JP2010216698A - Heat storage system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat storage system capable of totally improving the energy efficiency of air conditioning equipment or the like including the heat storage system and a heat using device. <P>SOLUTION: In the heat storage system, thermal energy using information is acquired by a thermal energy by means of information acquiring part 20a, COP relevant to an air conditioner is acquired by an air conditioner COP acquiring part 20b, a radiation loss of a heat storage tank is acquired by a radiation loss acquiring part 20c, and COP of a heat source is acquired by a heat source COP acquiring part 20d. A heat storage body temperature control unit 20e controls a temperature of a heat storage body by calculating a target temperature of the heat storage body on the basis of the thermal energy using information, the COP of the air conditioner, the radiation loss, and the heat source COP. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat storage system, and more particularly to a heat storage system for storing thermal energy for cooling and heating.

  2. Description of the Related Art Conventionally, some air conditioning facilities such as buildings and public facilities have a heat storage system. In recent years, interest in heat storage systems has increased from the viewpoint of effective use of energy. In a conventional water heat storage system, heat energy is stored in water, and the stored water is stored in a heat storage tank. For example, cold energy is stored in a water heat storage tank using cheap energy such as nighttime electricity, hot springs and exhaust heat from a bath, and each room of a building or each part of public facilities is stored with heat energy stored in the water heat storage tank. Air conditioning.

  Even in such air conditioning facilities such as buildings and public facilities, the air conditioning and heating of each part of a large facility are performed individually, and are supplied to the air conditioning facilities depending on the season and the usage and usage of the air conditioning facilities. The optimum value of the temperature of water as the heat medium changes. For example, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 8-75220), for cold water supplied to a single refrigerator, the winter or winter and summer seasons when the cooling load is smaller than the summer when the cooling load is large. During the interim period, the chilled water inlet temperature is increased compared to the summer, thereby improving the coefficient of performance of the refrigerator and saving power.

  However, even if the chilled water inlet temperature is changed in the winter or mid-term in response to a decrease in the temperature of the outdoor air wet bulb, in the air conditioning equipment such as large-scale buildings and public facilities, If the efficiency of heat energy storage and storage at the heat source in the heat storage system is not taken into account, the efficiency may be reduced rather than considering the overall energy efficiency of the cooling and heating equipment including the heat storage system, or a sufficient coefficient of performance There is a problem that the improvement and the power saving effect may not be brought out.

  The subject of this invention is providing the heat storage system which can improve energy efficiency altogether, such as an air conditioning installation containing a heat storage system and a heat | fever utilization apparatus.

  A heat storage system according to a first aspect of the present invention is a heat storage system that supplies thermal energy used in a heat utilization device, and supplies the heat energy to the heat utilization device and stores the heat energy by sensible heat, and a heat storage body , A heat source that supplies thermal energy to the heat storage body, heat energy utilization information acquisition means, use side coefficient of performance acquisition means, heat dissipation loss acquisition means, heat source side coefficient of performance acquisition means, and heat storage body Temperature control means.

  The thermal energy usage information acquisition means acquires thermal energy usage information related to the thermal energy usage status in the heat usage device. The use side coefficient of performance acquisition means acquires the use side coefficient of performance of the heat utilization device corresponding to the heat energy utilization information. The heat dissipation loss acquisition means acquires the heat dissipation loss of the heat storage tank. The heat source side coefficient of performance acquisition means acquires the heat source side coefficient of performance of the heat source. The thermal storage temperature control means is acquired by the thermal energy usage information acquired by the thermal energy usage information acquisition means, the usage-side performance coefficient acquired by the performance coefficient acquisition means, the heat dissipation loss acquired by the heat dissipation loss acquisition means, and the heat source side acquisition means The target temperature of the heat storage body is calculated based on the heat source side coefficient of performance, and the temperature of the heat storage body is controlled.

  According to the present invention, the calculation of the target temperature of the heat storage body is performed based on the heat energy utilization information, the utilization-side performance coefficient, the heat dissipation loss, and the heat-source-side performance coefficient. Therefore, the entire energy including the heat utilization device and the heat storage system The target temperature can be calculated in consideration of efficiency.

  The heat storage system according to the second invention is the heat storage system of the first invention, wherein the heat utilization device is an air conditioner. And a thermal energy utilization information acquisition means acquires the thermal energy utilization information called the cooling energy Qcd of an air conditioning apparatus, and the heating energy Qhd of an air conditioning apparatus. The use side coefficient of performance acquisition means acquires a use side coefficient of performance called a coefficient of performance COPvrvc for cooling the air conditioner and a coefficient of performance COPvrvh for heating of the air conditioner. The heat dissipation loss acquisition means acquires the heat dissipation loss Qloss of the heat storage tank. The heat source side coefficient of performance acquisition means acquires the coefficient of performance COPch of the heat source. The heat storage body temperature control means reduces the power consumption W given by the equation W = (Qloss + (1 + 1 / COPvrvc) × Qcd− (1-1 / COPvrvh) × Qhd) / COPch + Qcd / COPvrvc + Qhd / COPvrvh. The target temperature is changed to control the temperature of the heat storage body.

  According to the present invention, the target temperature is set so as to reduce power consumption according to the equation W = (Qloss + (1 + 1 / COPvrvc) × Qcd− (1-1 / COPvrvh) × Qhd) / COPch + Qcd / COPvrvc + Qhd / COPvrvh. Can be set.

  A heat storage system according to a third aspect of the present invention is the heat storage system of the first aspect, wherein the heat utilization device is an air conditioner. And a heat energy utilization information acquisition means acquires heat energy utilization information called the heat exchanger input energy (Qvrvc-Qvrvh) of the air conditioner, the cooling energy Qcd of the air conditioner, and the heating energy Qhd of the air conditioner. The use side coefficient of performance acquisition means acquires a use side coefficient of performance called a coefficient of performance COPvrvc for cooling the air conditioner and a coefficient of performance COPvrvh for heating of the air conditioner. The heat dissipation loss acquisition means acquires the heat dissipation loss Qloss of the heat storage tank. The heat source side coefficient of performance acquisition means acquires the coefficient of performance COPch of the heat source. The heat storage body temperature control means controls the temperature of the heat storage body by changing the target temperature in the direction of decreasing the power consumption W given by the equation W = (Qloss + Qvrvc−Qvrvh) / COPch + Qcd / COPvrvc + Qhd / COPvrvh.

  According to the present invention, the target temperature can be set so as to reduce the power consumption according to the equation W = (Qloss + Qvrvc−Qvrvh) / COPch + Qcd / COPvrvc + Qhd / COPvrvh.

  A heat storage system according to a fourth aspect of the present invention is the heat storage system according to any one of the first to third aspects, wherein the heat storage tank is composed of a plurality of areas. The heat storage body is divided and accommodated in a plurality of areas. The heat storage body temperature control means controls the temperature of a plurality of areas for each area.

  According to the present invention, among the heat storage bodies housed in a plurality of areas of the heat storage tank, the case where the energy loss in the heat storage tank can be reduced by reducing the volume of the heat storage body that controls the target temperature, and the volume of the heat storage body The energy loss can be reduced by increasing the target temperature closer to the ambient temperature, and the energy loss in the heat storage tank can be improved.

  A heat storage system according to a fifth invention is the heat storage system according to any one of the first to fourth inventions, wherein the heat storage body is water.

  According to the present invention, water that is stable and easy to handle and has a large specific heat is used as a heat accumulator, so that the target temperature can be easily calculated and controlled.

  In the heat storage system according to the first invention, the target temperature can be calculated in consideration of the overall energy efficiency including the heat utilization device and the heat storage system, and the target temperature of the heat storage body can be set so as to improve the overall energy efficiency.

  In the heat storage system according to the second aspect of the invention, the target temperature can be set so that the overall power consumption including the heat utilization device and the heat storage system is reduced.

  In the heat storage system according to the third aspect of the invention, the target temperature can be set so that the overall power consumption including the heat utilization device and the heat storage system is reduced.

  In the heat storage system according to the fourth aspect of the invention, improvement in energy loss in the heat storage tank can be linked to improvement in overall energy efficiency.

  In the heat storage system according to the fifth aspect of the present invention, a target temperature can be easily set and a system that is easy to handle can be provided.

