JP2005077038A - Ice heat storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent excessive cooling in generation of supercooled water or ensure the heat quantity of a refrigerant used for preheating of water before supercooling even when the outside air temperature is low in a supercooled water type ice heat storage device. <P>SOLUTION: This ice heat storage device comprises a refrigeration cycle, a plurality of heat storage cycles, a cooling water cycle, flowmeters 24 and 26 for detecting freezing of water in the heat storage cycles, a preheater 7 for performing heat exchange between the refrigerant after concentration and the water before supercooling, a temperature sensor for detecting the temperature of the cooling water for cooling the refrigerant, and an operation control part 50. The operation control part 50 controls, at the time of freezing of water, the output of a compressor 1 to a value obtained by deducing the output of the compressor 1 to the heat storage cycle where freezing of water is caused, and controls the output of a cooling water pump 33 and the compressor 1 according to the temperature of the cooling water detected by the temperature sensor so that the temperature of the refrigerant in a condenser 2 is not lower than the cooling water temperature in rated operation of the cooling pump 33 and not higher than a set value of temperature of the refrigerant in the condenser 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ice heat storage device having a refrigeration cycle and a heat storage cycle, and more particularly to an ice heat storage device that preheats water circulating in the heat storage cycle before supercooling by heat generated in the refrigeration cycle.

  As an ice heat storage device, water is supercooled by the cold heat generated in the refrigeration cycle, the supercooled water obtained is released to generate ice water, and this is stored in an ice heat storage tank to store the refrigeration cycle. 2. Description of the Related Art A supercooled water type ice heat storage device that stores cold heat generated in the above is known. In such a supercooled water type ice heat storage device, preheating water before supercooling so that fine ice particles do not flow into the supercooler (heat exchanger that produces supercooled water) This is an important operation for normal and smooth operation of the device.

  As an ice heat storage device that preheats water before supercooling, a device that uses a high-temperature and high-pressure refrigerant liquid that circulates in the refrigeration cycle as a preheat source of water before supercooling is known (for example, Patent Documents). 1 and 2). These ice heat storage devices are excellent in that a highly efficient refrigerant subcooling cycle can be realized in the refrigeration cycle. In addition, these ice heat storage devices are excellent in preventing the amount of preheating from becoming excessive because the heat exchanger for preheating can be bypass-controlled.

  However, in order to produce supercooled water efficiently and stably in a supercooled water type ice heat storage device, not only is it possible to prevent an excessive amount of preheat, but also to prevent excessive cooling of the supercooled water, It is important to ensure a stable amount of heat.

  For example, in an ice heat storage device in which a plurality of supercoolers are installed for the refrigeration cycle, if the supercooler freezes, the freeze release operation is performed quickly. Since it is not used for ice making, excessive heat is generated in the refrigeration cycle. In the conventional supercooled water type ice heat storage device, there remains room for studying the point of preventing such excessive cooling in the generation of supercooled water.

In the refrigeration cycle, air-cooled cooling water is usually used for refrigerant condensation, but when the outside air temperature is low, the cooling water temperature is lowered, thereby increasing the cooling capacity of the condenser with respect to the refrigerant, A lot of heat is taken from the refrigerant, and the amount of heat of the refrigerant used for preheating may be insufficient. Thus, in the conventional supercooled water type ice heat storage device, there remains room for studying the point of securing the amount of heat of the refrigerant used for preheating water before supercooling.
Japanese Patent No. 3097161 JP-A-10-288361

  This invention makes it the 1st subject to prevent the excessive cooling in the production | generation of supercooling water in the superheated water type ice heat storage apparatus.

  Moreover, this invention makes it the 2nd subject to ensure the calorie | heat amount of the said refrigerant | coolant used for the preheating of the water before supercooling, even when outside air temperature is low in the ice heat storage apparatus of a supercooled water system.

  The present invention relates to a supercooled water type ice heat storage device, in the case where freezing of water occurs in some of the heat storage cycles of the plurality of heat storage cycles, the compressor operated for the plurality of heat storage cycles. At least the first problem is to be solved by subtracting the output for the heat storage cycle in which water has been frozen from the output.

