JP6994396B2 - Heat supply system - Google Patents

Description

The techniques disclosed herein relate to heat supply systems.

Patent Document 1 describes a heat pump that heats a heat medium, a tank that stores the heat medium heated by the heat pump, a supply path that supplies the heat medium in the tank to a heat utilization location, and heat generated by burning fuel. A heat supply system comprising a combustor for heating a heat medium using a heat medium is disclosed. This makes it possible to operate the combustor to supplement the heat when the heat in the tank stored by using the heat pump is insufficient.

Japanese Unexamined Patent Publication No. 2011-153779

This type of heat supply system may be configured by combining two units, a first unit that includes a heat pump and a second unit that includes a tank, a combustor, and a supply path. In that case, the first unit and the second unit each have a power supply system for supplying electric power from the power source individually. However, if the power supply system of the first unit and the power supply system of the second unit are connected to a common outlet (for example, an outdoor outlet) to supply power, when the first unit and the second unit operate at the same time, the first unit and the second unit operate at the same time. The rated current of the outlet may be exceeded.

The present specification provides a technique capable of appropriately suppressing the occurrence of a situation in which the current flowing through the heat supply system exceeds the rated current of the outlet.

This specification discloses a heat supply system installed in a building having an outlet powered by a power source and operating connected to the outlet. The heat supply system includes a first unit, a second unit, and a control device. The first unit includes a compressor, a condenser, a decompression mechanism, a heat pump provided with an evaporator to heat a heat medium, and a first power supply system connected to the outlet. The second unit has at least one of a tank for storing the heat medium and a combustor for heating the heat medium, and a second power supply system connected to the outlet. In the control device, in a situation where the rotation speed of the compressor should be increased during the operation of the heat pump, the unit working current value, which is the working current value of the first unit, is the first when the rotation speed is increased. When it is predicted that the rotation speed will be equal to or higher than the threshold value, the maintenance control for maintaining the rotation speed is executed. The first threshold value is a value smaller than the first upper limit value which is the upper limit value of the system working current value which is the total working current value of the first unit and the second unit.

According to this configuration, the control device has a unit operating current value when the rotation speed is increased in a situation where the rotation speed of the compressor of the heat pump should be increased, for example, in a situation where the heating capacity of the heat pump should be increased. When it is predicted that the number of revolutions will exceed one threshold, maintenance control for maintaining the rotation speed without increasing it is executed. Generally, as the number of revolutions of a compressor increases, the current value of the heat pump increases accordingly. Therefore, when the control device executes the maintenance control, it is possible to suppress an increase in the current value used by the unit. As a result, it is possible to prevent the system operating current value from exceeding the first upper limit value. That is, according to the above configuration, by appropriately setting the first threshold value and the first upper limit value, it is possible to appropriately suppress the occurrence of a situation in which the current flowing through the heat supply system exceeds the rated current of the outlet. ..

The control device may further perform a reduction control for reducing the rotation speed when the current value used by the unit during the operation of the heat pump is equal to or higher than the first threshold value.

According to this configuration, the control device reduces the rotation speed of the compressor of the heat pump when the current value used by the unit is equal to or higher than the first threshold value. By reducing the rotation speed of the compressor, the current value used by the heat pump can be reduced. As a result, the unit working current value can be made lower than the first threshold value, and the system working current value can be made lower than the first upper limit value accordingly. That is, according to the above configuration, even when the unit operating current value becomes equal to or higher than the first threshold value, it is possible to appropriately suppress the occurrence of a situation in which the current flowing through the heat supply system exceeds the rated current of the outlet. ..

The control device may further execute stop control for stopping the compressor when the current value used by the unit during the operation of the heat pump is equal to or higher than the second threshold value. The second threshold value may be a value smaller than the first upper limit value and a value larger than the first threshold value.

According to this configuration, the control device stops the compressor of the heat pump when the current value used by the unit is equal to or higher than the second threshold value. By stopping the compressor, it is possible to suppress the occurrence of a situation in which the system operating current value exceeds the first upper limit value. That is, according to the above configuration, by appropriately setting the second threshold value and the first upper limit value, the current flowing through the heat supply system even when the unit used current value becomes equal to or higher than the second threshold value. However, it is possible to appropriately suppress the occurrence of a situation in which the rated current of the outlet is exceeded.

The control device uses information on at least one of the temperature of each part of the first unit and the operating state of the elemental equipment of the first unit to rotate the rotation speed in a situation where the rotation speed should be increased. The unit operating current value when the number is increased may be predicted.

The above-mentioned "temperature of each part of the first unit" is, for example, the temperature of the refrigerant introduced into the compressor of the heat pump, the temperature of the refrigerant derived from the compressor, the temperature of the refrigerant introduced into the evaporator, and the condenser. It may include the temperature of the passing refrigerant, the outside temperature, the temperature of the heat medium before being heated by the heat pump, the temperature of the heat medium after being heated by the heat pump, and the like. Further, the above-mentioned "elemental equipment of the first unit" may include, for example, a compressor of a heat pump, an expansion valve of a heat pump, a fan of a heat pump, a circulation pump for moving a heat medium for heating by the heat pump, and the like. ..

According to the above configuration, the control device can appropriately predict the unit operating current value when the rotation speed is increased in the situation where the rotation speed should be increased. Based on a properly predicted unit operating current value, it is possible to suppress the occurrence of a situation in which the current flowing through the heat supply system exceeds the rated current of the outlet.

The building may have one or more branch circuits connected to the power source to branch the power supplied from the power source. The outlet may be connected to a specific branch circuit among the one or more branch circuits, and may receive power from the power source via the specific branch circuit. Further, the control device is outside the system excluding the first unit and the second unit from the upper limit value of all devices, which is the upper limit value of the total current value of all devices supplied with power via the specific branch circuit. The second upper limit value, which is a value excluding the total current value of the equipment, may be calculated. Further, when the calculated second upper limit value is equal to or less than the first upper limit value, the control device operates the compressor so that the system working current value is lower than the second upper limit value. When the calculated second upper limit value is larger than the first upper limit value, the compressor may be operated so that the system working current value is lower than the first upper limit value.

According to this configuration, the control device suppresses the system working current value to be equal to or higher than the second upper limit value, which is the value obtained by subtracting the total working current value of the devices outside the system from the upper limit value of all devices, while suppressing the first unit. And the second unit can be operated. As a result, according to the above configuration, by appropriately setting the upper limit value of all devices, the current value used by all devices exceeds the upper limit value of all devices, and the current value used by the system becomes the first upper limit value or. It is possible to control the current value of all the devices while suppressing the value from being equal to or higher than the second upper limit. Therefore, it is possible to operate the heat supply system according to the operating state of the equipment outside the system and appropriately suppress the occurrence of a situation where the total current used of all the equipment flowing in the specific branch circuit exceeds the rated current of the specific branch circuit. ..

The figure which shows the outline of the building where the hot water supply system 2 which concerns on an Example is installed schematically. The figure which shows typically the structure of the hot water supply system 2 which concerns on Example. A flowchart showing the current value control process of the first embodiment. The flowchart which shows the current value control processing of 2nd Example. The flowchart which shows the current value control processing of 3rd Embodiment. The flowchart which shows the current value control processing of 4th Embodiment. The flowchart which shows the predicted current value difference calculation process of 4th Example. The flowchart which shows the temperature correction process of 4th Example. The flowchart which shows the current value control processing of 5th Embodiment. The flowchart which shows the threshold value correction processing of 5th Embodiment. The flowchart which shows the current value control processing of 6th Embodiment.

(First Example)
As shown in FIG. 1, the hot water supply system 2 according to an embodiment of the heat supply system is installed in, for example, a building 500 such as a house, and hot water (heat medium) is placed in a hot water utilization location (heat utilization location example) of the building 500. Example) is a system used to supply. The hot water supply system 2 includes a heat pump unit 4, a tank unit 6, and a combustor unit 8. As shown in FIG. 1, the heat pump unit 4, the tank unit 6, and the combustor unit 8 are all provided outside the building 500 (that is, outdoors).

The building 500 includes a distribution board 11, an outdoor outlet 16, and an indoor outlet 18.