Schematic for demonstrating the structure of the thermal storage system of 1st Embodiment. The block diagram for demonstrating the structure of the thermal storage system of this invention. The flowchart for demonstrating target temperature control in the thermal storage system of 1st Embodiment. Schematic for demonstrating the structure of the thermal storage system of 2nd Embodiment. (A) The schematic diagram which shows one state of the thermal storage system of 2nd Embodiment. (B) The schematic diagram which shows the other state of the thermal storage system of 2nd Embodiment. (C) The schematic diagram which shows the other state of the thermal storage system of 2nd Embodiment. (D) The schematic diagram which shows the other state of the thermal storage system of 2nd Embodiment. Schematic for demonstrating the structure of the thermal storage system of 3rd Embodiment.

[First Embodiment]
The heat storage system by 1st Embodiment is demonstrated using FIG. FIG. 1 shows a heat storage system 1 and an air conditioner 2 as a heat utilization device that receives supply of thermal energy from the heat storage system 1. The air conditioner 2 is a building multi-type air conditioner composed of a large number of outdoor units 3a, ... 3b and a large number of indoor units 4aa, ... 4ab, 4ba, ... 4bb. For example, a plurality of indoor units 4aa,... 4ab are connected to one outdoor unit 3a to constitute one system. Here, in order to simplify the description, it is assumed that heating or cooling is performed in one system. That is, all the indoor units 4aa,..., 4ab are in a state of being heated or all being cooled. In general, in the indoor units 4aa,... 4ab, 4ba,... 4bb, in addition to heating and cooling, other air conditioning such as dehumidification and ventilation is performed, but since the influence on heat energy exchange is extremely small, Description of air conditioning other than cooling is omitted.

<Hydrothermal medium circulation>
The heat storage system 1 includes a heat storage tank 6 for housing a water heat medium 5 that is a heat storage body and also a heat medium, and a heat source 7 for supplying heat energy to the water heat medium 5 of the heat storage tank 6. . Further, in order to circulate the water heat medium 5 from the heat storage tank 6 to the air conditioner 2, the heat storage system 1 includes pipes 10a, 10b, 13a,... 13b, a forward header 8 and a return header 9, and a cooling / heating switching valve 11a, 11b, 11c, 11d, a number of on-off valves 12a,... 12b, and a pump 14. The heat storage tank 6 is divided into a low temperature side 6a in which a relatively low temperature water heat medium 5 is stored and a high temperature side 6b in which a relatively high temperature water heat medium 5 is stored. The hydrothermal medium 5 goes back and forth between the low temperature side 6a and the high temperature side 6b. Therefore, the hydrothermal medium 5 circulated from the low temperature side 6a or the high temperature side 6b of the heat storage tank 6 to the high temperature side 6b or the low temperature side 6a via the forward header 8, the air conditioner 2 and the return header 9 by the pump 14. In the heat storage tank 6, it moves from one of the low temperature side 6a and the high temperature side 6b to the other.

  When the cooling load in the air conditioner 2 is larger than the heating load and can be regarded as a cooling load as a whole, the cold hydrothermal medium 5 is taken in from the pipe 10a on the low temperature side 6a, and the cold hydrothermal medium 5 is taken into the air conditioner 2 The warm hydrothermal medium 5 is returned from the pipe 10b to the high temperature side 6b. In order to take water from the low temperature side 6a and drain it to the high temperature side 6b, the cooling / heating switching valves 11a, 11d are closed and the cooling / heating switching valves 11b, 11c are opened. On the contrary, when the heating load is larger than the cooling load in the air conditioner 2 and can be regarded as the heating load as a whole, the hot water heating medium 5 is taken in from the high temperature side 6b through the pipe 10b, and the low temperature side 6a is connected through the pipe 10a. In order to drain the cold hydrothermal medium 5, the cooling / heating switching valves 11a, 11d are opened and the cooling / heating switching valves 11b, 11c are closed.

  The hydrothermal medium 5 sent to the forward header 8 by the pipe 10a or the pipe 10b is distributed to the pipes 13a,... 13b by the forward header 8, and individually sent to the outdoor units 3a,. At this time, the hydrothermal medium 5 is not sent to the outdoor units 3a,... 3b that are not in operation, and the open / close valves 12a,. The water refrigerant 5 having finished heat exchange in the outdoor units 3a,... 3b is returned from the pipes 13a,... 13b, collected by the header 9, and sent to the heat storage tank 6 through the pipes 10b or 10a. At this time, the flow rate of the hydrothermal medium 5 sent to the outdoor units 3a, ... 3b by the pump 14 is individually adjusted.

  The heat source 7 includes a plurality of chillers 7a, ... 7b. In order to circulate the water heating medium 5 to the heat source 7, the heat storage system 1 includes a cooling / heating switching valve 15a, 15b, 15c, 15d, a forward header 16 and a return header 17, a pump 18, and pipes 10c, 10d, 19a,. 19b.

  When the air conditioning apparatus 2 has a large cooling load, the hot water heat medium 5 is taken in from the high temperature side 6b through the pipe 10d, and the hot water heat medium 5 is circulated to the heat source 7 through the pipes 19a, ... 19b to the low temperature side 6a. In order to return the cold hydrothermal medium 5 through the pipe 10c, the cooling / heating switching valves 15a, 15d are closed and the cooling / heating switching valves 15b, 15c are opened. On the other hand, when the heating load is large, the cold hydrothermal medium 5 is taken in from the low temperature side 6a, the cold hydrothermal medium 5 is circulated to the heat source 7, and the warm hydrothermal medium 5 is returned to the high temperature side 6b. The valves 15a and 15d are opened and the cooling / heating switching valves 15b and 15c are closed.

  The chillers 7a,... 7b are used in combination so as to be most efficient according to the required capacity. Therefore, which of the chillers 7 a,.

<Measurement equipment for control>
Next, the control in the heat storage system 1 is demonstrated using FIG.1, FIG.2 and FIG.3. Here, in order to make the explanation easy to understand, the scope of the explanation regarding the control is focused on the control concerning the target temperature. FIG. 2 is a block diagram for explaining the control of the heat storage system 1 shown in FIG. The heat storage system 1 includes a number of temperature sensors, a number of power meters, and a number of flow meters in addition to the control unit 20 for performing control.

  As shown in FIG. 2, the temperature sensor connected to the control unit 20 includes a utilization device heat medium inlet temperature sensor 22, a utilization device heat medium outlet temperature sensor 23, a forward header heat medium temperature sensor 24, and a return header heat medium temperature. There are a sensor 25, a heat storage tank temperature sensor 26, an ambient temperature sensor 27, a heat source heat medium inlet temperature sensor 28, and a heat source heat medium outlet temperature sensor 29. In the utilization device heat medium inlet temperature sensor 23, outdoor unit inlet temperature sensors 22a, ... for measuring the temperature of the water heat medium 5 flowing into the outdoor units 3a, ... 3b for heat exchange in the outdoor units 3a, ... 3b. 22b is included. The utilization device heat medium outlet temperature sensor 23 includes outdoor unit outlet temperature sensors 23a, ... 23b for measuring the temperature of the water heat medium 5 flowing out of the outdoor units 3a, ... 3b after heat exchange in the outdoor units 3a, ... 3b. included. The forward header heat medium temperature sensor 24 is provided upstream of the forward header 8 and measures the temperature of the water heat medium 5 flowing into the forward header 8. The return header heat medium temperature sensor 25 is provided downstream of the return header 9 and measures the temperature of the water heat medium 5 flowing out from the return header 9.

  The heat storage tank temperature sensor 26 includes a low temperature side temperature sensor 26a for measuring the temperature of the water heating medium 5 (heat storage body) at the inlet of the pipe 10a, and a pipe of the high temperature side 6b. A high temperature side temperature sensor 23b for measuring the temperature of the hydrothermal medium 5 at the inlet 10b is included. The ambient temperature sensor 27 includes a temperature sensor 27 a that measures the temperature of the atmosphere around the outdoor units 3 a,... 3 b, a temperature sensor 27 b that measures the temperature of the atmosphere around the heat storage tank 6, and the atmosphere around the heat source 7. A temperature sensor 27c for measuring temperature is included.

  The heat source heat medium inlet temperature sensor 28 includes chiller inlet temperature sensors 28a,... 28b that measure the temperature of the water heat medium 5 flowing into the chillers 7a,. The heat source heat medium outlet temperature sensor 29 includes chiller outlet temperature sensors 29a,... 29b that receive the supply of heat energy from the heat source 7 and measure the temperature of the water heat medium 5 that flows out of the chillers 7a,. 2 includes system-specific power meters 31a,... 31b. The system-specific power meters 31a, ... 31b measure the amount of power of the system connected to the outdoor units 3a, ... 3b.

