JP2023077498A - Hot water supply system - Google Patents

Abstract

To provide a hot water supply system advantageous in suppressing electricity charge of a plurality of dwelling houses as a whole, without causing unfair feeling among users of the dwelling houses.SOLUTION: A hot water supply system includes control means for controlling a plurality of storage-type water heaters installed in a plurality of dwelling houses. The control means calculates a heat radiation rate per 24 hours of a hot water storage tank on the basis of a heat storage amount of the hot water storage tank, a hot water supply heat quantity as a heat quantity used in hot water supply, and a heating heat quantity as the heat quantity applied to water by the storage-type water heater, in each of the storage-type water heaters, selects the storage type-water heater in which the heat radiation rate is lower than an average heat radiation rate as an average value of the heat radiation rates of the plurality of storage type water heaters, from the plurality of storage-type water heaters, and changes a time of a heat storage operation of the storage type water heater of a peak shift object.SELECTED DRAWING: Figure 8

Description

The present disclosure relates to hot water supply systems.

A hot water storage type hot water supply system is widely used in which hot water heated by a heating means such as a heat pump is stored in a hot water storage tank, and the hot water extracted from the hot water storage tank is used to supply hot water to a bathtub, a shower, a faucet in a kitchen or a washroom. there is Even in an all-electric type housing complex, there are cases where a heat pump water heater is installed in each dwelling unit. In such collective housing, for the purpose of using cheap electricity rates, a management company contracting with an electric power company receives high voltage power (for example, 6600 volts) collectively and converts it to low voltage power of 100 volts or 200 volts. In some cases, a high-voltage collective power receiving system is adopted in which the power is stepped down and distributed to each house.

Electricity charges for receiving high-voltage power consist of a basic charge determined according to the maximum power consumption and an electric energy charge proportional to the amount of power used. The maximum power consumption is the maximum value of power consumption for each predetermined evaluation period (for example, 30 minutes). Then, if the power consumption in a certain evaluation time period is 100 kW, even if the power consumption in other evaluation time periods is less than 100 kW, it is calculated based on the maximum power consumption of 100 kW for the next year. Base rate applies. Therefore, in order to avoid an increase in electricity charges, it is necessary to keep the maximum power consumption low.

On the other hand, the hot water storage type water heater installed in each house generally performs heat storage operation during the late night hours (for example, from 23:00 to 7:00 the next morning), and stores the heat amount of hot water supply required for one day in the hot water storage tank. is. In addition, power consumption in general households increases during the nighttime after 18:00 during the daytime hours excluding the midnight hours. If the hot water in the hot water storage tank becomes insufficient due to hot water being consumed for filling the bathtub with hot water, keeping warm, or taking a shower during this period, an additional heat storage operation is performed to consume electric power. If such a pattern of heat storage operation is performed similarly in each house, the power consumption of the collective housing increases during a specific time period. For example, as shown in FIG. Power consumption peaks around 5:00 am to 7:00 am just before the end of the hour and around 19:00 to 21:00 at night, which is the second peak time zone.

As a method of suppressing maximum power consumption, it is possible to predict the times of the day when power consumption peaks will occur, and to operate equipment that consumes power during those times during other times of the day. There is a concept of peak shift that suppresses the power consumption of the band. Since the hot water storage type hot water heater can perform heat storage operation at different times, it can be used as a peak shift target device. .

JP 2016-223703 A

In Patent Document 1, in order to perform peak shift, a hot water supply system control device changes the operation time settings of water heaters installed in each house of an apartment complex. The hot water supply system control device collects data on the operation history, hot water usage history, and power consumption history of each house, predicts the power consumption during the peak hours of the next day, and starts the operation of the water heaters in houses where peak shift is possible. Change the time to a time zone with low power consumption (for example, from 2:00 pm to 4:00 pm). For example, if the amount of hot water used in the morning and daytime is less than a predetermined amount, as shown in Fig. 2, part of the late-night operation is shifted to the afternoon when power consumption is low, and the amount of hot water used in the morning and daytime is set as shown in Fig. 2. If it is more than the fixed amount, part or all of the nighttime operation time is moved to the time zone where the power consumption is low as shown in FIG.

In such a hot water supply system, peak shift is performed based on the amount of hot water used in the morning and daytime. In addition, if the operation time is brought forward due to the peak shift as shown in Fig. 3, the time from the completion of heat storage until the hot water is used will be longer than before, so the amount of heat released will increase and the power consumption of the house may increase. have a nature. Therefore, when the frequency of peak shift is biased to a specific house, there is a problem that the user feels unfair compared to other houses.

The present disclosure has been made to solve the above-described problems, and is advantageous in suppressing the electricity charges for the entire multiple houses without causing the user to feel unfair among the houses. An object of the present invention is to provide a hot water supply system that becomes

A hot water supply system according to the present disclosure is a hot water supply system including control means for controlling a plurality of hot water storage type hot water heaters installed in a plurality of homes, wherein the control means controls each hot water storage type hot water heater to store heat in a hot water storage tank. The heat radiation rate of the hot water storage tank per 24 hours is calculated from the amount, the hot water heat amount that is the heat amount used for hot water supply, and the heating heat amount that is the heat amount given to the water by the hot water storage type hot water heater. Among the water heaters, select storage-type water heaters with a lower heat radiation rate than the average heat radiation rate of multiple storage-type water heaters as targets for peak shift, and store heat in storage-type water heaters subject to peak shift. It changes the time of operation.

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a hot water supply system that is advantageous in suppressing electricity charges for a plurality of houses as a whole without causing a user's sense of unfairness among the houses.

It is a figure showing the time change of the power consumption of a house, and the water heater power consumption. FIG. 10 is a diagram showing changes over time in power consumption when a peak shift is performed to change part of the late-night heat storage operation to daytime hours. FIG. 10 is a diagram showing changes over time in power consumption when a peak shift is performed to change heat storage operation at night to daytime. 1 is a configuration diagram of a hot water storage type hot water heater included in the hot water supply system according to Embodiment 1. FIG. 1 is a configuration diagram of a hot water heater control device provided in the hot water storage type hot water heater of Embodiment 1. FIG. 1 is a configuration diagram of a hot water supply system according to Embodiment 1 applied to an apartment house; FIG. 2 is a configuration diagram of a hot water supply system control device provided in the hot water supply system according to Embodiment 1; FIG. 4 is a flowchart showing an example of processing executed by the hot water supply system controller to select a hot water storage type hot water heater to be subjected to peak shift. 4 is a flowchart showing an example of processing executed by the hot water supply system control device to change the time of the heat storage operation of the hot water storage type hot water heater subject to peak shift. FIG. 10 is a diagram showing changes over time in power consumption when a peak shift is performed to bring forward the time of heat storage operation at midnight.