The distribution board 11 is connected to the commercial power supply 10, and supplies electric power from the commercial power supply 10 to each device inside and outside the building 500. The distribution board 11 includes one main breaker 12 and a plurality of branch breakers 14a, 14b, 14c. The main breaker 12 is connected to the commercial power source 10. Each of the plurality of branch breakers 14a to 14c is connected to the main breaker 12. In the example of FIG. 1, the branch breaker 14a is connected to the outdoor outlet 16 via the wiring 24 and the indoor outlet 18 is connected to the branch breaker 14a via the wiring 26. Further, outlets and terminal devices (not shown) are connected to the branch breakers 14b and 14c via wirings 27 and 28, respectively.

The branch circuit branched by the branch breaker 14a is attached to the terminal equipment (terminal equipment 19, heat pump unit 4, tank unit 6, combustor unit 8 in FIG. 1) of outdoor and partial indoor (for example, washroom). It is a circuit for supplying electric power. Further, the branch circuit branched by the branch breaker 14b is a circuit for supplying electric power to a terminal device (for example, an air conditioner, a television, etc.) in another part of the room (for example, a living room), and is branched by the branch breaker 14c. The branch circuit is a circuit for supplying electric power to a terminal device (for example, a microwave oven, an electric pot, etc.) in yet another part of the room (for example, a kitchen, etc.).

The main breaker 12 cuts off the current flowing from the commercial power source 10 to the branch breakers 14a to 14c when the current exceeds a predetermined threshold value (for example, 60A). Further, the branch breaker 14a cuts off the current when the current flowing through the wirings 24 and 26 exceeds a predetermined threshold value (for example, 20A). Similarly, the branch breakers 14b and 14c also cut off the current when the current flowing through the wirings 27 and 28 exceeds a predetermined threshold value (for example, 20A), respectively.

The indoor outlet 18 is an outlet provided in a part of the building 500 (for example, a washroom or the like). A terminal device 19 used indoors is connected to the indoor outlet 18. The terminal device 19 is a device not included in the hot water supply system 2, such as a dryer. FIG. 1 shows a state in which only one terminal device 19 is connected to the indoor outlet 18, but in reality, a plurality of devices may be connected to the indoor outlet 18.

The outdoor outlet 16 is an outlet provided outside the building 500. Wiring 20, which is a part of the heat pump unit 4, is connected to the outdoor outlet 16. Further, the wiring 22 which is a part of the tank unit 6 is also connected to the outdoor outlet 16. Further, the tank unit 6 and the combustor unit 8 are connected to each other via the wiring 23. As a result, electric power is supplied from the outdoor outlet 16 to each element device of the heat pump unit 4 via the wiring 20. Further, electric power is supplied from the outdoor outlet 16 to each elemental device of the tank unit 6 via the wiring 22, and electric power is also supplied to each elemental device of the combustor unit 8 via the tank unit 6 and the wiring 23. Will be done. FIG. 1 shows a state in which the tank unit 6 is connected to the outdoor outlet 16 via the wiring 22, but in another example, the combustor unit 8 is connected to the outdoor outlet 16 via the wiring 22. It may be connected.

(Structure of heat pump unit 4)
As shown in FIG. 2, the heat pump unit 4 includes a heat pump 40, a tank water circulation path 70, a circulation pump 72, and a heat pump control unit 80.

The heat pump 40 is a heat source that absorbs heat from the outside air and heats the water in the tank water circulation path 70. The heat pump 40 includes a refrigerant circulation path 41 that circulates a refrigerant (alternative freon, for example, R410A, etc.), an evaporator 42 that exchanges heat between the outside air and the refrigerant, a fan 43 that blows outside air to the evaporator 42, and the fan 43. The compressor 44 that compresses the refrigerant to make it high temperature and high pressure, the condenser 45 that exchanges heat between the water in the tank water circulation path 70 and the high temperature and high pressure refrigerant, and the refrigerant after heat exchange is depressurized. It is provided with an expansion valve 46 for lowering the temperature and pressure.

The upstream end of the tank water circulation path 70 is connected to the lower part of the tank 100 in the tank unit 6, and the downstream end is connected to the upper part of the tank 100. A circulation pump 72 is interposed in the tank water circulation passage 70. The circulation pump 72 sends out the water in the tank water circulation path 70 from the upstream side to the downstream side. Further, the tank water circulation path 70 passes through the condenser 45 of the heat pump 40. Therefore, when the heat pump 40 is operated (that is, when the fan 43 and the compressor 44 are operated), the water in the tank water circulation path 70 is heated by the condenser 45 of the heat pump 40. Therefore, when the circulation pump 72 and the heat pump 40 are operated, the water in the lower part of the tank 100 is heated by the condenser 45, and the heated water is returned to the upper part of the tank 100. That is, the tank water circulation channel 70 is a water channel for storing heat in the tank 100.

Further, the heat pump unit 4 is provided with eight thermistors 52 to 66. The thermistor 52 is provided on the upstream side of the compressor 44 of the refrigerant circulation path 41, and detects the temperature (that is, the compressor suction temperature) TH1 of the refrigerant sucked into the compressor 44. The thermistor 54 is provided on the downstream side of the compressor 44 of the refrigerant circulation path 41, and detects the temperature (that is, the compressor discharge temperature) TH2 of the refrigerant discharged from the compressor 44. The thermistor 56 is provided on the upstream side of the expansion valve 46 of the refrigerant circulation path 41, and detects the temperature (that is, the expansion valve inflow temperature) TH3 of the refrigerant flowing into the expansion valve 46. The thermistor 58 is provided on the upstream side of the evaporator 42 of the refrigerant circulation path 41, and detects the temperature (that is, the evaporation temperature) TH4 of the refrigerant flowing into the evaporator 42. The thermistor 60 is attached to the condenser 45 and detects the temperature (condensation temperature) TH5 of the refrigerant in the condenser 45. The thermistor 62 is attached to a housing (not shown) of the heat pump unit 4 and detects the outside air temperature TH6. The thermistor 64 is provided on the upstream side of the condenser 45 of the tank water circulation path 70, is led out from the lower part of the tank 100, and detects the temperature (that is, the water entry temperature) TH7 of the water before passing through the condenser 45. The thermistor 66 is provided on the downstream side of the condenser 45 of the tank water circulation path 70, and detects the temperature of water (that is, the hot water temperature) TH8 after passing through the condenser 45.

The heat pump control unit 80 is electrically connected to each element device of the heat pump unit 4 and controls the operation of each element device. Further, the heat pump control unit 80 is provided so as to be able to communicate with each other with the tank control unit 180 of the tank unit 6 and the combustor control unit 280 of the combustor unit 8. When operating the heat pump 40, the heat pump control unit 80 executes a normal control process (not shown) and a current value control process (see FIG. 3), which will be described later. The details of the normal control and the current value control process will be described later.

(Structure of tank unit 6)
The tank unit 6 includes a tank 100, a tap water introduction path 110, a supply path 130, and a tank control unit 180.

The tank 100 stores hot water heated by the heat pump 40. The tank 100 is a closed type, and the outside is covered with a heat insulating material. Water is stored in the tank 100 until it is full. In this embodiment, the capacity of the tank 100 is 100 L. Thermistors 102, 104, 106, and 108 are attached to the tank 100 at predetermined intervals in the height direction of the tank 100. Each thermistor 102, 104, 106, 108 detects the temperature of water at its mounting position. For example, each thermistor 102, 104, 106, 108 detects the temperature of water at positions 6L, 12L, 30L, 50L from the top of the tank 100, respectively.

The upstream end of the tap water introduction path 110 is connected to the tap water supply source 112. The downstream side of the tap water introduction path 110 is branched into a first introduction path 110a and a second introduction path 110b. The downstream end of the first introduction path 110a is connected to the lower part of the tank 100. The downstream end of the second introduction path 110b is connected in the middle of the supply path 130 described later. A mixing valve 140 is provided at a connection portion between the downstream end of the second introduction path 110b and the supply path 130. The mixing valve 140 adjusts the amount of hot water flowing in the supply path 130 to be mixed with the water in the second introduction path 110b.

The upstream end of the supply path 130 is connected to the upper part of the tank 100. As described above, the second introduction passage 110b of the tap water introduction passage 110 is connected in the middle of the supply passage 130, and the mixing valve 140 is provided at the connection portion. A combustor 200 (described later) of a combustor unit 8 is interposed in a supply path 130 on the downstream side of the connection portion with the second introduction path 110b. The downstream end of the supply path 130 is connected to a hot water utilization point (for example, a kitchen, a bathtub, etc.).