  As shown in FIG. 2, the flow meter connected to the control unit 20 includes an outdoor unit flow meter 32a,... 32b, a header heat medium flow meter 33, and a heat source heat medium flow rate. A chiller flow meter 34a, ... 34b, which is a total of 34, is included. The outdoor unit flow meters 32a, ... 32b measure the flow rate of the hydrothermal medium 5 flowing through the outdoor units 3a, ... 3b, respectively, for heat exchange. The chiller flow meters 34a, ... 34b measure the flow rate of the hydrothermal medium 5 flowing through the chillers 7a, ... 7b, respectively, for heat exchange.

<Control unit>
The control unit 20 sets a target temperature based on the information received from the measurement device as described above, and controls the temperature of the heat storage tank 6. For control of the target temperature, the control unit 20 includes a heat energy utilization information acquisition unit 20a, an air conditioner COP acquisition unit 20b, a heat dissipation loss acquisition unit 20c, a heat source COP acquisition unit 20d, and a heat storage body temperature control unit. 20e, an energy use related information storage unit 20f, an air conditioner COP storage unit 20g, a heat storage tank heat radiation characteristic storage unit 20h, and a heat source COP storage unit 20i.

(1) Acquisition of thermal energy usage information The thermal energy usage information acquisition unit 20a acquires thermal energy usage information regarding the thermal energy usage status in the air conditioner 2 (heat usage device). The acquired heat energy utilization status includes the cooling energy Qcd [kW], the heating energy Qhd [kW], the heat exchanger input energy (Qvrvc−Qvrvh) [kW], and the like of the air conditioner 2. Here, Qvrvc is the heat exchanger input energy of the system that is performing cooling, and Qvrvh is the heat exchanger input energy of the system that is performing heating. (Qvrvc−Qvrvh) represents a case where the cooling load is large, and (Qvrvh−Qvrvc) is obtained when the heating load is large. The thermal energy utilization information acquisition unit 20a acquires these pieces of information directly or indirectly. There are various methods for acquiring the cooling energy Qcd and the heating energy Qhd of the air conditioner 2. For example, the cooling energy Qcd and the heating energy Qhd acquired by the heat energy utilization information acquisition unit 20a are supplied to each outdoor unit 3a,. It can be obtained from thermal energy given from the heat medium 5. Therefore, the heat energy utilization information acquisition unit 20a includes the outdoor unit inlet temperature sensors 22a, ... 22b of the utilization device heat medium inlet temperature sensor 22, and the outdoor unit outlet temperature sensors 23a of the utilization device heat medium outlet temperature sensor 23, ... the temperature of the hydrothermal medium 5 measured by 23b is input. The heat energy utilization information acquisition unit 20a receives the flow rate of the hydrothermal medium 5 flowing through the outdoor units 3a, ... 3b measured by the outdoor unit flow meters 32a, ... 32b of the utilization device heat medium flow meter 32. Then, the heat energy utilization information acquisition unit 20a obtains the amount of heat received by the outdoor units 3a, ... from the temperature difference and flow rate of the hydrothermal medium 5 before and after heat exchange in the outdoor units 3a, ... 3b. Further, the power consumption of each system is obtained from the system-specific power meters 31a,.

  Most of the amount of heat received by these outdoor units 3a,... 3b is given to indoor air from the indoor units 4aa,... 4ab, 4ba,. At this time, a part of the heat escapes due to heat dissipation of the heat exchanger or piping, so the magnitude of the loss differs for each system, but the thermal energy input to the outdoor units 3a, ... 3b of each system and the indoor units 4aa, ... 4ab, 4ba,... 4bb can be measured in advance and stored in the energy use related information storage unit 20f. The thermal energy utilization information acquisition unit 20a includes outdoor unit inlet temperature sensors 22a, ... 22b, outdoor unit outlet temperature sensors 23a, ... 23b, outdoor unit flow meters 32a, ... 32b, and system-specific watt meters 31a, ... 31b. Based on the measurement result, the cooling system is divided into the cooling system and the heating system, and the cooling energy Qcd and the heating energy are obtained by subtracting the power consumption from the thermal energy received by the outdoor units 3a, ... 3b, respectively. Qhd can be calculated.

  In addition, when heat dissipation in a heat exchanger or piping differs depending on the outside air temperature, correction can be made based on the measured value of the temperature sensor 27a that measures the outside air temperature. Also in that case, the relationship between the thermal energy input to the outdoor units 3a,... 3b of each system and the thermal energy output from the indoor units 4aa,... 4ab, 4ba,. And the change relationship is stored in the energy use related information storage unit 20f. Such correction may be performed using other parameters.

  Further, as a simple method for acquiring the cooling energy Qcd and the heating energy Qhd, the power consumption of the outdoor units 22a,... 22b measured by the system-specific watt meters 31a,. It can also be obtained by obtaining the temperature of the outside air of the outdoor units 3a, ... 3b. By measuring the relationship between the outdoor air temperature, power consumption, and cooling energy Qcd of the outdoor units 3a,... 3b when one system is performing cooling in advance, the data is obtained in advance to obtain the outdoor air temperature and power consumption. If the cooling energy Qcd is associated, the cooling energy Qcd can be specified if the outside air temperature and the power consumption are known. In this case, in order to specify the cooling energy Qcd, data indicating the relationship between the outside air temperature, the power consumption, and the cooling energy Qcd is stored in the energy usage related information storage unit 20f, and the thermal energy usage information acquisition unit 20a is outdoors. Of the units 3a,... 3b, although cooling is performed, each outdoor unit 3a,... 3b is stored from the energy use related information storage unit 20f on the basis of the measurement results of the wattmeters 31a,. Acquire cooling energy Qcd. Similarly, the heat energy utilization information acquisition unit 20a is related to energy utilization based on the measurement results of the wattmeters 31a, 31b for each system and the measurement results of the temperature sensor 27a of the outdoor units 3a,. Heating energy Qhd is acquired from the information storage unit 20f. Also in this case, the energy use related information storage unit 20f stores data indicating the relationship between the outside air temperature, the power consumption, and the heating energy Qhd.

  Next, the thermal energy utilization information acquisition unit 20a measures the heat exchanger input energy (Qvrvc−Qvrvh) [kW] by the forward header heat medium temperature sensor 24 and the return header heat medium temperature sensor. It is acquired based on the temperature of the hydrothermal medium 5 measured at 25 and the flow rate of the hydrothermal medium 5 measured by the header heat medium flow meter 33. It relates to the total amount of energy given to the air conditioner 2 from the temperature difference and flow rate between the water heat medium 5 flowing into the forward header 8 and the water heat medium 5 flowing out from the return header 9, that is, the heat exchanger input energy (Qvrvc−Qvrvh). The amount of heat is calculated. Since heat is released into the atmosphere through the pipes 13a,... 13b and the like, a loss occurs, so the value obtained from the amount of heat related to the heat exchanger input energy (Qvrvc−Qvrvh) includes an error. The error can be corrected by measuring or obtaining data by simulation or the like. Thus, the relationship between the amount of heat known from the measurement and the heat exchanger input energy (Qvrvc-Qvrvh) is described in the energy use related information storage unit 20f. Therefore, the heat energy use information acquisition unit 20a is configured to transfer the heat exchanger from the energy use related information storage unit 20f based on the measurement results of the forward header heat medium temperature sensor 24, the return header heat medium temperature sensor 25, and the header heat medium flow meter 33. Input energy (Qvrvc−Qvrvh) can be acquired. Further, when the heat exchanger input energy (Qvrvc−Qvrvh) varies depending on the outside air temperature or the like, the obtained heat exchanger input energy (Qvrvc−Qvrvh) is corrected by the outside air temperature measured by the temperature sensor 27a. You can also.

  Qvrvc is (1 + 1 / COPvrvc) × Qcd from the cooling energy Qcd and the COPvrvc of the air conditioner 2 described later, and Qvrvh is calculated from the heating energy Qhd and the COPvrvh of the air conditioner 2 described later as (1-1 / COPvrvh) × Qhd can also be calculated. The heat energy utilization information acquisition unit 20a can also obtain heat exchanger input energy (Qvrvc−Qvrvh) [kW] by such calculation.

