanging heat between the fluid to be heated and the hot water,
The heating target fluid circulation path includes a heating side path (20a) for circulating the heating target fluid in the heating device (23), and a hot water supply side path (circulation) for circulating the heating target fluid in the heat exchanger (24). And a flow path switching means (22a) for switching to 20b),
The flow path switching means (22a) switches the circulation path of the heating target fluid to the heating side path (20a) during the first operation mode, and switches the circulation path of the heating target fluid to the hot water supply during the second operation mode. It is comprised so that it may switch to a side path | route (20b), The heat pump cycle apparatus characterized by the above-mentioned.

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