The tank control unit 180 is electrically connected to each element device of the tank unit 6 and controls the operation of each element device. Further, the tank control unit 180 is provided so as to be able to communicate with each other with the heat pump control unit 80 of the heat pump unit 4 and the combustor control unit 280 of the combustor unit 8.

(Combustor unit 8 configuration)
The combustor unit 8 includes a combustor 200 and a combustor control unit 280.

The combustor 200 is an auxiliary heat source machine that heats hot water passing through the above-mentioned supply path 130 by the heat of burning fuel (for example, fuel gas). Further, a thermistor 210 is interposed in the supply path 130 on the downstream side of the combustor 200. The thermistor 210 detects the temperature of the hot water supplied to the hot water utilization point. The combustor 200 heats the water in the supply path 130 so that the temperature of the hot water detected by the thermistor 210 matches the hot water supply set temperature. As described above, the downstream end of the supply path 130 is connected to the hot water utilization point.

The combustor control unit 280 is electrically connected to each element device of the combustor unit 8 and controls the operation of each element device. As described above, the combustor control unit 280 can communicate with the heat pump control unit 80 and the tank control unit 180.

Hereinafter, the heat pump control unit 80, the tank control unit 180, and the combustor control unit 280 may be collectively referred to simply as a “control unit”.

Next, the operation of the hot water supply system 2 of this embodiment will be described. The hot water supply system 2 can execute the heat storage operation and the hot water supply operation. Hereinafter, each operation will be described.

(Heat storage operation)
The heat storage operation is an operation in which the water in the tank 100 is heated by the heat pump 40. When the control unit instructs the execution of the heat storage operation, the heat pump 40 starts operating (that is, the compressor 44 and the fan 43 are operated), and the circulation pump 72 rotates. When the circulation pump 72 rotates, the water in the tank 100 circulates in the tank water circulation path 70. That is, the water existing in the lower part of the tank 100 is introduced into the tank water circulation path 70, and when the introduced water passes through the condenser 45 in the heat pump 40, it is heated by the heat of the refrigerant and the heated water is discharged. It is returned to the top of the tank 100. As a result, hot water is stored in the tank 100. A layer of hot water is formed in the upper part of the tank 100, and a layer of cold water is formed in the lower part.

(Hot water supply operation)
The hot water supply operation is an operation of supplying the water in the tank 100 to the hot water utilization point. The hot water supply operation can also be executed during the above heat storage operation. When the hot water tap at the hot water utilization point is opened, tap water flows from the tap water introduction path 110 (first introduction path 110a) to the lower part of the tank 100 due to the water pressure from the tap water supply source 112. At the same time, the hot water in the upper part of the tank 100 is supplied to the hot water utilization point via the supply path 130.

When the temperature of the water supplied from the tank 100 to the supply path 130 (that is, the measured temperature of the thermistor 102) is higher than the hot water supply set temperature, the control unit opens the mixing valve 140 and supplies the water from the second introduction path 110b. Tap water is introduced into the road 130. Therefore, the water supplied from the tank 100 and the tap water supplied from the second introduction path 110b are mixed in the supply path 130. The control unit adjusts the opening degree of the mixing valve 140 so that the temperature of the water supplied to the hot water utilization point matches the set temperature of the hot water supply. On the other hand, the control unit operates the combustor 200 when the temperature of the water supplied from the tank 100 to the supply path 130 is lower than the hot water supply set temperature. Therefore, the water passing through the supply path 130 is heated by the combustor 200. The control unit controls the output of the combustor 200 so that the temperature of the water supplied to the hot water utilization point matches the set temperature of the hot water supply.

In this embodiment, the heat pump control unit 80 executes a normal control process (not shown) and a current value control process (see FIG. 3) in parallel when the operation of the heat pump 40 is started. That is, the heat pump 40 is operated while the normal control process is executed as the main process, and the operation of the heat pump 40 is corrected by using the result of the current value control process. Hereinafter, each process will be described.

(Normal control processing)
The normal control process is a process executed by the heat pump control unit 80 to heat the water in the tank 100 to a predetermined boiling set temperature (for example, 45 ° C.). When the heat pump 40 starts operating (that is, the compressor 44 and the fan 43 start operating) and the circulation pump 72 rotates to perform the heat storage operation, the heat pump control unit 80 starts normal control. The heat pump control unit 80 monitors the detection temperatures TH5, TH7, TH8 of the thermistors 60, 64, 66, and the hot water temperature TH8 (that is, the temperature of the hot water after heating by the heat pump 40) is equal to or higher than the predetermined boiling set temperature. To monitor. When the hot water temperature TH8 is lower than the boiling set temperature (for example, immediately after the start of operation of the heat pump 40 or when the water inlet temperature TH7 suddenly drops), the heat pump control unit 80 increases the rotation speed of the compressor 44 (that is, when it suddenly drops). It is determined that the situation requires an increase in the heating capacity by the heat pump 40). In this case, if the increase in the rotation speed is permitted in the current value control process (FIG. 3) described later (S80), the heat pump control unit 80 increases the rotation speed of the compressor 44. The heat pump control unit 80 also monitors that the hot water temperature TH8 exceeds the boiling set temperature by a predetermined threshold value or more (for example, 10 ° C. or more). When the hot water temperature TH8 exceeds the boiling set temperature by a predetermined threshold value or more (for example, when the water inlet temperature TH7 suddenly rises), the heat pump control unit 80 needs to reduce the rotation speed of the compressor 44. Judge. In this case, the heat pump control unit 80 reduces the rotation speed of the compressor 44. As described above, in the normal control process, the heat pump control unit 80 reaches a predetermined boiling set temperature (for example, 45 ° C.) while increasing or decreasing the rotation speed of the compressor 44 as necessary. To heat. The heat pump control unit 80 continuously executes the above-mentioned normal control process while the heat pump 40 is operating.

(Current value control processing)
Subsequently, the contents of the current value control process will be described with reference to FIG. In the current value control process, the system operating current value, which is the total value of the currents flowing through the hot water supply system 2 (that is, the heat pump unit 4, the tank unit 6, and the combustor unit 8) during the operation of the heat pump 40, is the outdoor outlet 16. In order to suppress the situation where the rated current (for example, 15A) is exceeded, the working current value of the heat pump unit 4 used by being connected to one of the outlets of the outdoor outlet 16 (hereinafter referred to as "unit working current value"). This is a process executed by the heat pump control unit 80 so that the maximum value (which may be referred to below as “regulated current”; for example, 10 A) is not exceeded. When the heat pump 40 starts operating (that is, the compressor 44 and the fan 43 start operating) and the circulation pump 72 rotates in order to perform the heat storage operation, the heat pump control unit 80, together with the above-mentioned normal control, is shown in FIG. The current value control process is started.

In S10, the heat pump control unit 80 specifies the current value used by the heat pump unit 4 at this point in time (that is, the “current value used by the unit”). Specifically, the heat pump control unit 80 detects the working current value of each element device of the heat pump unit 4, and totals them to specify the unit working current value. In another example, the heat pump control unit 80 may specify the unit working current value by detecting the total working current value of the heat pump unit 4.

In S20, the heat pump control unit 80 determines whether or not it is necessary to increase the rotation speed of the compressor 44 of the heat pump 40. Specifically, the heat pump control unit 80 determines whether or not it is determined in the above-mentioned normal control process that the rotation speed of the compressor 44 needs to be increased. When it is determined that the rotation speed of the compressor 44 needs to be increased, the heat pump control unit 80 determines YES in S20 and proceeds to S30. On the other hand, when it is determined that the situation does not require an increase in the rotation speed of the compressor 44, the heat pump control unit 80 determines NO in S20 and returns to S10.

In S30, the heat pump control unit 80 specifies a predicted increase value, which is an increase value of the unit used current value when the rotation speed of the compressor 44 is increased.