  That is, the ice heat storage device of the present invention has a refrigeration cycle that generates cold by compression, condensation, expansion, and evaporation of the refrigerant, and a heat storage cycle that stores the cold generated by the refrigeration cycle. A compressor that compresses the vapor, a condenser that cools and condenses the refrigerant compressed by the compressor with cooling water, a decompression unit that adiabatically expands the refrigerant condensed by the condenser, and a refrigerant that is adiabatically expanded by the decompression unit. The heat storage cycle is generated by a supercooler that generates supercooled water by subcooling water to 0 ° C. or lower by cold heat generated by the evaporator of the refrigeration cycle. An ice heat storage device having a supercooling release unit that releases supercooled water from the supercooling state to form ice water, and an ice heat storage tank that stores ice water generated by the supercooling release unit, has a plurality of heat storage cycles, and a heat storage cycle. And detecting means for detecting that the water is frozen in the boiler, and compressor control means for controlling the output of the compressor in accordance with a detection signal from the detection means. When water freezes in the compressor, the compressor output is controlled so that the compressor output for the heat storage cycle in which water freezes is subtracted from the compressor output for all heat storage cycles. An ice heat storage device (hereinafter, this ice heat storage device is also referred to as “first ice heat storage device”).

  According to the above configuration, when water freezes in some heat storage cycles, supply of excessive cold heat to the remaining heat storage cycles is suppressed, and supercooled water is stably generated in the remaining heat storage cycles. And it becomes possible to implement | achieve the energy saving operation in the whole apparatus.

  Further, according to the present invention, in the supercooled water type ice heat storage device, the output of the power source for cooling the coolant is set so that the temperature of the refrigerant in the refrigeration cycle approaches the set value that is the upper limit value thereof. By controlling according to temperature, it intends to solve at least the second problem.

  That is, the ice heat storage device of the present invention has a refrigeration cycle that generates cold by compression, condensation, expansion, and evaporation of the refrigerant, and a heat storage cycle that stores the cold generated by the refrigeration cycle. A compressor that compresses the vapor, a condenser that cools and condenses the refrigerant compressed by the compressor with cooling water, a decompression unit that adiabatically expands the refrigerant condensed by the condenser, and a refrigerant that is adiabatically expanded by the decompression unit. The heat storage cycle is generated by a supercooler that generates supercooled water by subcooling water to 0 ° C. or lower by cold heat generated by the evaporator of the refrigeration cycle. In an ice heat storage device having a supercooling release unit that releases supercooled water from the supercooling state to form ice water, and an ice heat storage tank that stores ice water generated by the supercooling release unit, between the condenser and the pressure reducing means In the condenser Preheater that exchanges heat between the compressed refrigerant and water sent from the ice storage tank of the heat storage cycle to the supercooler, a cooling tower that cools the cooling water, and cooling water between the condenser and the cooling tower Controls the output of at least one of a cooling water cycle having a cooling water pump for circulating the refrigerant, temperature detection means for detecting the temperature of cooling water for cooling the refrigerant, a cooling power source and a compressor in the cooling water cycle An output control means for performing cooling so that the temperature of the refrigerant in the condenser becomes a temperature within a predetermined range in accordance with the temperature of the cooling water detected by the temperature detection means. Means for controlling the output of at least one of the power source for compressor and the compressor, and the predetermined range is when the cooling water obtained during rated operation of the power source for cooling flows during the cooling water cycle. Clump The temperature of the refrigerant more than in the vessel, the ice heat storage device, characterized in that is less than the temperature set value of the refrigerant in the condenser (hereinafter, this ice thermal storage apparatus referred to as a "second ice storage apparatus") is.

According to the above configuration, when the outside air temperature is low, the temperature of the cooling water generated in the cooling tower can be increased or sent to the condenser by operating the cooling power source under conditions that are looser than the rated conditions. The cooling water flow rate can be reduced, and the temperature of the refrigerant in the condenser can be increased compared to when the cooling power source is operated under rated conditions. Therefore, since the condensed refrigerant has more heat than when the cooling power source is operated under rated conditions, it is possible to secure a preheating amount of the supercooling water even when the temperature of the cooling water is low. It becomes possible.

  Further, according to the above configuration, even if the cooling power source is operated under a condition looser than the rated condition, the heat is deprived from the refrigerant in the preheater. Therefore, the cooling power source is rated from this refrigerant. Cold energy equivalent to or higher than the cold energy obtained when operating under conditions can be obtained in the refrigeration cycle. Therefore, according to the above configuration, in the refrigeration cycle, even if the output of the cooling power source is small, it is possible to generate a lot of cold heat, so that at least further energy saving is realized in the operation of the cooling power source. It becomes possible.