(2) Acquisition of COP of air conditioner The air conditioner COP acquisition unit 20b acquires the coefficient of performance (COPvrvc, COPvrvh) of the air conditioner 2 directly or indirectly, but COPvrvc, COPvrvh of the air conditioner 2 Is obtained as a function of the target temperature Tt. There are various methods for acquiring COPvrvc (Tt) and COPvrvh (Tt). For example, the power consumption of the outdoor units 3a,... 3b measured by the system-specific power meters 31a,. ,... 22b can be obtained by obtaining the heat medium inlet temperature (temperature of the water heat medium 5) of the outdoor units 3a,. The heat medium is obtained in advance by measuring the relationship between the heat medium inlet temperature, power consumption, COPvrvc and COPvrvh of the outdoor units 3a,... 3b when one system performs cooling or heating. If COPvrvc or COPvrvh is associated with the inlet temperature and power consumption, COPvrvc or COPvrvh can be specified as a function of the target temperature Tt if the heat medium inlet temperature and power consumption are known. Here, data indicating the relationship among the heat medium inlet temperature, power consumption, COPvrvc, and COPvrvh is stored in the air conditioner COP storage unit 20g, and the air conditioner COP acquisition unit 20b includes the outdoor units 3a, ... 3b. Although the cooling is performed, COPvrvc and COPvrvh of each of the outdoor units 3a,... 3b are obtained from the air conditioner COP storage unit 20g based on the measurement results of the system-specific watt meters 31a,. get.

  Moreover, in the air conditioner COP acquisition part 20b, as a simple method for acquiring COPvrvc and COPvrvh of the air conditioner 2, one of the outdoor units 3a, ... 3b used for cooling and used for heating. It is also possible to individually determine COPvrvc and COPvrvh of the system to which each outdoor unit 3a, ... 3b belongs from the heat medium inlet temperature. It can be determined whether each system is used for cooling or heating by comparing which one of the outdoor unit inlet temperature sensors 22a,... 22b and the outdoor unit outlet temperature sensors 23a,. If the air conditioner COP storage unit 20g stores data measured in advance so that the relationship between the heat medium inlet temperature and the COPvrvc and COPvrvh of each system has a one-to-one correspondence, the air conditioner COP acquisition unit 20b is based on the measurement results of the outdoor unit inlet temperature sensors 22a, ... 22b of the utilization device heat medium inlet temperature sensor 22 and the outdoor unit outlet temperature sensors 23a, ... 23b of the utilization device heat medium outlet temperature sensor 23. The COPvrvc and COPvrvh of the system to which the outdoor units 3a,... 3b belong can be acquired from the air conditioner COP storage unit 20g.

  Further, in the acquisition of COP in the air conditioner COP acquisition unit 20b, the COP acquired by the air conditioner COP acquisition unit 20b as described above is used as the heat energy given to the outdoor units 3a,. It can also be corrected in consideration of Therefore, the air conditioner COP acquisition unit 20b includes the outdoor unit inlet temperature sensors 22a,... 22b and the outdoor unit outlet temperature sensors 23a,. The flow rate of the hydrothermal medium 5 flowing in the outdoor units 3a, ... 3b measured by the flow meters 32a, ... 32b is input. The air conditioner COP acquisition unit 20b obtains the amounts of heat received by the outdoor units 3a, ... from the temperature difference and the flow rate of the water heating medium 5 before and after heat exchange in the outdoor units 3a, ... 3b.

(3) Acquisition of heat dissipation loss The heat dissipation loss acquisition unit 20c acquires the heat dissipation loss Qloss of the heat storage tank 6 directly or indirectly. The heat dissipation loss Qloss is a function of the target temperature Tt, the ambient temperature Ta, and the heat insulation coefficient ρ. Since the ambient temperature Ta and the heat insulation coefficient ρ are determined by measurement, the heat dissipation loss acquisition unit 20c acquires them as a function of the target temperature Tt. Is done. There are various methods for acquiring the heat dissipation loss Qloss. For example, the heat dissipation loss Qloss can be acquired by measuring the ambient temperature Ta with the temperature sensor 27b. In this case, by changing the target temperature Tt in advance and measuring the heat dissipation loss Qloss corresponding to the ambient temperature Ta to obtain data, there is no change in the heat insulation coefficient ρ unless the aspect of the heat storage tank 6 is changed. A heat dissipation loss Qloss is specified as a function of the target temperature Tt. Here, for each target temperature Tt, the heat dissipation loss Qloss corresponding to the ambient temperature Ta is stored in the heat storage tank heat dissipation characteristic storage unit 20h, and the heat dissipation loss acquisition unit 20c calculates the heat dissipation loss Qloss based on the measurement result of the temperature sensor 27b. Obtained as a function of target temperature Tt.

  In addition, since the heat storage tank 6 is installed on the concrete foundation with a concrete water tank, for example, the ambient temperature Ta is not determined only by the atmospheric temperature of the heat storage tank 6, and the temperature of the concrete foundation needs to be measured. There can be. However, if the basic temperature is a function of the ambient temperature, the heat dissipation loss Qloss can be obtained with a relatively small error even at the ambient temperature Ta alone. Of course, the ambient temperature Ta may include not only the ambient temperature but also other temperature-related parameters such as the foundation. In this case, a measuring device for measuring these parameters can be added.

  Further, depending on the value of the ambient temperature Ta, the heat dissipation loss Qloss may be zero, or conversely, the heat storage body may absorb heat energy from the surroundings. For example, the ambient temperature Ta is lower than the target temperature Tt when the cooling load is large, or the ambient temperature Ta is higher than the target temperature Tt when the heating load is large. At this time, the target temperature Tt can be derived by changing the sign of the heat dissipation loss Qloss. That is, in such a case, calculation is performed as a gain, not as a loss of energy.

(4) Acquisition of COP of heat source The heat source COP acquisition unit 20d acquires the coefficient of performance (COPchc, COPchh) of the heat source 7 directly or indirectly. COPchc and COPchh of these heat sources 7 are acquired as a function of the target temperature Tt. There are various methods for obtaining COPchc (Tt) and COPchh (Tt). For example, the power consumption of the chillers 7a,..., 7b measured by the wattmeters 35a,. ... directly obtained by obtaining the temperature of the hydrothermal medium 5 measured by 28b and the chiller outlet temperature sensors 29a, ... 29b and the flow rate measured by the chiller flow meters 34a, ... 34b of the heat source heat medium flow meter 34. it can.

  Further, as a simple method, for example, it is obtained by obtaining the power consumption of the chillers 7a,... 7b measured by the watt meters 35a,... 35b of the heat source wattmeter 35 and the temperature of the outside air measured by the temperature sensor 27c. it can. In this case, each chiller 7a, ... 7b measures the relationship between the outside air temperature, power consumption, flow rate, COPchc and COPchh of the chillers 7a, ... 7b when the water heating medium 5 is cooled or heated in advance. If COPchc or COPchh is associated with the outside air temperature, power consumption, and flow rate in advance by obtaining the data, COPchc or COPchh is specified as a function of the target temperature Tt if the outside air temperature, power consumption, and flow rate are known. Therefore, data indicating the relationship among the outside air temperature, power consumption, flow rate, COPchc, COPchh is stored in the heat source COP storage unit 20i, and the heat source COP acquisition unit 20d performs cooling or heating among the chillers 7a,. However, the COPchc and COPchh of the chillers 7a,... 7b are acquired from the heat source COP storage unit 20i based on the measurement results of the wattmeters 35a,.

  As described above, the chillers 7a,..., 7b are different models, and the respective capacities may not necessarily be the same. Therefore, the wattmeters 35a,. Ascertained from the measurement results of the flow meter, if the chillers 7a,... 7b are the same model and have the same settings, the power meters 35a,... 35b and the chiller flow meters 34a,. Measurement of is not necessary. If the target temperature Tt is determined, the thermal energy supplied by the chillers 7a,... 7b and the flow rate of the water heating medium 5 are determined. Therefore, there is no need for measurement with the wattmeters 35a,... 35b and the chiller flow meters 34a,. In such cases, the heat source COP acquisition unit 20d acquires the relationship between the target temperature Tt and COPchc, COPchh from the heat source COP storage unit 20i.

  In the heat storage body temperature control unit 20e, the air conditioner 2 and the heat storage system 1 using the parameters acquired by the heat energy utilization information acquisition unit 20a, the air conditioner COP acquisition unit 20b, the heat dissipation loss acquisition unit 20c, and the heat source COP acquisition unit 20d. And the target temperature Tt is calculated so that the power consumption W is minimized. The control unit 20 controls the chillers 7a,... 7b, the pump 18 and the like of the heat source 7 so as to reach the target temperature Tt.