Specifically, in S30, the heat pump control unit 80 specifies a predicted increase value when the rotation speed is increased by a predetermined number (for example, 200 rpm) according to the rotation speed of the compressor 44 at the present time. The magnitude of the predicted increase value according to the range of the rotation speed before and after the increase is predetermined based on the experimental results and the like. For example, when the rotation speed before the increase is 2200 rpm and the rotation speed after the increase is 2400 rpm, the predicted increase value is 0.25 A. Further, for example, when the rotation speed before the increase is 2600 rpm and the rotation speed after the increase is 2800 rpm, the predicted increase value is 0.30 A. Further, for example, when the rotation speed before the increase is 3000 rpm and the rotation speed after the increase is 3200 rpm, the predicted increase value is 0.40 A.

In another example, the heat pump control unit 80 may further specify a predetermined predicted rise value in consideration of the outside air temperature (TH6), the incoming water temperature (TH7), the boiling set temperature, and the like.

For example, in general, in the heat pump 40, even if the rotation speed of the compressor 44 before and after the increase is the same, as the outside air temperature and the incoming water temperature become higher, the operating pressure of the compressor 44 becomes higher and the working current value becomes higher. It tends to be higher. Therefore, for example, when the outside air temperature is 25 ° C, the incoming water temperature is 24 ° C, and the boiling set temperature is 45 ° C (that is, assuming summer), the rotation speed before the increase is 2200 rpm, and the rotation speed after the increase is At 2400 rpm, the heat pump control unit 80 may specify the predicted rise value as 0.29 A. Further, for example, when the outside air temperature is 16 ° C., the incoming water temperature is 17 ° C., and the boiling set temperature is 45 ° C. (that is, the intermediate period), the rotation speed before the increase is 2200 rpm and the rotation speed after the increase is 2400 rpm. If this is the case, the heat pump control unit 80 may specify the predicted increase value as 0.27A. Further, for example, when the outside air temperature is 7 ° C., the incoming water temperature is 9 ° C., and the boiling set temperature is 45 ° C. (that is, in winter), the rotation speed before the increase is 2200 rpm and the rotation speed after the increase is 2400 rpm. In some cases, the heat pump control unit 80 may specify the predicted rise value as 0.25A.

Further, in general, in the heat pump 40, even when the rotation speed of the compressor 44 before and after the increase is the same, the higher the boiling set temperature, the higher the operating pressure of the compressor 44 and the higher the working current value. Tend to be. For example, when the outside air temperature is 7 ° C, the incoming water temperature is 9 ° C, and the boiling set temperature is 45 ° C, the rotation speed before the increase is 2200 rpm and the rotation speed after the increase is 2400 rpm, the heat pump control unit. 80 may specify the predicted increase value as 0.25A. On the other hand, for example, when the outside air temperature is 7 ° C., the incoming water temperature is 9 ° C., and the boiling set temperature is 65 ° C., the rotation speed before the increase is 2200 rpm and the rotation speed after the increase is 2400 rpm, the heat pump. The control unit 80 may specify the predicted increase value as 0.40 A.

In the following S40, the heat pump control unit 80 determines whether or not the total value of the unit operating current value specified in S10 and the predicted rising value specified in S30 is equal to or higher than a predetermined first threshold value. The first threshold value is the upper limit of the system working current value, which is the total working current value of the hot water supply system 2 (that is, the heat pump unit 4, the tank unit 6, and the combustor unit 8) that receives power from the outdoor outlet 16. It is a value smaller than the first upper limit value. In this embodiment, it is assumed that the rated current of the outdoor outlet 16 is 15 A and the specified current of the heat pump unit 4 is 10 A. In this embodiment, the first upper limit value is 10A and the first threshold value is 9A. The first threshold value (9A) can be rephrased as a value obtained by subtracting a predetermined first correction value (1A) from the first upper limit value (10A). Further, in this embodiment, the first upper limit value is the same value (10A) as the specified current value of the heat pump unit 4, but in other examples, the first upper limit value is a value equal to or less than the rated current of the outdoor outlet 16. If there is, it may be any value (for example, the same value as the rated current).

When the total value of the unit used current value and the predicted increase value is equal to or higher than the first threshold value, the heat pump control unit 80 determines YES in S40 and proceeds to S50. On the other hand, when the total value of the unit used current value and the predicted increase value is lower than the first threshold value, the heat pump control unit 80 determines NO in S40 and proceeds to S80. In S80, the heat pump control unit 80 permits an increase in the rotation speed of the compressor 44. After finishing S80, the heat pump control unit 80 returns to S10.

In S50, the heat pump control unit 80 maintains (that is, does not increase) the rotation speed of the compressor 44.

In the following S60, the heat pump control unit 80 determines whether or not the hot water temperature (TH8) is lower than the boiling set temperature. When the hot water temperature is higher than the boiling set temperature (that is, when the heating capacity of the heat pump 40 is not insufficient), the heat pump control unit 80 determines NO in S60 and returns to S10. On the other hand, when the hot water temperature is lower than the boiling set temperature (that is, when the heating capacity of the heat pump 40 is insufficient), the heat pump control unit 80 determines YES in S60 and proceeds to S70.

In S70, the heat pump control unit 80 reduces the rotation speed of the circulation pump 72 during operation. As a result, the flow rate of water circulating in the tank water circulation path 70 is reduced. As a result, the flow rate of the hot water heated by the condenser 45 also decreases, but the hot water temperature can be raised to a temperature equal to or higher than the boiling set temperature. Hot water having a temperature equal to or higher than the boiling set temperature can be stored in the tank 100. After finishing S70, the heat pump control unit 80 returns to S10.

The heat pump control unit 80 continuously executes each of the above processes S10 to S80 while the heat pump 40 is operating.

(Action and effect of the first embodiment)
The configuration and operation of the hot water supply system 2 of this embodiment have been described above. As described above, in the present embodiment, in the heat pump control unit 80, in the situation where the rotation speed of the compressor 44 of the heat pump 40 needs to be increased (YES in S20), the total value of the unit used current value and the predicted increase value is When it is determined that the threshold value is equal to or higher than the first threshold value (9A in this embodiment) (YES in S40), the rotation speed is maintained without being increased (S50). As a result, it is possible to suppress an increase in the current value used by the unit. As a result, it is possible to prevent the system operating current value from exceeding the first upper limit value (10 A (value of the specified current of the heat pump unit 4 in this embodiment)). That is, according to the hot water supply system 2 of the present embodiment, by appropriately setting the first threshold value and the first upper limit value, it is appropriate that the current flowing through the hot water supply system 2 exceeds the rated current of the outdoor outlet 16. Can be suppressed.

The correspondence between this embodiment and the description of the claims is described. The heat pump unit 4 is an example of the "first unit", and the combination of the tank unit 6 and the combustor unit 8 is an example of the "second unit". Wiring 20 is an example of the "first power supply system", and wirings 22 and 23 are examples of the "second power supply system". The process executed in S50 is an example of "maintenance control".

(Second Example)
The second embodiment will be described with reference to FIG. Since this embodiment is a modification of the first embodiment, the points different from those of the first embodiment will be mainly described. In this embodiment, a part of the contents of the current value control process executed by the heat pump control unit 80 is different from that in the first embodiment. Specifically, as shown in FIG. 4, the heat pump control unit 80 differs from the first embodiment in that the heat pump control unit 80 proceeds to the process of S15 after specifying the unit working current value in S10. In FIG. 4, the same process as that of the first embodiment (FIG. 3) is represented by using the same step number.

In S15, the heat pump control unit 80 determines whether or not the unit working current value specified in S10 is equal to or greater than the first threshold value. If the unit working current value is equal to or higher than the first threshold value at the time of S15, the heat pump control unit 80 determines YES in S15 and proceeds to S16. In S16, the heat pump control unit 80 reduces the rotation speed of the compressor 44 by a predetermined number (for example, 200 rpm). After finishing S16, the heat pump control unit 80 returns to S10. On the other hand, if the unit working current value is lower than the first threshold value at the time of S15, the heat pump control unit 80 determines NO in S15 and proceeds to S20. Since each process of S20 to S80 is the same as that of the first embodiment, detailed description thereof will be omitted.