Embodiments will be described below with reference to the drawings. Elements that are common or correspond to each figure are denoted by the same reference numerals, and their explanations are simplified or omitted. In the following description, descriptions such as "water", "hot water", "warm water", and "hot water" basically mean liquid water, and can include cold water to hot water.

Embodiment 1.
FIG. 4 is a configuration diagram of hot water storage type water heater 100 provided in the hot water supply system according to Embodiment 1. As shown in FIG. A hot water supply system according to the present disclosure includes a hot water storage type hot water heater 100 installed in each of a plurality of houses. In the present disclosure, the plurality of residences may be collective housing.

As shown in FIG. 4, the hot water storage type water heater 100 includes a heat pump unit 101 that uses a refrigeration cycle to collect heat from the air to heat water, and a tank unit 102 that has a hot water storage tank 11 that stores heated hot water. , and a remote controller 103 for displaying the operating state and for receiving operating commands and setting value changing operations.

Remote control 103 is an example of a user interface. In the present disclosure, the user interface is not limited to remote control 103 . For example, a smartphone may be configured to be used as a user interface.

The heat pump unit 101 has a compressor 1 , a water-refrigerant heat exchanger 2 , an expansion valve 3 and an air heat exchanger 4 . These devices are annularly connected by pipes and constitute a refrigerant circuit 20 in which the refrigerant is circulated by the compressor 1 . As the refrigerant circulating in the refrigerant circuit 20, it is desirable to use a refrigerant such as carbon dioxide, R32, propane, etc., which is capable of discharging hot water at a high temperature, but the refrigerant is not limited to these refrigerants.

The water-refrigerant heat exchanger 2 exchanges heat between water and a refrigerant, and has an inlet and an outlet for water and an inlet and an outlet for refrigerant. The water that has flowed in through the water inlet is heat-exchanged with the refrigerant and is heated, and flows out from the outlet as hot water with an increased temperature. The air heat exchanger 4 exchanges heat between air and refrigerant. The fan 5 takes in outside air and blows it to the air heat exchanger 4 .

The heat pump unit 101 includes an incoming water temperature sensor 13a that detects the temperature of water flowing into the water-refrigerant heat exchanger 2, an outlet hot water temperature sensor 13b that detects the temperature of heated water flowing out of the water-refrigerant heat exchanger 2, and a heat pump unit. An outside air temperature sensor 13c for detecting the outside air temperature around 101 is provided. The outlet hot water temperature sensor 13b constitutes outlet hot water temperature detection means for detecting the temperature of hot water near the outlet of the water-refrigerant heat exchanger 2 (hereinafter referred to as outlet hot water temperature). The refrigerant circuit 20 also includes a discharge temperature sensor 13d that detects the temperature of the refrigerant discharged from the compressor 1, a suction temperature sensor 13e that detects the temperature of the refrigerant sucked into the compressor 1, and an air heat exchanger 4. and an evaporating temperature sensor 13f for detecting the temperature of the refrigerant at a position serving as an inlet or an intermediate portion of the.

The heat pump control device 14 includes computing means for executing a program by a microprocessor, measuring means for collecting detection data of the temperature sensors 13a to 13f, RAM (Random Access Memory) for storing measurement data and operating state data, and programs. A storage means such as an EEPROM (Electrically Erasable Programmable Read-Only Memory) that stores , a communication means for communicating with the water heater control device 18, the rotational speed of the compressor 1, the opening degree of the expansion valve 3, the fan 5 It includes control means (both not shown) for controlling the rotation speed and the like. Heat pump control device 14 controls the heating capacity of heat pump unit 101 based on the detection values of temperature sensors 13 a to 13 f and input information from water heater control device 18 of tank unit 102 . It should be noted that the water heating means included in the hot water storage type water heater 100 in the present disclosure is not limited to the heat pump unit 101 described above, and may be an electric heater, for example.

The tank unit 102 includes a hot water storage tank 11, a circulation pump 6a, a reheating pump 6b, a switching valve 7, a switching valve 8, a switching valve 9, a hot water supply mixing valve 15a, and a bath mixing valve 15b. and are provided. The circulation pump 6 a circulates water or heated hot water through the heat storage circuit 21 and the reheating circuit 22 to flow into the water-refrigerant heat exchanger 2 or the bath heat exchanger 12 . The circulation pump 6 a forms part of the heat storage circuit 21 or the reheating circuit 22 . The reheating pump 6b sends hot water from a bathtub (not shown) to the bath heat exchanger 12 . The bath heat exchanger 12 uses hot water supplied from the hot water storage tank 11 to heat bath water on the secondary side.

The hot water storage tank 11 stores hot water heated by the heat pump unit 101, and has a high-temperature water outlet 11a located on the upper side of the hot water storage tank 11, a hot water storage port 11b located at the top of the hot water storage tank 11, and hot water storage. A medium-temperature water return port 11c positioned at an intermediate height of the tank 11 and returned to the hot-water storage tank 11 with medium-temperature hot water returned after being used for reheating and low-temperature boiled water positioned at the bottom of the hot-water storage tank 11. A return port 11d, a water intake port 11e located at the bottom of the hot water storage tank 11, and a water supply port 11f located at the lower side of the hot water storage tank 11 are provided.

The switching valve 7 constitutes a switching mechanism for switching the flow path of hot water flowing out of the water-refrigerant heat exchanger 2 to either the switching valve 8 or the low-temperature boiling water return port 11 d of the hot water storage tank 11 . Further, the switching valve 8 constitutes a switching mechanism that causes the inflowing water to flow out to any one of the hot water storage port 11b, the medium-temperature water return port 11c, and the heat exchanger 12 for bath. The switching valve 9 constitutes a switching mechanism for causing the water flowing out from the water intake port 11e of the hot water storage tank 11 or the bath heat exchanger 12 to flow out to the water-refrigerant heat exchanger 2 through the circulation pump 6a.