(4) Other Controls In addition to the above control, the control unit 20 controls the valve group 37 and the pump group 38 in order to operate the heat storage system 1. The valve group 37 includes the already described cooling / heating switching valves 11a, 11b, 11c, 11d, 15a, 15b, 15c, 15d and the opening / closing valves 12a,. The pump group 38 includes the pump 14 and the pump 18. Adjustment of the flow rate of the hydrothermal medium 5 sent to the outdoor units 3a,... 3b by the pump 14 is performed by the control unit 20 so that a necessary heat capacity can be supplied according to the cooling load or heating load of each system. . Further, the controller 20 adjusts the on / off of the supply of the hydrothermal medium 5 to the chillers 7a,.

<Target temperature control>
Next, control of the target temperature by the control unit will be described with reference to FIG. In the following description, in order to make the explanation easy to understand, the air conditioning apparatus 2 includes a cooling system and a heating system, but the cooling load is larger than the heating load as a whole. Explained as an example.

  As the target temperature Tt of the water heating medium 5 stored in the heat storage tank 6, a temporary target temperature Tt0 is set based on, for example, the results of the previous day (step ST1). In the following description, data relating to the target temperature is represented with a suffix 0. Since the heat storage system 1 must be operated until the optimum target temperature is calculated, it is operated at the temporary target temperature Tt0. At this time, the result of the previous day is usually used because the change in the environment and the usage situation is less when the time is closer. For example, when the usage situation changes every day of the week, the previous week's achievement is used. You can also. Thus, the situation where the air conditioner 2 is installed is taken into consideration when setting the temporary target temperature Tt0.

  When the temporary target temperature Tt0 is set, the heat storage body temperature control unit 20e determines a plurality of candidate temperatures Tt1, ... Ttn in the vicinity of the temporary target temperature Tt0. In the following description, the candidate temperatures are represented by subscripts 1 to n. If the candidate temperature is determined under a predetermined condition, for example, within a range of 2 degrees before and after the temporary target temperature Tt0, if Tt0 = 21 ° C, 19 ° C, 20 ° C, 22 ° C, and 23 ° C are set as candidate temperatures.

  The thermal energy utilization information about the target temperature Tt0 and the candidate temperatures Tt1,... Ttn, the COP of the air conditioner 2, the heat radiation loss, and the COP of the chillers 7a,. As the heat energy use information acquired by the heat energy use information acquisition unit 20a, since the cooling load is larger, the heat exchange input energy (Qvrvc0-Qvrvh0) at the target temperature Tt0 and the air conditioner 2 at the target temperature Tt0. Cooling energy Qcd0 and heating energy Qhd0. The air conditioner COP acquisition unit 20b uses the cooling coefficient of performance COPvrvc0 for the entire system that is performing the cooling and the heating coefficient of performance COPvrvh0 for the entire system that is performing the heating for the air conditioner 2. The heat dissipation loss acquisition unit 20c acquires the heat dissipation loss Qloss0 of the heat storage tank 6 at the temporary target temperature Tt0. Further, since the cooling load is large, the heat source COP acquisition unit 20d acquires the coefficient of performance COPchc0 of the heat source at the temporary target temperature Tt0d.

  Similarly, the candidate temperatures Tt1,... Ttn are also acquired. For example, if the candidate temperature Ttn, the heat exchange input energy (Qvrvcn-Qvrvhn), the cooling energy Qcdn and the heating energy Qhdn of the air conditioner 2 at the target temperature Ttn, A cooling performance coefficient COPvrvcn, a heating performance coefficient COPvrvhn, a heat dissipation loss Qlossn, and a heat source performance coefficient COPchcn are acquired.

  When the parameters necessary for calculating the power consumption W0, W1,... Wn at the temporary target temperature Tt0 and the candidate temperatures Tt1,... Ttn are acquired in step ST2, the heat storage body temperature control unit 20e acquires the temporary target temperature Tt0. The power consumption W0, W1,... Wn is obtained (step ST3). The power consumption W0 is obtained by the following equation (1), and the candidate temperatures Tt1,... Ttn are obtained by the following equation (2) when the candidate temperature Ttn is taken as an example.

  W0 = (Qloss0 + Qvrvc0−Qvrvh0) / COPchc0 + Qcd0 / COPvrvc0 + Qhd0 / COPvrvh0 (1)

  Wn = (Qlossn + Qvrvcn−Qvrvhn) / COPchcn + Qcdn / COPvrvcn + Qhdn / COPvrvhn (2)

  In the next step ST4, the power consumption W0 of the temporary target temperature Tt0 obtained in step ST3 is compared with the power consumption W1,... Wn of the candidate temperatures Tt1,. If the power consumption W0 is minimum, the temporary target temperature Tt0 is set as the target temperature and the process proceeds to step ST6. If there is a minimum value in power consumption W1,... Wn of candidate temperatures Tt1,... Ttn, in step ST5, the target temperature is changed from Tt0 to a candidate temperature that gives the minimum value in power consumption W1,. Change (step ST5) and proceed to the next step ST6.

  In step ST6, the thermal storage body temperature control unit 20e acquires the ambient temperature Ta after a predetermined time has elapsed. And the heat storage body temperature control part 20e considers how much ambient temperature Ta has changed from the value at the time of calculating the present target temperature. This is because if the ambient temperature Ta changes greatly, it may be necessary to change the target temperature in order to keep the energy efficiency small. When it is determined in the heat storage body temperature control unit 20e that the change in the ambient temperature Ta has exceeded a predetermined threshold, the process proceeds to step ST8. If the change in the ambient temperature Ta is within the predetermined threshold range in step ST6, the process proceeds to step ST7.

  In step ST7, the heat storage body temperature control part 20e examines the change of heat energy utilization information. For example, the energy demand of the air conditioner 2 may vary greatly depending on the usage conditions, such as during the day in the summer, when the demand for cooling is higher than in the morning, and the target temperature is changed accordingly. This may be necessary to change. In the heat storage body temperature control unit 20e, for example, if it is determined that changes in the heat exchanger input energy (Qvrvc-Qvrvh), the cooling energy Qcd of the air conditioner, or the heating energy Qhd ambient temperature Ta exceed a predetermined threshold, step Proceed to ST8. If the change in the heat energy utilization information is within a predetermined threshold range in step ST7, the process proceeds to step ST9.

  In step ST8, the control unit 20 changes the current target temperature to a temporary target temperature. Then, the control unit 20 repeats the calculation from step ST2 using the changed temporary target temperature.

  In step ST9, it is determined whether or not an operation stop instruction has been issued. If there is no instruction to stop the operation, the process returns to step ST6 to monitor whether there is a change in the ambient temperature Ta or a change in the heat energy utilization information. On the other hand, when an instruction to stop the operation is given, the actual operation such as the current target temperature is recorded and the operation is stopped for the next start-up (step ST10).

  Whether or not the low temperature side 6a of the heat storage tank 6 is at the target temperature is monitored by the temperature sensor 26a based on the target temperature obtained by calculation by the heat storage body temperature control unit 20e of the control unit 20. And the thermal storage body temperature control part 20e controls the heat source 7 and the pump group 38 so that the difference of target temperature and measured temperature may be eliminated.

  In the above description, the case where the cooling load is large has been described. However, when the heating load is larger, since Qvrvc <Qvrvh, the sign is changed and the heat exchanger input energy (Qvrvh−Qvrvc) is calculated. To do. Further, COPchh, which is a coefficient of performance when heating the water heating medium 5, is used for COP of the heat source 7.

[Second Embodiment]
<Configuration of heat storage system>
The heat storage system 1 of 1st Embodiment is divided into the low temperature side 6a with relatively low temperature of the hydrothermal medium 5, and the high temperature side 6b with high temperature in the one heat storage tank 6. FIG. However, the temperature gradually changes between the low temperature side 6a and the high temperature side 6b of the heat storage tank 6, and the heat storage tank 6 is not separated into two different temperatures by partitioning. The heat storage system of the second embodiment is configured so that the heat storage tank 6 can be divided into a plurality of areas and different temperatures can be set for each area.