(Action and effect of the second embodiment)
As described above, in this embodiment, when the current value used by the unit during the operation of the heat pump 40 is equal to or higher than the first threshold value (YES in S15), the rotation speed of the compressor 44 is reduced (S16). By reducing the rotation speed of the compressor 44, the current value used by the unit can be reduced. As a result, the unit working current value may be lower than the first threshold value (9A in this embodiment). Accordingly, the system operating current value may be lower than the first upper limit value (10 A in this embodiment). That is, according to this embodiment, even when the unit working current value becomes equal to or higher than the first threshold value, the occurrence of a situation in which the current flowing through the hot water supply system 2 exceeds the rated current of the outdoor outlet 16 is appropriately suppressed. Can be done. The process of S16 of this embodiment is an example of "decrease control".

(Third Example)
The third embodiment will be described with reference to FIG. Since this embodiment is a modification of the second embodiment, the points different from those of the second embodiment will be mainly described. Also in this embodiment, a part of the content of the current value control process is different from that of the second embodiment. Specifically, as shown in FIG. 5, in this embodiment, the heat pump control unit 80 proceeds to the process of S12 after specifying the unit used current value in S10, which is different from the second embodiment. Also in FIG. 5, the same processes as those of the first embodiment (FIG. 3) and the second embodiment (FIG. 4) are represented by using the same step numbers.

In S12, the heat pump control unit 80 determines whether or not the unit working current value specified in S10 is equal to or higher than a predetermined second threshold value. The second threshold value is a value smaller than the above-mentioned first upper limit value and a value larger than the first threshold value. In this embodiment as well, it is assumed that the rated current of the outdoor outlet 16 is 15 A and the specified current of the heat pump unit 4 is 10 A. Also in this embodiment, the first upper limit value is 10A and the first threshold value is 9A. Then, in this embodiment, the second threshold value is 9.8 A. The second threshold value (9.8A) can be rephrased as a value obtained by subtracting a predetermined second correction value (0.2A) from the first upper limit value (10A).

If the unit working current value is equal to or higher than the second threshold value at the time of S12, the heat pump control unit 80 determines YES in S12 and proceeds to S13. In S13, the heat pump control unit 80 stops the compressor 44. At this time, the heat pump control unit 80 also stops the fan 43 and the circulation pump 72. As a result, the heat pump 40 stops operating, and the heat storage operation ends. After finishing S13, the heat pump control unit 80 ends the current value control process of FIG. The heat pump control unit 80 also terminates the normal control process that was executed in parallel with the current value control process. When the heat storage heat storage is started again and the heat pump 40 starts operating again, the heat pump control unit 80 starts the normal processing and the current value control processing again.

On the other hand, if the unit working current value is lower than the second threshold value at the time of S12, the heat pump control unit 80 determines NO in S12 and proceeds to S15. Since each process of S15 to S80 is the same as that of the second embodiment, detailed description thereof will be omitted.

(Action and effect of the third embodiment)
In this embodiment, the heat pump control unit 80 stops the compressor 44 of the heat pump 40 when the unit working current value is equal to or higher than the second threshold value (YES in S12). By stopping the compressor 44, it is possible to suppress the occurrence of a situation in which the unit used current value exceeds the first upper limit value (10 A in this embodiment). That is, according to this embodiment, the unit working current value becomes equal to or higher than the second threshold value by appropriately setting the second threshold value (9.8A in this embodiment) and the first upper limit value. However, it is possible to appropriately suppress the occurrence of a situation in which the current flowing through the hot water supply system 2 exceeds the rated current of the outdoor outlet 16. The process of S13 of this embodiment is an example of "stop control".

(Fourth Example)
The fourth embodiment will be described with reference to FIGS. 6 to 8. Since this embodiment is a modification of the third embodiment, the points different from those of the third embodiment will be mainly described. Also in this embodiment, a part of the content of the current value control process is different from that in the third embodiment. Also in FIG. 6, the same processes as those of the first embodiment (FIG. 3), the second embodiment (FIG. 4), and the third embodiment (FIG. 5) are represented by using the same step numbers. As shown in FIG. 6, in this embodiment, when the heat pump control unit 80 determines NO in S15, the process proceeds to S120 instead of S20 (see FIG. 5). In S120, the heat pump control unit 80 executes the predicted current value difference calculation process (see FIG. 7). The predicted current value difference is the difference between the predicted value of the previous unit used current value calculated by the heat pump control unit 80 and the predicted value of the current unit used current value. By summing the unit working current value and the predicted current value difference, the predicted value of the unit working current value after the change can be obtained with high accuracy. The details of the predicted current value difference calculation process will be described in detail later (see FIG. 7). When the predicted current value difference calculation process is completed in S120 and the predicted current value difference is calculated, the heat pump control unit 80 proceeds to S140.

In S140, the heat pump control unit 80 determines whether or not the total value of the unit used current value specified in S10 and the predicted current value difference calculated in the predicted current value difference calculation process of S120 is equal to or higher than the first threshold value. To judge. When the total value of the unit used current value and the predicted current value difference is equal to or greater than the first threshold value, the heat pump control unit 80 determines YES in S140 and proceeds to S150. In S150, the heat pump control unit 80 changes the operating state of the elemental equipment determined to be necessary (here, for example, an increase in the rotation speed of the compressor 44, an increase in the rotation speed of the fan 43, and rotation of the circulation pump 72). Maintain the operating state of the element equipment without executing (changes that accompany an increase in the current value used, such as an increase in the number). After finishing S150, the process proceeds to S60. Since the subsequent processing contents of S60 and S70 are the same as those of the first embodiment, detailed description thereof will be omitted.

On the other hand, when the total value of the unit used current value and the predicted current value difference is lower than the first threshold value, the heat pump control unit 80 determines NO in S140 and proceeds to S180. In S180, the heat pump control unit 80 changes the operating state of the elemental equipment determined to be necessary (here, the rotation speed of the compressor 44 is increased or decreased, the rotation speed of the fan 43 is increased or decreased, and the opening degree of the expansion valve 46 is changed. Changes in the operating state of all elemental equipment, such as changes and increases / decreases in the rotation speed of the circulation pump 72) are permitted. After finishing S180, the heat pump control unit 80 returns to S10.

(Predicted current value difference calculation process)
Subsequently, the contents of the predicted current value difference calculation process (S120 in FIG. 6) will be described with reference to FIG. 7. The predicted current value difference calculation process is based on the temperature of each part of the heat pump unit 4 (that is, TH1 to TH8) and the state of each element device (compressor 44, expansion valve 46, fan 43, circulation pump 72, etc.). This is a process for calculating the predicted current value difference that represents the amount of change (increase / decrease) in the predicted value of the unit used current value.

In S200, the heat pump control unit 80 specifies the temperature of each unit of the heat pump unit 4 at this time. Specifically, in S200, the heat pump control unit 80 specifies each detection temperature (TH1 to TH8) of the thermistors 52 to 66.

In the following S202, the heat pump control unit 80 determines whether or not it is necessary to change the operating state of any of the element devices of the heat pump unit 4. Specifically, the heat pump control unit 80 is in a situation where it is necessary to change the heating capacity by the heat pump 40 or the flow rate of the water to be heated in the above-mentioned normal control process, and the operating state of any of the elemental devices is in the operating state. If it is determined that the change is necessary, the heat pump control unit 80 determines YES in S202 and proceeds to S220. On the other hand, when it is determined that it is not necessary to change the operating state of the element device, the heat pump control unit 80 determines NO in S202 and proceeds to S204.

In S204, the heat pump control unit 80 specifies the state of each element device of the heat pump unit 4 at this time. Specifically, the heat pump control unit 80 specifies the rotation speed of the compressor 44, the opening degree of the expansion valve 46, the rotation speed of the fan 43, and the rotation speed of the circulation pump 72. After finishing S204, the heat pump control unit 80 proceeds to S206.

On the other hand, in S220, the heat pump control unit 80 specifies the state of each element device of the heat pump unit 4 at this time, and also specifies the content of the change in the operating state of the element device to be performed. Next, in S222, the heat pump control unit 80 executes a temperature correction process (see FIG. 8). The temperature correction process is a part of each temperature value specified in S200 (specifically, TH1, TH2, TH4, TH5) on the assumption that the change in the operating state of the element device to be performed is reflected. This is a process for correcting at least one of them). The corrected temperature value is reflected in the calculation executed after S206. The details of the temperature correction process will be described later (see FIG. 8). When the temperature correction process is completed in S222, the heat pump control unit 80 proceeds to S206.