In the hot water supply mixing unit 15, the high temperature water flowing out from the hot water storage port 11b and passing through the pipe 16g or the high temperature water heated by the heat pump unit 101 and passing through the pipe 16h and the low temperature water from the water supply end 23 are mixed for hot water supply. Mixing is performed by the valve 15a or the bath mixing valve 15b. By adjusting the mixing ratio of the high-temperature water and the low-temperature water, hot water having a set temperature set by the user with the remote controller 103 is generated. Hot water mixed by the hot water supply mixing valve 15a is supplied to a faucet such as a shower or a faucet. Hot water mixed by the bath mixing valve 15b is supplied to the bathtub.

The heat pump unit 101 and the tank unit 102 are connected via a heat pump outgoing pipe 16a, a heat pump return pipe 16k, and electrical wiring (not shown). A water outlet of the water-refrigerant heat exchanger 2 is connected to the switching valve 7 via a heat pump outgoing pipe 16a. The switching valve 7 is connected to the switching valve 8 via a pipe 16b. The switching valve 8 is connected to the high-temperature water outlet 11a through pipes 16c and 16d. Further, the switching valve 8 is connected to the primary side inlet of the bath heat exchanger 12 via the pipes 16c and 16e. A primary side outlet of the bath heat exchanger 12 is connected to the switching valve 9 via a pipe 16f. The switching valve 9 is connected to the intake port 11e through a pipe 16i, and is connected to the suction port of the circulation pump 6a through a pipe 16j.

A discharge port of the circulation pump 6a is connected to the inlet of the water-refrigerant heat exchanger 2 via a pipe 16k, and is connected to the switching valve 7 via a pipe 16l. Further, the switching valve 7 is connected to the low-temperature boiling water return port 11d of the hot water storage tank 11 via a pipe 16m. The switching valve 8 is connected to the hot water storage port 11b of the hot water storage tank 11 through the pipes 16h and 16g, and is connected to the intermediate water return port 11c through the pipe 16o. A water supply port 11f of the hot water storage tank 11 is connected to the water supply end 23 via a pipe 16n.

FIG. 5 is a configuration diagram of water heater control device 18 provided in hot water storage type water heater 100 of Embodiment 1. As shown in FIG. Tank unit 102 incorporates water heater control device 18 shown in FIG. The water heater control device 18 includes a measuring means 181 for measuring detection values of a temperature sensor and a flow rate sensor, which will be described later, and a storage means 182 for storing data measured by the measuring means 181, a control program, and data used as a control determination condition. , computing means 183 for computing control judgment conditions, etc., using data in the storage means 182; driving means 184 for operating valves, pumps, etc. based on the results of the computing means 183; and communication means 185. ing. The communication means 185 communicates with the heat pump control device 14 to collect status monitoring data and transmit control commands for starting and stopping the heat pump unit 101 . Communication means 185 also collects operation command values of remote controller 103 and transmits data stored in storage means 182 to remote controller 103 .

The hot water tank 11 is provided with a plurality of hot water temperature sensors 13g to 13j. The hot water temperature sensors 13g to 13j are installed on the surface of the tank at different height positions, and detect the water temperature in the hot water tank 11 at each installation location. The temperature measured by each of the stored hot water temperature sensors 13g to 13j represents the temperature of the partial water volume of several tens of liters in the range where the sensors are installed. Also, a water supply temperature sensor 13k for detecting the temperature of water to be supplied is provided on the pipe of the water supply end 23 . The water heater control device 18 calculates the amount of heat stored in the hot water storage tank 11 using the following equation (1) using the measured values of the hot water storage temperature sensors 13g to 13j and the water supply temperature sensor 13k, and stores it in the storage means 182. .

Here, Qs is the amount of heat stored in the hot water tank (kJ), ρ is the density of water (kg/m ³ ), Cp is the specific heat of water (kJ/(kg K)), and Vti is the partial water volume of the hot water tank at the temperature sensor position. (m ³ ), Tti is the temperature (° C.) detected by the temperature sensor, and Tc is the water supply temperature (° C.) at the water supply end 23 .

Further, a general hot water supply temperature sensor 13l for detecting the temperature of hot water supplied from the hot water supply mixing valve 15a to the shower, kitchen, etc., a general hot water supply flow rate sensor 17a for detecting the flow rate of the hot water supply, and a hot water supply flow rate sensor 17a for detecting the hot water supply flow rate. A bath hot water supply temperature sensor 13m for detecting temperature and a bath hot water supply flow rate sensor 17b for detecting the flow rate are provided. The water heater control device 18 calculates the general hot water supply heat amount by the following formula (2), calculates the bath hot water heat amount by the following formula (3), calculates the hot water supply heat amount by summing them by the formula (4), and stores the storage means 182 memorize to

Here, Qhw is hot water supply heat amount (kJ), Qbw is bath hot water supply heat amount (kJ), Qsw is general hot water supply heat amount, Fbw is bath hot water supply flow rate (L/min), Fsw is general hot water supply flow rate (L/min), Tbw is Bath hot water supply temperature (° C.), Tsw is general hot water supply temperature (° C.), Δt is measurement cycle (seconds), and t is an index of measurement data for each measurement cycle.

The water heater control device 18 appropriately stores the heat amount of hot water supply obtained by the formula (4) as data obtained by summing up the heat amount for a predetermined time period in order to use it as a judgment condition for control. The aggregation period is one day or a unit time used for determining whether to change the time of the heat storage operation for peak shift, which will be described later. In the latter case, since the hot water supply time period generally varies by about one to two hours depending on the day, a width of several hours is provided, and the amount of hot water supply is aggregated, for example, for three hours.

The heat source circulation flow rate sensor 17 c measures the circulation flow rate between the hot water storage tank 11 and the heat pump unit 101 . In the illustrated example, a heat source circulation flow rate sensor 17c is arranged in the heat pump return pipe 16k near the water-refrigerant heat exchanger 2 . The hot water heater control device 18 can obtain the heating heat amount of the hot water heater during the heat storage operation by the following equation (5). The water heater heating heat amount is the amount of heat given to the water by the heat pump unit 101 .

Here, Qhp is the heating heat amount of the water heater (kJ), Fhp is the circulation flow rate (L/min) between the heat pump unit 101 and the hot water storage tank 11, Two is the outlet hot water temperature of the heat pump unit 101 (°C), and Twi is the heat pump unit. 101 is the incoming water temperature (°C).