  Drawing 4 is a figure for explaining the composition of the heat storage tank concerning the 2nd embodiment, and the piping of the circumference. The heat storage system 1A shown in FIG. 4 is different from the heat storage system 1 shown in FIG. 1 in that the heat storage tank 60 is divided into four areas, whereas the heat storage tank 6 is not divided. The heat storage tank 60 includes a first tank 60a, a second tank 60b, a third tank 60c, and a fourth tank 60d, and is divided so that the volumes of the tanks are substantially equal. Pipes 61, 62, and 63 are connected between the first tank 60a and the second tank 60b, between the second tank 60b and the third tank 60c, and between the third tank 60c and the fourth tank 60d, respectively. ing. The pipes 61, 62, and 63 extend from a deep part of the second tank 60b, the third tank 60c, and the fourth tank 60d to a shallow part of the adjacent first tank 60a, the second tank 60b, and the third tank 60c, respectively. ing. Thereby, the relatively low temperature hydrothermal medium 5 located deep in the second tank 60b, the third tank 60c, and the fourth tank 60d moves to the first tank 60a, the second tank 60b, and the third tank 60c. Alternatively, the hydrothermal medium 5 having a relatively high temperature located in a shallow area of the first tank 60a, the second tank 60b, and the third tank 60c moves to the second tank 60b, the third tank 60c, and the fourth tank 60d.

  Branch pipes 10c1, 10c2, 10c3, 10c4, 10d1, 10d2, 10d3, 10d4 are provided in the pipes 10c, 10d, respectively, and the branch pipes 10c1, 10c2, 10c3, 10d1, 10d2, 10d3, 10d4 are opened and closed, respectively. Valves 41, 42, 43, 44 and open / close valves 51, 52, 53, 54 are provided. The hydrothermal medium 5 can be supplied to the first tank 60a from the heat source 7 through the branch pipe 10c1 or the branch pipe 10d4. Similarly, the second tank 60b, the third tank 60c, and the fourth tank 60d are respectively connected to the first tank 60a from the heat source 7. The hydrothermal medium 5 is configured to be supplied by branch pipes 10c2, 10c3, 10c4 or branch pipes 10c2, 10c3, 10c4.

  For example, when the cooling load is larger than the heating load, a relatively low-temperature hydrothermal medium 5 is supplied to the air conditioner 2 by the pipe 10a, but the heat capacity to be supplied is determined by the size of the cooling load. When supplying from the 1st tank 60a and the 2nd tank 60b compared with the case where it supplies only from the 1 tank 60a, the temperature of the hydrothermal medium 5 can be set high. For example, even when only the first tank 60a is set to 20 ° C., both of the first tank 60a and the second tank 60b can be set to 25 ° C.

  The use of the divided areas as described above is shown in FIG. FIG. 5A shows a state in which only the first tank 60a is controlled to 20 ° C. For this purpose, the water heat medium 5 having a temperature lower than 20 ° C. is supplied from the heat source 7 to the first tank 60a through the branch pipe 10c1, and the water heat medium at 20 ° C. is supplied from the first tank 60a to the air conditioner 2 through the pipe 10a. 5 is supplied, and the heated water heating medium 5 is returned from the air conditioner 2 to the fourth tank 60d through the pipe 10b. At this time, in order to supply the hydrothermal medium 5 from the heat source 7 to the first tank 60a, the cooling / heating switching valves 15a, 15d and the opening / closing valves 41, 51 are opened, and the other cooling / heating switching valves 15b, 15c and the opening / closing valves 42, 43. , 44.52.53.54 are closed. Therefore, the 2nd tank 60b, the 3rd tank 60c, and the 4th tank 60d are comparatively high temperature by the hydrothermal medium 5 returned from the air conditioning apparatus 2, and are 30 degreeC in Fig.5 (a). However, since the temperature of 30 ° C. is not the result of temperature control, it varies depending on the ambient temperature and the use state of the air conditioner 2.

  FIG. 5B shows a state in which the first tank 60a and the second tank 60b are controlled at 25 ° C. For this purpose, the water heat medium 5 having a temperature lower than 25 ° C. is supplied from the heat source 7 to the second tank 60b through the branch pipe 10c2, and the water heat medium at 25 ° C. is supplied from the first tank 60a to the air conditioner 2 through the pipe 10a. 5 is supplied, and the heated water heating medium 5 is returned from the air conditioner 2 to the fourth tank 60d through the pipe 10b. At this time, in order to supply the hydrothermal medium 5 from the heat source 7 to the second tank 60b, the cooling / heating switching valves 15a, 15d and the opening / closing valves 42, 51 are opened, and the other cooling / heating switching valves 15b, 15c and opening / closing valves 41, 43 are opened. , 44, 52, 53, 54 are closed. Therefore, the 3rd tank 60c and the 4th tank 60d are comparatively high temperature by the hydrothermal medium 5 returned from the air conditioning apparatus 2, and are 30 degreeC in Fig.5 (a). However, since the temperature of 30 ° C. is not the result of temperature control, it varies depending on the ambient temperature and the use state of the air conditioner 2.

  The heat storage system 1A according to the second embodiment and the heat storage system 1 according to the first embodiment are structurally different between the cooling / heating switching valves 11a, 11b, 11c, 11d and the cooling / heating switching valves 15a, 15b, 15c, 15d. It is a part in. Therefore, the configuration between the cooling / heating switching valves 11a, 11b, 11c, 11d and the air conditioner 2 and the configuration from the cooling / heating switching valves 15a, 15b, 15c, 15d to the heat source 7 are the heat storage system 1A of the second embodiment. However, it is the same as the heat storage system 1 of the first embodiment.

<Effects of heat storage tank division>
While comparing the two states of FIG. 5A and FIG. 5B, what kind of selection is performed in relation to energy efficiency will be described. Comparing FIG. 5 (a) and FIG. 5 (b), in general, FIG. 5 (a) can be expected to have a relatively high energy efficiency in the air conditioner 2, but there is a heat dissipation loss in the heat storage tank 60. There is a tendency to grow. On the other hand, in FIG. 5B, the heat dissipation loss of the heat storage tank 60 can be reduced although the energy efficiency of the air conditioner 2 is inferior. To explain this numerically, the cooling load is 30 [kW], the COP of the air conditioner 2 is 3 at the target temperature 20 ° C. of the hydrothermal medium 5 and 2 at 25 ° C., and the heat dissipation loss is the target temperature. It is assumed that the temperature is 4 [kW] at 20 ° C. and 0 [kW] at 25 ° C., and the COP of the heat source 7 is 2 at a target temperature of 20 ° C. and 3 at 25 ° C. Then, the energy W20 required when the target temperature is 20 ° C. is given by W20 = {4+ (1 + 1 ÷ 3) × 30} ÷ 2 + 30 ÷ 3, and W20 = 32 [kW]. On the other hand, the energy W25 required when the target temperature is 25 ° C. is given by W25 = 0 + (1 + 1 ÷ 2) × 30} ÷ 3 + 30 ÷ 2, and W25 = 30 [kW]. Therefore, under the above assumption, the state shown in FIG. However, when the heat source 7 is not considered under the above assumption, W20 = 14 and W25 = 15, so that W20 <W25, and conversely, FIG. 5A is preferable. . As described above, when the target temperature is determined in consideration of only the heat energy utilization status of the air conditioner 2 and the heat dissipation loss of the heat storage tank 60, the overall energy efficiency may be deteriorated.

  In the above description, two cases of controlling only the first tank 60a to the target temperature and controlling the first tank 60a and the second tank 60b to the target temperature have been compared. However, since the heat storage tank 60 consists of four areas of the first tank 60a, the second tank 60b, the third tank 60c, and the fourth tank 60d, four combinations are possible, and four combinations are considered. You may be able to. For example, in addition to the cases shown in FIGS. 5 (a) and 5 (b), when three tanks are controlled at 27 ° C. as shown in FIG. 5 (c), and as shown in FIG. For example, when two tanks are controlled at 28 ° C.

<Target temperature control>
In determining the target temperature, the heat storage system 1A of the second embodiment differs from the heat storage system 1 of the first embodiment in that the area of the heat storage tank 60 must be taken into consideration. This point will be described with reference to the flowchart of FIG.

  When candidate temperatures Tt1,... Ttn are determined in step ST2, it is necessary to determine how many areas of the heat storage tank 60 are used for the candidate temperatures Tt1,. This is determined from the heat capacity required by the air conditioner 2. Therefore, the control part 20 acquires the data regarding the heat capacity required from the air conditioning apparatus 2. FIG. The heat capacity stored in the heat storage tank 60 must be larger than the heat capacity required by the air conditioner 2, but if the excess water heat medium 5 is kept at the target temperature, the heat dissipation loss increases. Therefore, the number of areas to be used is the smallest as long as the necessary heat capacity can be secured.