In S206, the heat pump control unit 80 calculates the compressor input Qc (unit: W). The compressor input Qc is calculated using the values of each temperature of TH1, TH2, TH4, and TH5. When TH1, TH2, TH4, and TH5 are the corrected values by the temperature correction process, the compressor input Qc is calculated using the corrected temperature values.

Specifically, in S206, the heat pump control unit 80 calculates the compressor input Qc by the following procedure. First, the heat pump control unit 80 identifies the values of enthalpy h1 and h2 using the values of each temperature of TH1, TH2, TH4, and TH5 and the known Moriel diagram (that is, the ph diagram). The value of h2-h1 (that is, the work amount of the compressor 44) is calculated. Then, the heat pump control unit 80 substitutes the rotation speed of the compressor 44 into a predetermined function to calculate the refrigerant circulation amount. At this time, when it is necessary to change the rotation speed of the compressor 44, the heat pump control unit 80 substitutes the changed rotation speed into a predetermined function to calculate the refrigerant circulation amount. Next, the heat pump control unit 80 calculates the compressor input Qc by calculating the product of the refrigerant circulation amount and the value of h2-h1.

In the following S208, the heat pump control unit 80 calculates the circulation pump input Qp (unit: W). The circulation pump input Qp is calculated by substituting the rotation speed of the circulation pump 72 and the value of the temperature value TH7 (that is, the water entry temperature) into a predetermined function. At this time, when it is necessary to change the rotation speed of the circulation pump 72, the heat pump control unit 80 substitutes the changed rotation speed into a predetermined function to calculate the circulation pump input Qp.

In the following S210, the heat pump control unit 80 calculates the fan input Qf (unit: W). The fan input Qf is calculated by substituting the rotation speed of the fan 43 and the value of the temperature value TH6 (that is, the outside air temperature) into a predetermined function. At this time, when it is necessary to change the rotation speed of the fan 43, the heat pump control unit 80 substitutes the changed rotation speed into a predetermined function to calculate the fan input Qf.

As described above, the heat pump control unit 80 executes each process of S206 to S210, and calculates the compressor input Qc, the circulation pump input Qp, and the fan input Qf, respectively. The heat pump control unit 80 does not calculate the expansion valve input. This is because the operating time of the expansion valve 46 is short, the influence on the current value used by the unit is small, and the need for consideration is small.

In S212, the heat pump control unit 80 calculates and stores the predicted current value I. The predicted current value I is calculated by dividing the total value of the compressor input Qc, the circulation pump input Qp, and the fan input Qf by the power supply voltage V (100 V in this embodiment). When the heat pump control unit 80 calculates the predicted current value I, the heat pump control unit 80 stores the calculated predicted current value I.

In S214, the heat pump control unit 80 calculates the predicted current value difference. Specifically, in S214, the heat pump control unit 80 calculates the predicted current value difference by obtaining the difference between the previously stored predicted current value I and the predicted current value I stored in S212. When the predicted current value difference is calculated in S214, the heat pump control unit 80 ends the predicted current value difference calculation process of FIG. 7 (S120 of FIG. 6).

(Temperature correction processing)
Subsequently, the contents of the temperature correction process will be described with reference to FIG. As described above, the temperature correction process is a part of each temperature value specified in S200 (specifically, TH1, TH2, and TH2, assuming that the change in the operating state of the elemental equipment to be performed is reflected. This is a process for correcting at least one of TH4 and TH5).

When the temperature correction process of FIG. 8 is started, the heat pump control unit 80 has S300, S302, S310, S312, S320, S322, S330, S332, Perform each judgment of. In the temperature correction process of FIG. 8, the heat pump control unit 80 determines that at least one of S300, S302, S310, S312, S320, S322, S330, and S332 is YES. The heat pump control unit 80 first executes the determination of S300 and 302.

In S300, the heat pump control unit 80 determines whether or not the change content of the element device is "increase in the rotation speed of the fan 43". When the content of the change of the element device is "increase in the rotation speed of the fan 43", the heat pump control unit 80 determines YES in S300 and proceeds to S304. In S304, the heat pump control unit 80 corrects (that is, rise correction) the value of the specified evaporation temperature (TH4) higher by a predetermined value. This is because it is predicted that the amount of heat absorbed from the outside air will increase as the rotation speed of the fan 43 increases. After finishing S304, the heat pump control unit 80 proceeds to the processing after S310.

In S302, it is determined whether or not the content of the change of the element device is "decrease in the rotation speed of the fan 43". When the content of the change of the element device is "decrease in the rotation speed of the fan 43", the heat pump control unit 80 determines YES in S302 and proceeds to S306. In S306, the heat pump control unit 80 corrects the specified evaporation temperature (TH4) value lower by a predetermined value (that is, lowering correction). This is because it is predicted that the amount of heat absorbed from the outside air will decrease as the rotation speed of the fan 43 decreases. After finishing S306, the heat pump control unit 80 proceeds to the process after S310.

Further, even when the heat pump control unit 80 determines NO in any of S300 and S302 (that is, when the change content does not relate to the rotation speed of the fan 43), the heat pump control unit 80 proceeds to the processing after S310.

Subsequently, the heat pump control unit 80 executes the determination of S310 and 312. In S310, it is determined whether or not the content of the change of the element device is "increase in the rotation speed of the circulation pump 72". When the content of the change of the element device is "increase in the rotation speed of the circulation pump 72", the heat pump control unit 80 determines YES in S310 and proceeds to S314. In S314, the heat pump control unit 80 lowers and corrects the value of the specified condensation temperature (TH5). This is because when the rotation speed of the circulation pump 72 increases, the flow rate of water sent from the tank 100 to the condenser 45 increases, and the amount of heat dissipated to the water increases. After finishing S314, the heat pump control unit 80 proceeds to the processing after S320.

In S312, it is determined whether or not the content of the change of the element device is "decrease in the rotation speed of the circulation pump 72". When the content of the change of the element device is "decrease in the rotation speed of the circulation pump 72", the heat pump control unit 80 determines YES in S312 and proceeds to S316. In S316, the heat pump control unit 80 raises and corrects the value of the specified condensation temperature (TH5). This is because when the rotation speed of the circulation pump 72 decreases, the flow rate of water sent from the tank 100 to the condenser 45 decreases, and the amount of heat dissipated to the water decreases. After finishing S316, the heat pump control unit 80 proceeds to the processing after S320.

Further, even if the heat pump control unit 80 determines NO in any of S310 and S312 (that is, the change content does not relate to the rotation speed of the circulation pump 72), the heat pump control unit 80 proceeds to the processing after S320.

Subsequently, the heat pump control unit 80 executes the determination of S320 and 322. In S320, it is determined whether or not the content of the change of the element device is "increase in the opening degree of the expansion valve 46". When the content of the change of the element device is "increase in the opening degree of the expansion valve 46", the heat pump control unit 80 determines YES in S320 and proceeds to S324. In S324, the heat pump control unit 80 lower-corrects the specified condensation temperature (TH5) value, raises the evaporation temperature (TH4) value, and lower-corrects the compressor discharge temperature (TH1) value. , The value of the compressor suction temperature (TH2) is corrected to decrease. In FIG. 8, the compressor discharge temperature and the compressor suction temperature are abbreviated as “discharge temperature” and “suction temperature”, respectively. This is because when the opening degree of the expansion valve 46 increases, the flow rate of the refrigerant passing through the expansion valve 46 increases. After finishing S324, the heat pump control unit 80 proceeds to the process after S330.

In S322, it is determined whether or not the content of the change of the element device is "decrease in the opening degree of the expansion valve 46". When the content of the change of the element device is "decrease in the opening degree of the expansion valve 46", the heat pump control unit 80 determines YES in S322 and proceeds to S326. In S326, the heat pump control unit 80 corrects the value of the specified condensation temperature (TH5) to rise, corrects the value of the evaporation temperature (TH4) to fall, and corrects the value of the compressor discharge temperature (TH1) to rise. , The value of the compressor suction temperature (TH2) is corrected to increase. This is because when the opening degree of the expansion valve 46 decreases, the flow rate of the refrigerant passing through the expansion valve 46 decreases. After finishing S326, the heat pump control unit 80 proceeds to the processing after S330.

Further, even when the heat pump control unit 80 determines NO in either S320 or S322 (that is, when the change content does not relate to the opening degree of the expansion valve 46), the heat pump control unit 80 proceeds to the processing after S330.