Water heater control device 18 and remote control 103 are connected so as to be able to communicate with each other. Although not shown, the remote controller 103 includes a display unit for displaying information such as the operating state of the water heater, an operation unit such as switches operated by the user, a speaker, a microphone, and the like. The water heater control device 18 controls the operation of various valves, pumps, etc., according to operation information from the remote controller 103, and sends information representing the operating state to the remote controller 103 for display and notification.

Next, the operation of the hot water storage type water heater 100 will be described. In the heat storage operation in which hot water is stored in the hot water storage tank 11, the refrigerant circuit 20 and the heat storage circuit 21 are operated, and the low-temperature water flowing out from the water intake port 11e of the hot water storage tank 11 is heated by the refrigerant circuit 20, and the water-refrigerant heat exchanger is operated. 2 flows into the hot water storage tank 11 from the hot water storage opening 11b at the top of the hot water storage tank 11 via the switching valves 7 and 8. In this heat storage operation, heat is stored in the hot water storage tank 11 while maintaining temperature stratification in which the upper portion is high-temperature water and the lower portion is low-temperature water.

Next, hot water temperature control during heat storage operation will be described. In this temperature control, the heat pump control device 14 feedback-controls the rotational speed of the circulation pump 6a so that the temperature of the discharged hot water of the water-refrigerant heat exchanger 2 detected by the discharged hot water temperature sensor 13b becomes equal to a predetermined target discharged hot water temperature. . In the heat storage operation, heat is stored in a state in which the target hot water outlet temperature is set to a predetermined hot water storage target hot water outlet temperature. The target hot water temperature is set based on the operation of remote controller 103 or the like, or is set so as to secure the required amount of heat calculated from the amount of hot water used in the past. The target hot water temperature may be set by any one of the heat pump control device 14, the water heater control device 18, and the remote controller 103. FIG.

The water heater control device 18 determines in advance whether or not the heat storage is completed, for example, the temperature detected by the stored hot water temperature sensor 13j provided at the bottom among the plurality of stored hot water temperature sensors 13g to 13j is set in advance. It is judged whether or not a temperature higher than or equal to the temperature is detected, or whether or not the amount of heat to be heated has reached the target heat storage amount. When the heat storage is completed, the water heater control device 18 issues an operation stop command to the heat pump control device 14 . Upon receiving this command, the heat pump control device 14 stops the heat pump unit 101 and the circulation pump 6a to end the heat storage operation.

The heat storage operation is generally performed in the middle of the night. The hot water supply machine control device 18 plans the start time of the heat storage operation at midnight (for example, 23:00) when the use of hot water supply for the day ends. The water heater control device 18 obtains an average hot water supply heat amount for a predetermined period in the past for the hot water supply heat amount per day obtained by aggregating the hot water supply heat amount calculated using the equation (4). In order to add a margin considering the amount of heat radiation from the hot water storage tank 11 etc. to the average hot water supply heat amount, the water heater control device 18 calculates the heat radiation rate of the hot water storage tank 11 per 24 hours by the following equation (6). demand.

where, Rs: heat dissipation rate, Q _s,0 : past hot water tank heat storage amount (kJ) at 0 o'clock, Q _s,24 : past hot water storage tank heat storage amount (kJ) at 0 o'clock the next day, Vt: tank capacity (m ³ ), Ttave: target boiling temperature, Tcave: average feed water temperature. This heat dissipation rate is a value that indicates the ratio of the amount of heat lost due to heat dissipation from the hot water storage tank 11 and the like to the amount of heat generated by the heat pump unit 101 in the past 24 hours.

The water heater control device 18 uses the heat dissipation rate obtained by the formula (6) to calculate the required amount of heat for the next day by the following formula (7).

Here, Q'hwd: required heat amount (kJ) for the next day, Rsd: average value of heat dissipation rate for a predetermined period, and Qhwd: average value (kJ) of 24-hour hot water supply heat amount for a predetermined period.

The water heater control device 18 sets the operation completion time so that the heat storage is completed at the time when the late-night time zone ends (for example, 7:00 am), and based on the rated capacity of the heat pump unit 101, the following formula (8) Calculate the time required for heat storage operation. The water heater control device 18 determines the operation start time by retroactively counting the time required for the heat storage operation from the operation completion time.

Here, tp is the time (hour) required for the heat storage operation, and Qhps is the rated capacity (kW) of the heat pump unit 101 . For example, if the amount of heat to be heated, that is, the required amount of heat for the next day is 57,600 kJ and the rated capacity of the heat pump is 4 kW, then 57,600÷(4×3600)=4 hours, that is, 3:00 am is set as the operation start time.

When the hot water supply operation is performed by the user, the water supplied from the water supply end 23 is introduced into the water supply port 11f at the bottom of the hot water storage tank 11, and the hot water flows out from the hot water storage port 11b. This operation is performed at a flow rate at which temperature stratification in the hot water storage tank 11 can be maintained. When hot water is supplied from a faucet in a kitchen, shower, or the like, the hot water flowing out from the hot water storage port 11b and the low-temperature water supplied from the water supply end 23 are mixed at a predetermined temperature ratio at the hot water supply mixing valve 15a. Hot water is supplied to the tap. When the bathtub is filled with hot water, the hot water is mixed in the bath mixing valve 15b and supplied to the bathtub.

When reheating the bathtub, the reheating pump 6b is operated to circulate the bathtub water between the bathtub and the bath heat exchanger 12, and at the same time, the hot water taken out from the hot water outlet 11a of the hot water storage tank 11. flows into the bath heat exchanger 12 for heat exchange, thereby heating the bathtub water. The medium-temperature water whose temperature has been lowered by heating the bathtub water in the bath heat exchanger 12 passes through the switching valve 9, the circulation pump 6a, the switching valve 7, and the switching valve 8, and enters the hot-water storage tank 11 from the medium-temperature water return port 11c. flow into

As a result of the use of hot water supply, if the temperature of one of the stored hot water temperature sensors 13g to 13j to be determined falls below a predetermined temperature, the water heater control device 18 runs out of hot water due to subsequent use of hot water supply. Then, additional heat storage operation is performed. The water heater control device 18 ends the additional heat storage operation when the temperature of the sensor to be determined reaches a predetermined temperature. The water heater control device 18 records the additional heat storage amount and the operation time of the heat storage operation for use in power consumption prediction calculation of the hot water supply system, which will be described later.