  Moreover, in step ST2, when acquiring a heat dissipation loss, it is necessary to supplement the point that heat insulation changes with the number of areas to be used. Even if the target temperature of the hydrothermal medium 5 stored in the heat storage tank 60 is the same, for example, when only the first tank 60a is used and when the first tank 60a and the second tank 60b are used, the surface area is different. The latter is less heat insulating. For this purpose, the heat storage tank heat radiation characteristic storage unit 20h describes data that takes into consideration the heat insulation that varies depending on the number of areas, and the heat radiation loss acquisition unit 20c acquires the heat radiation loss data using the number of areas as a parameter. Similar to the heat storage system 1 of the first embodiment, the target temperature can be obtained according to the flowchart of FIG. 3 except that the heat dissipation loss of the heat storage tank 60 is different because the heat insulation property changes.

[Third Embodiment]
Next, the heat storage system by 3rd Embodiment is demonstrated using FIG. The heat storage system 1B of the third embodiment shown in FIG. 6 is configured so that natural energy such as a hot spring, a river, and well water can be used as a heat source. In the heat storage system 1B, the configuration other than the heat source is the same as that of the heat storage system 1 of the first embodiment, and the parts denoted by the same reference numerals have already been described in the description of the first embodiment, so the description of these parts is omitted. To do. Also in the heat source, the first heat source 7 is a plurality of chillers 7a,... 7b as in the heat storage system 1 of the first embodiment. Since the configuration of the heat source 7 is the same as that of the first embodiment, the description thereof is omitted.

  What is newly added in the heat storage system 1B of the third embodiment is the configuration of the second heat source 71, the third heat source 72, and their surroundings. The heat source 71 can supply the hydrothermal medium 5 that can be used for heating because the temperature is relatively high, such as hot springs and hot water in a bath. The heat source 71 is configured, for example, by storing hot springs of 40 ° C. in the storage tank 71a, and therefore does not require energy for increasing the temperature of the hydrothermal medium 5. The water heating medium 5 stored in the storage layer 71a is supplied to the high temperature side 6b of the heat storage tank 6 through the pipe 10e. For this purpose, a pump 80 is provided in the pipe 10e. Further, a temperature sensor 84 and a flow meter 88 are attached to the pipe 10e in order to measure the temperature and flow rate of the hydrothermal medium 5 supplied through the pipe 10e. If the water heating medium 5 is simply sent from the storage layer 71a to the heat storage tank 6, the water heating medium 5 is overflowed. Therefore, the water heat medium 5 is returned from the low temperature side 6a of the heat storage tank 6 through the pipe 10f by the same amount as that sent from the storage tank 71a. Yes. Further, a temperature sensor 85 is attached to the pipe 10f in order to measure the temperature of the hydrothermal medium 5 returned by the pipe 10f. The COP of the second heat source 71 is determined by the power consumption of the pump 80.

  Generally, when natural energy such as hot springs is used, the energy efficiency is increased. Therefore, the first heat source is mainly used when heat energy is supplied mainly by the second heat source 71 and the amount of hot springs is small and cannot be fully covered. 7 may be combined. Thus, when supplying heat energy by the combination of two or more types of heat sources, the target temperature is calculated using the COP as a whole when combined. For this purpose, the COP when the first heat source 7 and the second heat source 71 are used in combination with the target temperature is described in advance in the heat source COP storage unit 20i of FIG. How to combine the first heat source 7 and the second heat source 71 with respect to the target temperature is determined in advance by, for example, experiments or simulations.

  The third heat source 72 is capable of supplying the water heat medium 5 that can be used for cooling because the temperature is relatively low, such as in rivers and well water. Since the heat source 72 is configured by, for example, storing 15 ° C. well water in the storage tank 72a, energy for lowering the temperature of the hydrothermal medium 5 is not required. The water heating medium 5 stored in the storage layer 72a is supplied to the low temperature side 6a of the heat storage tank 6 through the pipe 10g. Therefore, a pump 82 is provided in the pipe 10g. Further, a temperature sensor 86 and a flow meter 90 are attached to the pipe 10g in order to measure the temperature and flow rate of the hydrothermal medium 5 supplied through the pipe 10g. Since only the amount of water heating medium 5 sent from the reservoir 72a to the heat storage tank 6 overflows, the amount of water heating medium 5 is returned from the high temperature side 6b of the heat storage tank 6 through the pipe 10h by the same amount as that sent from the storage tank 72a. Yes. Further, a temperature sensor 87 is attached to the pipe 10h in order to measure the temperature of the hydrothermal medium 5 returned by the pipe 10h. Therefore, the COP of the third heat source 72 is determined by the power consumption of the pump 82.

  Generally, when natural energy such as well water is used, the energy efficiency is increased. Therefore, the first heat source is mainly used when the thermal energy is supplied mainly by the third heat source 72 and the amount of hot springs is small and cannot be covered. 7 may be combined. Thus, when supplying heat energy by the combination of two or more types of heat sources, the target temperature is calculated using the COP as a whole when combined. Therefore, the COP when the first heat source 7 and the third heat source 72 are used in combination with the target temperature is described in advance in the heat source COP storage unit 20i of FIG.

  The pumps 80 and 82 belong to the pump group 38 in FIG. 2 and are controlled by the control unit 20. Further, since the temperature sensors 85 and 87 measure the corresponding temperature before applying the heat energy, they belong to the heat source heat medium inlet temperature sensor 28 of FIG. 2, and the temperature sensors 84 and 86 set the corresponding temperature after applying the heat energy. 2 belongs to the heat source heat medium outlet temperature sensor 29 in FIG. 2, the flow meters 88 and 90 belong to the heat source heat medium flow meter 34, and are necessary for acquiring the COP of the heat source in the heat source COP acquisition unit 20 d of the control unit 20. Give a good measurement. How to combine the first heat source 7 and the third heat source 72 with respect to the target temperature is determined in advance by, for example, experiments or simulations.

  As described above, the heat storage system 1 of the first embodiment and the heat storage system 1B of the third embodiment differ only in the acquisition of the COP of the heat source. Therefore, also in the heat storage system 1B, the target temperature is determined through a process similar to the process of determining the target temperature of the heat storage system 1 described with reference to FIG.

<Modification>
(A) In the above-described embodiment, the air conditioner 2 that performs cooling and heating is described as an example of the heat utilization device that uses the thermal energy of the heat storage systems 1, 1 </ b> A, 1 </ b> B. It may be another cooling or heating system such as an air conditioner or a floor heating system to be performed, or may include another heat energy utilization part such as a hot water supply system. The type of the air conditioner may be other than the building multi-type air conditioner including the variable refrigerant flow rate control system that can change the flow rate of the heat medium by a pump or the like, like the air conditioner 2. In addition, there is a so-called cooling / heating-free air conditioning in which both cooling and heating can be performed in one system, but from the viewpoint of the storage systems 2, 2A, 2B, the amount of energy supplied to one system and the system The variation of the correspondence of the coefficient of performance only increases. Therefore, if the correspondence between the operating condition of the cooling / heating-free air conditioner and the coefficient of performance is grasped beforehand by actual measurement or simulation, the cooling / heating-free air conditioner can be However, it is possible to apply the heat storage systems 1, 1A, 1B.

  (B) In the above embodiment, the outdoor units 3a,... 3b, the heat storage tanks 6, 60, and the heat source 7 of the air conditioner 2 have been described on the assumption of the dry bulb temperature. When doing so, the wet bulb temperature may be taken into account. For example, if the heat storage tanks 6 and 60 are open types, heat loss due to evaporation of water is added, so that the surrounding humidity can be considered.

  (C) Although the case where the heat storage tank 60 is divided into four has been described in the second embodiment, the number of areas to be divided is not limited to four. However, in order to change the number of areas, it is preferable to divide into three or more. Further, the volume ratio and shape of each area when dividing are not necessarily the same, and can be appropriately changed according to the method of use.