Subsequently, the heat pump control unit 80 executes the determination of S330 and 332. In S330, it is determined whether or not the content of the change of the element device is "increase in the rotation speed of the compressor 44". When the content of the change of the element device is "increase in the rotation speed of the compressor 44", the heat pump control unit 80 determines YES in S330 and proceeds to S334. In S334, the heat pump control unit 80 corrects the value of the specified condensation temperature (TH5) to rise, corrects the value of the evaporation temperature (TH4) to fall, and corrects the value of the compressor discharge temperature (TH1) to rise. , The value of the compressor suction temperature (TH2) is corrected to decrease. This is because as the rotation speed of the compressor 44 increases, the temperature rise range of the refrigerant in the compressor 44 increases. After finishing S334, the heat pump control unit 80 ends the process of FIG.

In S332, it is determined whether or not the content of the change of the element device is "decrease in the rotation speed of the compressor 44". When the content of the change of the element device is "decrease in the rotation speed of the compressor 44", the heat pump control unit 80 determines YES in S332 and proceeds to S336. In S336, the heat pump control unit 80 lower-corrects the specified condensation temperature (TH5) value, raises the evaporation temperature (TH4) value, and lower-corrects the compressor discharge temperature (TH1) value. , The value of the compressor suction temperature (TH2) is corrected to increase. This is because when the rotation speed of the compressor 44 decreases, the temperature rise range of the refrigerant in the compressor 44 decreases. After finishing S336, the heat pump control unit 80 ends the process of FIG.

Further, the heat pump control unit 80 ends the process of FIG. 8 even when it is determined to be NO in any of S330 and S332 (that is, when the change content does not relate to the rotation speed of the compressor 44).

(Action and effect of the fourth embodiment)
The configuration and operation of the hot water supply system 2 of this embodiment have been described above. As described above, in the present embodiment, the heat pump control unit 80 executes the processes shown in FIGS. 7 and 8 to control the operating state of each element device and the temperature of each part of the heat pump unit 4 (TH1 to TH8). Based on the current state of the heat pump unit 4, the predicted current value difference, which is the amount of change in the unit operating current value when the operating state of the element device is changed in a situation where it is necessary to change the operating state of the element device. Can be calculated appropriately. Then, the heat pump control unit 80 compares the total value of the unit used current value and the predicted current value difference with the first threshold value. At the time of this comparison, the heat pump control unit 80 uses the predicted current value difference, which is the difference between the previous predicted current value and the current predicted current value. Therefore, even if the calculation accuracy of the predicted current value for each time is not so high, the predicted current value difference, which is the difference from the previous time, can be specified with relatively high accuracy. The total value of the unit used current value and the predicted current value difference can be appropriately compared with the first threshold value. Therefore, in this embodiment, the heat pump control unit 80 compares the total value of the unit used current value and the predicted current value difference with the first threshold value (S140 in FIG. 6) to change the operating state of the element device. By switching (S150, S180) whether or not to allow the current to flow, it is possible to appropriately suppress the occurrence of a situation in which the current flowing through the hot water supply system 2 exceeds the rated current of the outdoor outlet 16.

(Fifth Example)
A fifth embodiment will be described with reference to FIGS. 9 and 10. Since this embodiment is a modification of the third embodiment, the points different from those of the third embodiment will be mainly described. Also in this embodiment, a part of the content of the current value control process is different from that in the third embodiment. Specifically, as shown in FIG. 9, in this embodiment, after the heat pump control unit 80 specifies the unit operating current value in S10 and before proceeding to the processing in S12, the threshold correction processing (FIG. 10) is executed, which is different from the third embodiment. Also in FIG. 9, the same process as that of the third embodiment (FIG. 5) is represented by using the same step number. The threshold value correction process (see FIG. 10) executed in S11 is a process for determining the values of the first threshold value and the second threshold value used in each subsequent process (that is, each determination of S12, S15, and S40). Is. That is, in this embodiment, each determination of S12, S15, and S40 is executed using the values of the first threshold value and the second threshold value determined by the threshold value correction process of S11.

(Threshold correction processing)
Subsequently, the contents of the threshold value correction process (S11 in FIG. 9) will be described with reference to FIG. In S400, the heat pump control unit 80 specifies the current values used by all the devices. The current value used by all devices means all the terminal devices connected to the branch circuit (hereinafter sometimes referred to as "specific branch circuit") branched by the branch breaker 14a (that is, the terminal device 19 in FIG. 1). It is the total value of the current values used by the heat pump unit 4, the tank unit 6, and the combustor unit 8. in the following, it may be referred to as “all equipment”). In S400, the heat pump control unit 80 can specify the current value used by all devices by communicating with the distribution board control unit (not shown) provided on the distribution board 11.

In the following S402, the heat pump control unit 80 specifies the system operating current value. As described above, the system working current value is the working current value of the hot water supply system 2 (that is, the heat pump unit 4, the tank unit 6, and the combustor unit 8). In S402, the heat pump control unit 80 specifies the current values used in the tank unit 6 and the combustor unit 8 by communicating with the tank control unit 180 and the combustor control unit 280. Then, the heat pump control unit 80 totals the unit working current value specified in S10 (see FIG. 9) and the working current value in the tank unit 6 and the combustor unit 8 to specify the system working current value.

In the following S404, the heat pump control unit 80 specifies the current value used outside the system. The current value used outside the system is the device (in the example of FIG. 1, the terminal) excluding the hot water supply system 2 (that is, the heat pump unit 4, the tank unit 6, and the combustor unit 8) among all the devices connected to the specific branch circuit. It is the working current value of the device 19. (in the following, it may be referred to as “device outside the system”). Therefore, in S404, the heat pump control unit 80 specifies a value excluding the current value used for all devices specified in S400 and the current value used in the system specified in S402 as the current value used outside the system.

In the following S406, the heat pump control unit 80 calculates the second upper limit value. The second upper limit value is a value obtained by subtracting the out-of-system current use value specified in S404 from the all device upper limit value which is the upper limit value of the current use value of all the devices. In this embodiment, the upper limit of all equipment is set to 20A, which is the rated current of the specific branch circuit (that is, the operating current of the branch breaker 14a), but in other examples, the upper limit of all equipment is other than this. It may be a value. For example, when the current value used outside the system is 12A, in S406, the heat pump control unit 80 has a second upper limit of 8A, which is a value obtained by subtracting 12A (current value used outside the system) from 20A (upper limit value of all equipment). Calculate as a value.

In S408, the heat pump control unit 80 determines whether or not the second upper limit value calculated in S406 is equal to or less than the predetermined first upper limit value. In this embodiment as well, the first upper limit value is set to 10A, but in other examples, the first upper limit value may be another value. When the second upper limit value is equal to or less than the first upper limit value (10A in this embodiment) (for example, when the second upper limit value is 8A), the heat pump control unit 80 determines YES in S408 and proceeds to S410. On the other hand, when the second upper limit value is larger than the first upper limit value (10A in this embodiment) (for example, when the second upper limit value is 15A), the heat pump control unit 80 determines NO in S408 and proceeds to S420. ..

In S410, the heat pump control unit 80 calculates the first threshold value by removing the predetermined first correction value (for example, 1A) from the second upper limit value. For example, when the second upper limit value is 8A, the first threshold value calculated by S410 is 7A.

In the following S412, the heat pump control unit 80 calculates the second threshold value by removing the predetermined second correction value (for example, 0.2A) from the second upper limit value. For example, when the second upper limit value is 8A, the second threshold value calculated in S412 is 7.8A. When S412 is completed, the heat pump control unit 80 ends the threshold value correction process of FIG. In this case, the heat pump control unit 80 executes each process of S12, S15, and S40 in FIG. 9 using the first threshold value and the second threshold value calculated in S410 and S412.

On the other hand, in S420, the heat pump control unit 80 calculates the first threshold value by removing the predetermined first correction value (for example, 1A) from the predetermined first upper limit value. In this embodiment, since the first upper limit value is 10A, the first threshold value calculated in S420 is 9A.