FIG. 6 is a configuration diagram of a hot water supply system according to Embodiment 1 applied to an apartment house. The housing complex in FIG. 6 includes a plurality of residences such as residences 200a to 200c, and hot water storage type hot water heaters 100a to 100c are installed in each residence. Each of the hot water storage type hot water heaters 100a to 100c is similar to the hot water storage type hot water heater 100 in FIG. The hot water storage type water heaters 100a to 100c are provided with water heater controllers 18a to 18c, respectively. In the following description, when it is not specified which one of the storage-type hot water heaters 100a to 100c, it is described as "hot water storage-type hot water heater 100", and when it is not specified which one of the hot water heater controllers 18a to 18c is described as "hot water heater control device 18". Although the number of houses is three in the example of FIG. 6, it goes without saying that the number of houses may be four or more.

In the following description, the power consumption of the storage-type water heater 100 may be referred to as "water heater power consumption." In addition, the power consumption other than the water heater power consumption in each house may be referred to as "equipment power consumption". Also, the sum of the power consumption of the water heater and the power consumption of the equipment may be referred to as "residential power consumption".

High voltage power of 6600V is received from the electric power company, and is converted to low voltage power of 100V or 200V by the power conversion equipment 41 installed on the premises of the collective housing by the housing management company and delivered to each house.

Hereinafter, the house 200a will be described as a representative, but the same applies to the other houses 200b and 200c.

A house 200a is provided with a distribution board 31a, which is connected to a power line for drawing in power converted to low voltage by a power conversion facility 41, so that electric power is supplied to home appliances such as the hot water heater 100a and devices 32a and 33a. supplied. The devices 32a and 33a are, for example, electric devices such as air conditioners, lighting devices, refrigerators, and televisions.

A power measuring device 51a having a communication function, called a smart meter, is installed on the distribution board 31a. The power measuring device 51a connects a CT (Current Transformer) 35a that measures alternating current to a power line wired in the distribution board 31a. The power measuring device 51a measures the power consumption of the storage-type water heater 100a, that is, the water heater power consumption, and the power consumption of the devices 32a and 33a in the house, that is, the device power consumption. The measured power consumption is converted into kW or power amount kWh data.

The water heater controllers 18a to 18c and the power measuring devices 51a to 51c of each house are connected to the hot water system controller 600 by wireless or wired communication via the routers 34a to 34c. Hot water supply system control device 600 may be connected to routers 34 a - 34 c via network 42 . Hot water supply system control device 600 may be installed, for example, in the premises of an apartment complex and connected to network 42, which is a LAN (Local Area Network) of the apartment complex. Alternatively, hot water supply system control device 600 may be installed in a facility such as a management company outside the premises of the housing complex and connected to network 42, which is the Internet.

Each of the hot water heater control devices 18a to 18c, in addition to the detection values of the temperature sensors 13a to 13m and the detection values of the flow sensors 17a to 17c, for the hot water storage type hot water heaters 100a to 100c, the start time and stop time of the heat storage operation, Data on the amount of heat stored in the hot water storage tank 11 , the heat radiation rate, the amount of heat to be supplied, and the amount of heat to be heated are transmitted to the hot water supply system controller 600 .

Power measuring devices 51a to 51c transmit to hot water supply system control device 600 data of measured values of power consumption of hot water storage type water heaters 100a to 100c and equipment power consumption of houses 200a to 200c, respectively.

FIG. 7 is a configuration diagram of hot water supply system control device 600 provided in the hot water supply system according to Embodiment 1. As shown in FIG. As shown in FIG. 7 , hot water supply system control device 600 includes communication means 601 , storage means 602 , prediction calculation means 603 , priority calculation means 604 , and water heater operating time change means 605 . The communication means 601 connects to the water heater control devices 18a to 18c and the power measuring devices 51a to 51c of each house via a network 42 such as a LAN or the Internet to transmit and receive data. The storage means 602 accumulates and stores the data received from the water heater control devices 18a to 18c and the power measuring devices 51a to 51c of each house and other calculation data used for each hot water heater 100. do. The prediction calculation means 603 uses the data accumulated in the storage means 602 to predict the water heater power consumption and equipment power consumption of each house. The priority calculation means 604 uses the predicted values calculated by the prediction calculation means 603 to calculate the priority scores of the peak shift operation for the hot water storage type water heaters 100a to 100c of each house. The water heater operation time changing means 605 selects the hot water storage type hot water heater 100 to be subjected to the peak shift operation based on the priority score calculated by the priority calculation means 604, and changes the selected hot water storage type hot water heater 100. Along with changing the heat storage operation start time, data of the changed heat storage operation start time and transmission data of the peak shift ON/OFF flag are created.

In the hot water supply system of the present embodiment, the hot water supply system control device 600 and the water heater control device 18 of each residence cooperate to control a plurality of hot water storage type water heaters 100 installed in a plurality of residences. is achieved. Which controller executes which process in the hot water supply system according to the present disclosure is not limited to the description in this specification. For example, the water heater control device 18 may execute the process described herein as being executed by the hot water supply system controller 600, or the hot water supply system control device 18 may perform the process described herein as being executed by the water heater control apparatus 18. It may be performed by the system controller 600 .

Next, the operation of the priority computing means 604 will be described with reference to FIG. FIG. 8 is a flowchart showing an example of processing executed by hot water supply system control device 600 to select hot water storage type hot water heater 100 to be subjected to peak shift. First, in step S001 of FIG. 8, hot water supply system control device 600 determines whether or not the current time is the peak shift plan implementation time. The peak shift plan is executed once a day, for example at 23:00 on the previous day. If the current time is the peak shift plan execution time, the process proceeds to step S002, and the prediction calculation means 603 calculates the predicted value of power consumption for the next day based on the power consumption data collected from the power measuring devices 51a to 51c of each house. calculate. Equipment power consumption includes the power consumption of equipment such as televisions and refrigerators, whose daily usage trends are not affected by the seasons, and the power consumption of equipment, such as air conditioners, whose usage trends vary greatly depending on the season or time of day. is included. For example, when the average value of power consumption for each time period is obtained for a predetermined number of days in the past, the power consumption of air conditioners, which fluctuates greatly depending on the temperature, is smoothed out by calculating the average value. not appropriate as Therefore, the prediction calculation unit 603 uses the following formula (9), which is obtained by correcting for the temperature in addition to the average value for a predetermined period in the past, as a prediction calculation formula for the power consumption of the device.