  (D) In the above-described embodiment, the case where information such as heat energy utilization information is acquired using a sensor or measuring instrument has been described. However, such information is information obtained based on actual measurement using a sensor or measuring instrument. Not limited to. For example, the thermal energy usage information can be estimated from building usage information (such as accommodation reservation information in the case of a hotel) and the season. It can also be estimated from the internal information of the air conditioner 2. As described above, information and coefficients obtained based on the estimated value may be used as information and coefficients necessary for calculating the target temperature of the heat storage body such as heat energy utilization information.

<Features>
(1)
The heat storage systems 1, 1 </ b> A, 1 </ b> B supply heat energy to the air conditioner 2, which is a heat utilization device, using a water heat medium 5. The water heat medium 5 is housed in the heat storage tanks 6 and 60 and also functions as a heat storage body that stores thermal energy by sensible heat called a temperature difference of the water heat medium 5. The heat sources 7, 71, 72 include not only those that use other energy sources such as chillers 7a,... 7b, but also those that use heat energy that is stored naturally, such as hot springs and well water. It is.

  In order to calculate the target temperature, the heat storage systems 1, 1 </ b> A, 1 </ b> B acquire the thermal energy usage information by the thermal energy usage information acquisition unit 20 a (thermal energy usage information acquisition unit), and the air conditioner COP acquisition unit 20 b (the usage side) The COP related to the air conditioner 2 is acquired by the coefficient of performance acquisition means), the heat dissipation loss of the heat storage tanks 6, 60 is acquired by the heat dissipation loss acquisition unit 20c (heat dissipation loss acquisition means), and the heat source COP acquisition unit 20d (heat source side coefficient of performance) The COP of the heat sources 7, 71, 72 is acquired by the acquisition means).

  The heat storage body temperature controller 20e of the heat storage system 1, 1A, 1B is W (Tt) = (Qloss (Tt) + (1 + 1 / COPvrvc (Tt)) × Qcd− (1-1 / COPvrvh (Tt)) × Qhd) / COPch (Tt) + Qcd / COPvrvc (Tt) + Qhd / COPvrvh (Tt) or W (Tt) = (Qloss (Tt) + Qvrvc−Qvrvh) / COPch (Tt) + Qcd / COPvrvc (Tt) + Qhd / COPvrvh The power consumption W is calculated by the equation (Tt). Since the calculated power consumption W (Tt) is a function of the target temperature Tt, the power consumption W can be kept low by selecting the target temperature Tt that gives the minimum value of this function.

  That is, in this equation, the energy use efficiency of the air conditioner 2 (heat utilization device) is affected by the target temperature Tt, the energy loss in the heat storage tanks 6 and 60 is also affected by the target temperature Tt, and the heat sources 7, 71, It shows that the energy efficiency when storing heat from 72 is also affected by the target temperature Tt. By taking these effects into consideration, the overall energy use efficiency can be improved. In this way, if the target temperature is calculated in consideration of the overall energy efficiency including the air conditioner 2 (heat utilization device) and the heat storage system 1, 1A, 1B, the target of the heat storage body is improved so that the overall energy efficiency is improved. Temperature can be set. And if the above formula is used, the target temperature can be set so as to keep the power consumption low.

  Moreover, the heat storage system 1, 1A, 1B uses the water heat medium 5 as a heat storage body and a heat medium. Since water has a large specific heat, water is excellent as a heat storage body that stores thermal energy by sensible heat in that the volume can be reduced and heat dissipation loss can be suppressed. In addition, since the hydrothermal medium 5 is stable and easy to handle, the target temperature can be easily calculated and controlled such that there is no temperature range in which the use is restricted from the viewpoint of safety in the operating temperature range. It is also advantageous when using naturally stored energy such as rivers and well water.

(2)
The heat storage system 1A includes a heat storage tank 60 including a plurality of areas of a first tank 60a, a second tank 60b, a third tank 60c, and a fourth tank 60d. These four areas (first tank 60a, second tank 60b, third tank 60c, and fourth tank 60d) have temperature sensors 26a0, 26a1, 26a2, 26a3, 26b0, 26b1, 26b2, and 26b3, and heat sources, respectively. 7 are provided with branch pipes 10c1, 10c2, 10c3, 10c4 and branch pipes 10d1, 10d2, 10d3, 10d4 that receive the supply of the hydrothermal medium 5 from the heater 7, so that the target temperature can be controlled for each tank by the heat storage body temperature controller 20e. It is configured. For example, when only the first tank 60a can cover the heat capacity, the volume of the control object is limited to the volume of the first tank 60a by making only the first tank 60a a control target of the target temperature Tt, so that the energy loss can be reduced. There is. On the other hand, if the first tank 60a and the second tank 60b are used to cover the above-described heat capacity, the target temperature Tt may be set in the vicinity of the ambient temperature Ta, and the energy loss may be reduced. By enabling such a plurality of selections, it is possible to provide an aspect in which both improvement of heat dissipation loss of the heat storage tank and improvement of overall energy loss can be achieved.

1, 1A, 1B Heat storage system 2 Air conditioner 3a, ... 3b Outdoor unit 5 Water heat medium 6, 60 Heat storage tank 7, 71, 72 Heat source

JP-A-8-75220

Claims (5)

A heat storage system (1, 1A, 1B) for supplying heat energy used in the heat utilization device (2),
A heat storage body (5) for supplying heat energy to the heat utilization device and storing the heat energy by sensible heat;
A heat storage tank (6, 60) for housing the heat storage body;
A heat source (7, 71, 72) for supplying thermal energy to the heat storage body;
Thermal energy usage information acquisition means (20a) for acquiring thermal energy usage information relating to thermal energy usage status in the heat usage device;
A utilization side coefficient of performance acquisition means (20b) for acquiring a utilization side coefficient of performance of the heat utilization device corresponding to the heat energy utilization information;
A heat dissipation loss acquisition means (20c) for acquiring a heat dissipation loss of the heat storage tank;
Heat source side coefficient of performance acquisition means (20d) for acquiring the heat source side coefficient of performance of the heat source;
The thermal energy usage information acquired by the thermal energy usage information acquisition means, the usage-side performance coefficient acquired by the performance coefficient acquisition means, the heat dissipation loss acquired by the heat dissipation loss acquisition means, and the heat source side acquisition means acquired A heat storage system comprising: a heat storage body temperature control means (20e) that calculates a target temperature of the heat storage body based on the heat source side coefficient of performance and controls the temperature of the heat storage body. The heat utilization device is an air conditioner (2),
The thermal energy usage information acquisition means acquires the thermal energy usage information of cooling energy Qcd of the air conditioner and heating energy Qhd of the air conditioner,
The usage-side coefficient of performance acquisition means acquires the usage-side coefficient of performance COPvrvc of cooling of the air conditioner and the coefficient of performance COPvrvh of heating of the air conditioner,
The heat dissipation loss acquisition means acquires the heat dissipation loss Qloss of the heat storage tank,
The heat source side coefficient of performance acquisition means acquires the coefficient of performance COPch of the heat source,
The heat storage body temperature control means reduces the power consumption W given by the equation W = (Qloss + | (1 + 1 / COPvrvc) × Qcd− (1-1 / COPvrvh) × Qhd |) / COPch + Qcd / COPvrvc + Qhd / COPvrvh The heat storage system according to claim 1, wherein the target temperature is changed to control the temperature of the heat storage body. The heat utilization device is an air conditioner (2),
The heat energy utilization information acquisition means uses the heat energy utilization information as heat exchanger input energy (Qvrvc-Qvrvh) of the air conditioner, cooling energy Qcd of the air conditioner, and heating energy Qhd of the air conditioner. Acquired,
The usage-side coefficient of performance acquisition means acquires the usage-side coefficient of performance COPvrvc of cooling of the air conditioner and the coefficient of performance COPvrvh of heating of the air conditioner,
The heat dissipation loss acquisition means acquires the heat dissipation loss Qloss of the heat storage tank,
The heat source side coefficient of performance acquisition means acquires the coefficient of performance COPch of the heat source,
The heat storage body temperature control means changes the target temperature in a direction to reduce the power consumption W given by the equation W = (Qloss + | Qvrvc−Qvrvh |) / COPch + Qcd / COPvrvc + Qhd / COPvrvh. The heat storage system according to claim 1 to be controlled. The heat storage tank is composed of three or more areas (60a, 60b, 60c, 60d),
The heat storage body is divided and accommodated in the plurality of areas,
The heat storage system according to any one of claims 1 to 3, wherein the heat storage body temperature control means controls the temperature of the plurality of areas for each area.   The heat storage system according to any one of claims 1 to 4, wherein the heat storage body is water (5).

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