In the following S422, the heat pump control unit 80 calculates the second threshold value by removing the predetermined second correction value (for example, 0.2A) from the first upper limit value. In this embodiment, since the first upper limit value is 10A, the second threshold value calculated in S420 is 9.8A. When S422 is completed, the heat pump control unit 80 ends the threshold value correction process of FIG. In this case, the heat pump control unit 80 executes each process of S12, S15, and S40 in FIG. 9 using the first threshold value and the second threshold value calculated in S420 and S422.

(Action and effect of the fifth embodiment)
In this embodiment, the heat pump control unit 80 executes a threshold value correction process (see FIG. 10) to calculate a first threshold value and a second threshold value. Therefore, even when the current value used outside the system is large, the hot water supply system 2 can be operated while suppressing the current value used in the system from becoming equal to or higher than the second upper limit value (YES, S410, in S408 of FIG. 10). S412). Therefore, according to this embodiment, all devices are used while suppressing that the current value used by all devices exceeds the upper limit value of all devices and that the current value used by the system exceeds the first upper limit value or the second upper limit value. The current value can be controlled. Therefore, it is possible to appropriately suppress the occurrence of a situation in which the current flowing through the hot water supply system 2 exceeds the rated current of the outdoor outlet 16 and a situation in which the branch breaker 14a cuts off the current.

(6th Example)
A sixth embodiment will be described with reference to FIG. Since this embodiment is a modification of the fourth embodiment, the differences from the fourth embodiment will be mainly described. Also in this embodiment, a part of the content of the current value control process is different from that of the fourth embodiment. Specifically, as shown in FIG. 11, in this embodiment as well, after the heat pump control unit 80 specifies the unit operating current value in S10 and before proceeding to the processing of S12, as in the fifth embodiment. , S11 is different from the fourth embodiment in that the threshold value correction process (see FIG. 10) is executed. Also in FIG. 11, the same processing as that of the fourth embodiment (FIGS. 6 to 8) is represented by using the same step number. In this embodiment, each determination of S12, S15, and S140 is executed using the values of the first threshold value and the second threshold value determined by the threshold value correction process of S11. Since the content of the threshold value correction process (see FIG. 10) executed in S11 is the same as that of the fifth embodiment, detailed description thereof will be omitted.

(Action and effect of the sixth embodiment)
In this embodiment as well, as in the fifth embodiment, the heat pump control unit 80 executes the threshold value correction process (see FIG. 10) to calculate the first threshold value and the second threshold value. Therefore, the hot water supply system 2 of the present embodiment can also exhibit the same effect as that of the fifth embodiment.

Although each embodiment has been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples exemplified above.

(Modification 1) Each value of the first upper limit value (10A), the first correction value (1A), the second correction value (0.2A), and the upper limit value of all devices (20A) described in each of the above embodiments. Are all examples. Each value of the first upper limit value, the first correction value, the second correction value, and the upper limit value of all devices may be other than those described above.

(Modification 2) In each of the above embodiments, the system working current value is the unit working current value (that is, the working current value of the heat pump unit 4) and the working current value of the tank unit 6 and the combustor unit 8. It is a total value. Not limited to this, the system working current value may be the total value of the unit working current value (that is, the working current value of the heat pump unit 4) and the working current value of one of the tank unit 6 and the combustor unit 8. .. Generally speaking, the "second unit" may include only one of a tank for storing water and a combustor for heating water.

(Modification 3) In the fourth and sixth embodiments described above, the heat pump control unit 80 executes the predicted current value difference calculation process of FIG. 7. That is, the heat pump control unit 80 calculates the predicted current value difference based on the temperature (TH1 to TH8) of each part of the heat pump unit 4 and the operating state of the element equipment. Not limited to this, the heat pump control unit 80 may calculate the predicted current value difference by using one of the temperature (TH1 to TH8) of each part of the heat pump unit 4 and the operating state of the element equipment. .. Generally speaking, the control device should increase the rotation speed by using the information of at least one of the temperature of each part of the first unit and the operating state of the elemental equipment of the first unit. The unit operating current value when the rotation speed is increased may be predicted.

(Modification 4) In the fourth and sixth embodiments described above, the heat pump control unit 80 compares the total value of the unit used current value and the predicted current value difference with the first threshold value (FIGS. 6 and 11). See S140). Not limited to this, in the fourth and sixth embodiments, the heat pump control unit 80 may compare the predicted current value (see S212 in FIG. 7) with the first threshold value.

(Modified Example 5) In each of the above embodiments, an example of a hot water supply system 2 that supplies hot water to a hot water utilization location (that is, supplies hot water) has been described. Not limited to this, the techniques disclosed herein may also be applied to heating systems used for heating. In that case, antifreeze is an example of a "heat medium". That is, the heat supply system is not limited to the hot water supply system, but may be a heating system.

The technical elements described herein or in the drawings exhibit their technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques exemplified in the present specification or the drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.

2: Hot water supply system 4: Heat pump unit 6: Tank unit 8: Combustor unit 10: Commercial power supply 11: Distribution board 12: Main breaker 14a: Branch breaker 14b: Branch breaker 14c: Branch breaker 16: Outdoor outlet 18: Indoor outlet 19: Terminal equipment 20: Wiring 22: Wiring 23: Wiring 24: Wiring 26: Wiring 27: Wiring 28: Wiring 40: Heat pump 41: Refrigerator circulation path 42: Evaporator 43: Fan 44: Compressor 45: Condenser 46: Expansion valve 52: Thermista (TH1)
54: Thermistor (TH2)
56: Thermistor (TH3)
58: Thermistor (TH4)
60: Thermistor (TH5)
62: Thermistor (TH6)
64: Thermistor (TH7)
66: Thermistor (TH8)
70: Tank water circulation path 72: Circulation pump 80: Heat pump control unit 100: Tank 102: Thermistor 104: Thermistor 106: Thermistor 108: Thermistor 110: Tap water introduction path 110a: First introduction path 110b: Second introduction path 112: Water supply Water supply source 130: Supply path 140 Mixing valve 180: Tank control unit 200: Combustor 210: Thermistor 280: Combustor control unit 500: Building

Claims (5)

A heat supply system that is installed in a building that has an outlet that receives power from a power source and operates by being connected to the outlet.
With the first unit
With the second unit
Equipped with a control device,
The first unit is
A heat pump equipped with a compressor, a condenser, a decompression mechanism, and an evaporator to heat a heat medium,
It has a first power supply system connected to the outlet, and has.
The second unit is
At least one of the tank that stores the heat medium and the combustor that heats the heat medium,
It has a second power system connected to the outlet, and has.
The control device is
In a situation where the rotation speed of the compressor should be increased during the operation of the heat pump, it is predicted that the unit working current value, which is the working current value of the first unit, will be equal to or higher than the first threshold value when the rotation speed is increased. If so, the maintenance control to maintain the rotation speed is executed, and
The first threshold value is smaller than the first upper limit value, which is the upper limit value of the system working current value, which is the total working current value of the first unit and the second unit.
Heat supply system. The control device further executes a reduction control for reducing the rotation speed when the current value used by the unit during the operation of the heat pump is equal to or higher than the first threshold value.
The heat supply system according to claim 1. The control device further executes a stop control for stopping the compressor when the current value used by the unit during the operation of the heat pump is equal to or higher than the second threshold value.
The second threshold value is a value smaller than the first upper limit value and a value larger than the first threshold value.
The heat supply system according to claim 1 or 2. The control device uses information on at least one of the temperature of each part of the first unit and the operating state of the elemental equipment of the first unit to rotate the rotation speed in a situation where the rotation speed should be increased. Predicting the current value of the unit when the number is increased,
The heat supply system according to any one of claims 1 to 3. The building is connected to the power source and has one or more branch circuits for branching the power supplied from the power source.
The outlet is connected to a specific branch circuit among the one or more branch circuits, and receives power from the power source via the specific branch circuit.
The control device further
From the upper limit of all equipment, which is the upper limit of the total current value of all equipment supplied via the specific branch circuit, the total current value of equipment outside the system excluding the first unit and the second unit. Calculate the second upper limit value that is the excluded value,
When the calculated second upper limit value is equal to or less than the first upper limit value, the compressor is operated so that the system working current value is lower than the second upper limit value.
When the calculated second upper limit value is larger than the first upper limit value, the compressor is operated so that the system working current value is lower than the first upper limit value.
The heat supply system according to any one of claims 1 to 4.

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