Here, Ph: predicted value of device power consumption at each time (kW), α: correction coefficient, T: outside temperature (°C), Phave: average value (kW) of device power consumption at each time over a predetermined past period be. As for the outside air temperature, the outside air temperature data measured by the outside air temperature sensor 13c of the heat pump unit 101 is used. Here, the correction coefficient may be determined based on the correlation coefficient obtained by obtaining the linear function of the correlation expression of the data of the outside air temperature and the power consumption of the device in the past. Since the influence of air conditioning power consumption differs between summer when the cooling load is heavy, winter when the heating load is heavy, and interim periods when the air conditioning is hardly used, Equation (9) may be calculated for each season.

On the other hand, in the prediction calculation of the power consumption of the hot water heater, the time at which the heat storage operation occurs may shift from day to day, and a large difference may occur from day to day when comparing for each time. Therefore, we calculated the operation time for one heat storage operation in the late night and daytime hours based on the power consumption data, and set the heat storage operation start time to the time period with high frequency in the past predetermined period in each time. Assuming that the heat storage operation is performed for the set heat storage operation time, the average power consumption during the heat storage operation is assigned to each time. This is the predicted value of the water heater power consumption. For each time, the sum of the predicted value of equipment power consumption and the predicted value of water heater power consumption is used as the predicted value of residential power consumption.

At step S003, hot water supply system control device 600 calculates the degree of divergence as follows. First, hot water supply system control device 600 sums up predicted values of residential power consumption for each house on the next day for each time, and obtains an average predicted value of power consumption, which is the average value of predicted values of residential power consumption at each time for a plurality of houses. . Hot water supply system control device 600 calculates the degree of divergence using the following equation (10). The degree of divergence is a value using the mean square deviation between the predicted average power consumption value and the predicted power consumption value at each time in a predetermined time period. In the present embodiment, data from 00:00 to 23:00, which is one day, is handled as the predetermined time period.

Here, D: degree of divergence, P(t): residential power consumption predicted value (kW) at each time t, Pave: average value (kW) of residential power consumption predicted value per day (24 hours), t1, t2 : time, n: elapsed time from t1 to t2.
In step S003, the degree of divergence is calculated using the house power consumption prediction values for 24 hours from 00:00 to 23:00.

Then, in step S004, hot water supply system control device 600 determines that the next day's peak shift plan is to be carried out when the deviation calculated in step S003 is equal to or greater than a predetermined value. On the other hand, if the degree of deviation is less than the predetermined value, it can be expected that the next day's power consumption in the housing complex will be sufficiently even, and there is no need to change the time of the heat storage operation of the hot water heater 100. Hot water supply system control device 600 determines not to plan the peak shift for the next day.

In step S005, the heat radiation rate data collected from the water heater control devices 18a to 18c of each house are compared, and the priority score for determining the priority to be selected as the peak shift target is obtained by the following equation (11). .

Here, Psi is the priority score of the i-th storage-type water heater 100, Psi′ is the previous priority score of the i-th storage-type water heater 100, β is the correction factor, and Rave is all the storage-type water heaters of each house. An average value of the heat radiation rate of the hot water heater 100, Ri, is the heat radiation rate of the i-th hot water storage type hot water heater 100; The initial value of Psi' is arbitrarily assigned to each hot water storage type water heater 100 in order to determine the initial priority. For example, a storage-type hot water heater 100 has a previous priority score of 5.0, a heat radiation rate Ri of 0.1, an average heat radiation rate Rave of all the storage-type water heaters 100 of 0.15, and a correction coefficient β of 20. , the new priority score is 6.0. Therefore, the storage-type water heater 100 having a heat radiation rate lower than the average heat radiation rate has a high priority score and is likely to be selected as a peak shift target. The priority order is assigned in order from No. 1 in order from the hot water storage type hot water heater 100 with the highest priority score. When the priority scores of a plurality of hot water storage type hot water heaters 100 have the same value, the one with the higher previous priority score is set to a higher priority.

In step S006, hot water supply system control device 600 sequentially selects hot water storage type hot water heaters 100 having a high priority score and a high priority order as peak shift targets, and sets a peak shift ON/OFF flag for target hot water storage type hot water heaters 100. data is set to ON. In step S007, hot water supply system control device 600 changes the time of heat storage operation for hot water storage type hot water heater 100 for which the peak shift ON/OFF flag is ON.

As described above, in the present embodiment, the priority score is calculated based on the heat radiation rate for each storage-type hot water heater 100, and the hot-water storage-type hot water heater 100 to be selected as a peak shift target according to the priority score. determine the priority of As a result, the storage-type hot water heater 100 having a higher heat radiation rate is less likely to be selected as a peak shift target, so that the heat radiation rate of the storage-type water heater 100 can be reliably prevented from increasing due to the peak shift. Therefore, it is possible to reliably prevent a specific house from having a high heat dissipation rate and increasing power consumption compared to other houses. Therefore, it is possible to reduce electricity charges by peak shift in the entire housing complex without causing a user's sense of unfairness among a plurality of houses.

The method of changing the operation time in step S007 will be described with reference to FIGS. 9 and 10. FIG. FIG. 9 is a flowchart showing an example of processing executed by hot water supply system control device 600 to change the time of heat storage operation of storage-type hot water heater 100 subject to peak shift. FIG. 10 is a diagram showing changes over time in power consumption when peak shift is performed to bring forward the time of heat storage operation in the middle of the night.

In step S011 of FIG. 9, it is determined whether or not the amount of hot water supplied during the daytime hours from 7:00 to 17:00 is equal to or less than a predetermined value for the hot water storage type hot water heater 100 subject to peak shift. If the amount of hot water supply heat from 7:00 to 17:00 is not equal to or less than the predetermined value, then in step S012a, as shown in FIG. The start time of the heat storage operation is shifted forward so that the heat storage operation can be completed as soon as possible.

Next, in step S013a, for the hot water storage type water heater 100 subject to peak shift, the predicted value of the water heater power consumption at each time on the next day is recalculated and updated at the new heat storage operation time after the change. Furthermore, the predicted value of residential power consumption for all houses at each time on the next day is recalculated and updated, including the hot water storage type hot water heater 100 subject to peak shift whose heat storage operation time has been changed. As described above, in the present embodiment, after selecting the hot water storage type hot water heater 100 to be peak shifted and changing the time of the heat storage operation, the hot water storage type hot water heater 100 of the next day at the new heat storage operation time after the change. recalculate the predicted value of the power consumption of the water heater for the next day, and recalculate the predicted value of the residential power consumption of all houses at each time on the next day. This makes it possible to predict with high accuracy the house power consumption of all houses at each time on the next day.

Subsequently, in step S014a, the degree of divergence at the heat storage operation start time after the change is recalculated using equation (10) in the same manner as in step S003. It is determined in step S015a whether or not all calculations have been completed for combinations of different operation start times, and if No, the process returns to step S012a and this operation is repeated. For example, the start time of the heat storage operation in the late-night hours is moved forward by 30 minutes or by 1 hour, and the degree of divergence is calculated each time.

In the case of Yes in step S015a, for example, as a result of bringing forward the heat storage operation time, the calculation is completed for all cases until the start time of the heat storage operation reaches 23:00 when the late-night time zone begins, and the process proceeds to step S016. , the time of the heat storage operation when the deviation is the smallest calculated in step S014a is determined as the new time of the heat storage operation after the hot water storage type water heater 100 subject to the peak shift is changed. As described above, in the present embodiment, the degree of deviation is calculated for each combination of a plurality of different times as the time after the heat storage operation of the storage-type hot water heater 100 subject to peak shift is changed, and the time at which the degree of deviation is minimized is calculated. is determined as the time after the heat storage operation of the hot water storage type hot water heater 100 subject to peak shift is changed. This will be more advantageous in leveling the peak power consumption of collective housing.

In step S011, if the amount of hot water supplied by the hot water storage type hot water heater 100 subject to peak shift from 7:00 to 17:00 is equal to or less than a predetermined value, in step S017, the average predicted power consumption value of the collective housing from 7:00 to 17:00 If it is determined in step S018 that the difference from the predicted average power consumption per day is greater than or equal to the predetermined value, this time period is determined to be a time period in which power consumption is relatively high due to air conditioning or the like. In that case, the heat storage operation time in the midnight time zone is not changed from 7:00 to 17:00, and the process proceeds to step S012a to change the heat storage operation time in the midnight time zone.

On the other hand, if the degree of divergence from 7:00 to 17:00 is equal to or less than the predetermined value, the amount of hot water supply heat during the daytime is small and the power consumption of other devices is small, so part of the heat storage operation during the late-night time period is performed during this time period. can be determined to be changeable. In this case, in step S012b, part of the heat storage operation during the late night hours is changed to the daytime hours between 7:00 and 17:00, and the process proceeds to step S013b. In step S013b, for the hot water storage type water heater 100 subject to peak shift, the predicted value of the water heater power consumption at each time on the next day is recalculated and updated at the new heat storage operation time after the change. Furthermore, the predicted value of residential power consumption for all houses at each time on the next day is recalculated and updated, including the hot water storage type hot water heater 100 subject to peak shift whose heat storage operation time has been changed.

Such a change in the time of heat storage operation to the daytime zone is obtained by subtracting the amount of heat obtained by adding the heat dissipation rate to the predicted amount of hot water supply heat in the morning, from the predicted amount of heat required for the day obtained by the formula (7). With the amount of heat as the upper limit, the operating time is changed with a minimum operating time of 30 minutes or 1 hour. Then, in step S014b, the degree of divergence per day is calculated, and the process proceeds to step S015b. In step S015b, it is determined whether or not the combination calculation for changing the operation time to the daytime zone at the upper limit heat quantity or less is completed. For example, the duration of the heat storage operation during the daytime is gradually lengthened, and the calculation of the degree of divergence is repeated. If Yes in step S015b, the process proceeds to step S016. In step S016, the time of the heat storage operation when the degree of deviation is the smallest calculated in step S014b is determined as the new heat storage operation time of the storage-type water heater 100 subject to the peak shift.

Next, in step S019, it is determined whether or not the peak shift determination for the second peak time period after 17:00 has been performed. The same operation is performed by changing the time of the heat storage operation at night after 12:00 to 7:00 to 17:00. If the result of step S019 is No, the change of operating time ends.

The process of step S007 in FIG. 8 is sequentially performed one by one from the hot water storage type hot water heater 100 with the highest priority to be selected as the peak shift target, and in step S008, the degree of divergence of the power consumption of the collective housing per day is less than or equal to a predetermined value. If Yes in step S008, it is determined that the peak shift plan has been completed. If No in step S008, the process returns to step S007 to change the heat storage operation time of the hot water storage type water heater 100 having the next highest priority.

As described above, in the present embodiment, the degree of deviation is calculated based on the time after the heat storage operation of the storage-type water heater 100 subject to peak shift is changed, and if the degree of deviation exceeds a predetermined value, then Another hot water storage type water heater 100 having a higher priority is added to the peak shift target. Then, the degree of deviation is recalculated, and the hot water storage type water heater 100 is added to peak shift targets according to the order of priority until the degree of deviation becomes equal to or less than a predetermined value. This will be more advantageous in leveling the peak power consumption of collective housing.

If Yes in step S008, the process advances to step S009 to update the priority score data of the hot water storage type water heater 100 selected for peak shift to the value with the lowest priority score, and set the peak shift ON/OFF flag. It is set to ON, and the storage unit 602 saves the time of the heat storage operation after the change and the priority score together. Since the next priority score of the storage-type hot water heater 100 that has undergone the peak shift is low, the peak shift operation is not biased toward a specific house.

The communication means 601 transmits the peak shift ON/OFF flag and the time data of the heat storage operation to the hot water heater controller 18 of each hot water storage type hot water heater 100 . When the received data of the peak shift ON/OFF flag is ON, water heater control device 18 updates the time of heat storage operation for the next day with the received data, and from the next day, remote control 103 to inform the user that it is the peak shift implementation day. In this way, the user interface of the storage-type water heater 100 selected for peak shift notifies the implementation of the peak shift, thereby notifying the user in advance that the heat storage operation will be performed at an unusual time. can be done.

As described above, in the present embodiment, among a plurality of hot water storage type hot water heaters 100 in an apartment complex, the hot water storage type hot water heater 100 having a lower heat radiation rate than the average heat radiation rate is selected as a peak shift target. The time for the heat storage operation of the selected hot water storage type water heater 100 is changed. In this way, by allocating the peak shift from the houses with the lowest heat dissipation rate, the influence of the increase in heat dissipation caused by the peak shift is distributed to each house. Power consumption does not increase. Therefore, it is possible to reduce the electricity charges for the entire housing complex by peak shift without causing a user's sense of unfairness among a plurality of houses.

Further, as described above, the hot water supply system controller 600 causes the hot water storage type hot water heater 100, which has been selected as the peak shift target and has performed the heat storage operation at the time after the change, to be the peak shift target at the time of the next peak shift plan. The priority score of the hot water storage type hot water heater 100 is updated so that the selected priority is the lowest. As a result, it is possible to more reliably prevent storage-type hot water heaters 100 that implement peak shift from being biased toward storage-type hot water heaters 100 in specific houses.

1 compressor 2 water refrigerant heat exchanger 3 expansion valve 4 air heat exchanger 5 fan 6a circulation pump 6b reheating pump 7 switching valve 8 switching valve 9 switching valve 11 hot water storage tank 11a hot water outlet 11b hot water storage 11c intermediate hot water return 11d low temperature boiled water return 11e water intake 11f water supply 12 bath heat exchanger 13a inlet water temperature sensor 13b outlet hot water temperature sensor 13c Outside air temperature sensor 13d Discharge temperature sensor 13e Suction temperature sensor 13f Evaporation temperature sensor 13g Storage hot water temperature sensor 13h Storage hot water temperature sensor 13i Storage hot water temperature sensor 13j Storage hot water temperature sensor 13k Water supply temperature sensor 13l General hot water supply temperature sensor 13m bath hot water temperature sensor 14 heat pump control device 15 hot water supply mixing unit 15a hot water supply mixing valve 15b bath mixing valve 16a heat pump outgoing pipe 16b pipe 16c pipe 16d pipe 16e pipe 16f pipe 16g pipe , 16h piping, 16i piping, 16j piping, 16k heat pump return piping, 16l piping, 16m piping, 16n piping, 16o piping, 17a general hot water supply flow rate sensor, 17b bath hot water supply flow rate sensor, 17c heat source circulation flow rate sensor, 18 water heater control device , 20 refrigerant circuit, 21 heat storage circuit, 22 reheating circuit, 23 water supply end, 31a, 31b, 31c distribution board, 32a, 32b, 32c, 33a, 33b, 33c equipment, 41 power conversion equipment, 42 network, 51a, 51b, 51c power measuring device 100 storage hot water heater 100a, 100b, 100c storage hot water heater 101 heat pump unit 102 tank unit 103 remote control 181 measuring means 182 storage means 183 computing means 184 driving means 185 communication means 200a, 200b, 200c house 600 hot water supply system control device 601 communication means 602 storage means 603 prediction calculation means 604 priority calculation means 605 water heater operating time change means

Claims (8)

A hot water supply system comprising control means for controlling a plurality of hot water storage type hot water heaters installed in a plurality of houses,
The control means is
For each of the hot water storage type water heaters, the amount of heat stored in the hot water storage tank, the hot water supply heat amount that is the heat amount used for hot water supply, and the heating heat amount that is the heat amount given to the water by the hot water storage type water heater is calculated. Calculate the heat release rate per 24 hours,
Among the plurality of storage-type hot water heaters, the storage-type water heater having a lower heat radiation rate than an average heat radiation rate of the plurality of storage-type hot water heaters is selected as a peak shift target. death,
A hot water supply system for changing the time of the heat storage operation of the hot water storage type hot water heater subject to the peak shift. The control means calculates a predicted power consumption value for each time of the plurality of houses on the next day, and a difference between the predicted power consumption value for each time and a 24-hour average value of the predicted power consumption values for the plurality of houses. 2. The hot water supply system according to claim 1, wherein a peak shift plan for the next day is performed when the degree of deviation is equal to or greater than a predetermined value. The control means calculates a predicted power consumption value of the plurality of storage-type hot water heaters and a predicted power consumption value of the plurality of houses other than the storage-type hot water heaters for the next day, After selecting the storage-type water heater, the predicted power consumption value of the storage-type water heater for the next day is recalculated at the new heat storage operation time after the change, and the predicted power consumption value for the plurality of houses for the next day is recalculated. The hot water supply system according to claim 1 or 2. The control means calculates a predicted power consumption value for each time of the plurality of houses on the next day, and a difference between the predicted power consumption value for each time and a 24-hour average value of the predicted power consumption values for the plurality of houses. It is possible to calculate the degree of
The control means calculates the degree of deviation based on the time after the change in the heat storage operation of the hot water storage type hot water heater subject to the peak shift, and if the degree of deviation exceeds a predetermined value, the other The hot water supply system according to any one of claims 1 to 3, wherein a hot water storage type hot water heater is added to the peak shift target. The control means calculates a predicted power consumption value for each time of the plurality of houses on the next day, and a difference between the predicted power consumption value for each time and a 24-hour average value of the predicted power consumption values for the plurality of houses. It is possible to calculate the degree of
The control means calculates the degree of deviation for a combination of a plurality of different times as the time after the change in the heat storage operation of the storage-type hot water heater subject to the peak shift, and determines the time when the degree of deviation becomes the smallest. The hot water supply system according to any one of claims 1 to 4, wherein the time is determined as the time after the heat storage operation of the hot water storage type hot water heater subject to the peak shift is changed. The control means calculates a priority score based on the heat radiation rate for each of the storage-type water heaters, and prioritizes the storage-type water heater to be selected as the peak shift target according to the priority score. The hot water supply system according to any one of claims 1 to 5, wherein order is determined. The control means determines the priority order in which the hot water storage type hot water heater that has been selected as the peak shift target and has performed the heat storage operation at the time after the change is selected as the peak shift target in the next peak shift plan. 7. The hot water supply system according to claim 6, wherein the priority score of the hot water storage type hot water heater is updated such that 8. The hot water supply system according to any one of claims 1 to 7, wherein the user interface of the hot water storage type hot water heater selected as the target of the peak shift notifies implementation of the peak shift.

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