  Hereinafter, the ice heat storage device of the present invention will be described in more detail. First, the main structure in the ice thermal storage apparatus of this invention is demonstrated.

  The ice heat storage device of the present invention has a refrigeration cycle and a heat storage cycle. The refrigeration cycle is a cycle that generates cold heat by compressing, condensing, expanding, and evaporating refrigerant, and compresses the refrigerant vapor and condenses the refrigerant compressed by the compressor with cooling water. A condenser for adiabatic expansion of the refrigerant condensed in the condenser, and an evaporator for evaporating the refrigerant adiabatically expanded by the pressure reduction means. The refrigeration cycle can be configured using a known instrument or device.

  The refrigeration cycle may have other components in addition to the components described above. Such other components include, for example, a flow rate adjusting means for adjusting the flow rate of the refrigerant, such as a refrigerant bypass flow path, a distributor, a valve, and a pump provided between the condenser and the pressure reducing means. And refrigerant detection means for detecting the temperature, pressure, and other conditions of the refrigerant in the refrigeration cycle. A known refrigerant can be used as the refrigerant.

  The heat storage cycle is a cycle for storing cold heat generated in the refrigeration cycle, and a supercooler that generates supercooled water by supercooling water to 0 ° C. or less by the cold heat generated in the refrigeration cycle, and this supercooling A supercooling release unit that releases the supercooling state of the supercooling water generated by the cooler to make ice water, and an ice heat storage tank that stores the ice water generated by the supercooling release unit. The said heat storage cycle can be comprised using a well-known instrument, an apparatus, etc.

  The heat storage cycle may have other components in addition to the components described above. Such other components include, for example, flow rate adjusting means for adjusting the flow rate of water or supercooling water during the heat storage cycle, such as a bypass flow path of circulating water, a distributor, a valve, and a pump, and the heat storage cycle. Examples thereof include cold water detection means for detecting a state such as temperature and pressure of water or supercooled water in the inside.

  The supercooler includes a shell-and-tube heat exchanger having a plurality of heat conductive tubes and a shell that wraps the outer peripheral surface of the tube, and a plate having a structure in which a plurality of heat conductive plates are laminated. A known heat exchanger such as a heat exchanger of the type can be used. The subcooler is a plate-type heat exchanger that facilitates the identification of the freezing point when water freezes in the heat storage cycle and the release of this freezing, and the pressure in heat exchange. It is preferable for suppressing the loss.

Note that the transmission of cold heat from the refrigeration cycle to the heat storage cycle may be performed directly in the supercooler, for example, a heat transfer cycle in which brine is circulated between the evaporator and the supercooler, etc. May be performed indirectly using.

  A known supercooler can be used as the supercooler. As such a supercooling release device, for example, an open type container to which supercooling water is supplied, and an open type to which supercooling water is supplied so as to collide with the inner wall of the container or a collision plate in the container, etc. And, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-241705, a closed supercooling release container to which supercooling water is supplied, and the supercooling water in the supercooling release container A hermetic supercooling release device having a release inducing device for inducing the release of the supercooling state can be used. In order to reduce the space required for installation, the subcool release unit is preferably a hermetic supercool release unit.

  The release inducing device in the hermetic supercooling releaser is not particularly limited as long as it can induce the release of the supercooling state of the supercooling water supplied to the supercooling releaser. As such a release inducing device, for example, an ultrasonic vibrator or the like that gives the supercooled water an impact that induces the release of the supercooled state.

  In the case of using the hermetic supercooler, a propagation preventer for preventing the propagation of ice from the subcooler to the supercooler is further provided between the supercooler and the supercooler. It is preferable in order to prevent freezing of water during the heat storage cycle. A known propagation preventer can be used as the propagation preventer.

  As such a propagation preventer, for example, as disclosed in Japanese Patent Application Laid-Open No. 2003-106716, an outer peripheral surface of the tube is formed so as to form a sealed space on the outer peripheral surface side of the tube. The pipe has a gap that communicates the inside of the pipe and the space covered by the outer shell part over the entire circumference on the peripheral wall of the pipe covered with the outer shell part. The outer shell portion is connected to a circulating water bypass passage connecting the circulating water passage upstream of the subcooler and the outer shell portion in the direction of water flow in the heat storage cycle. And a propagation preventer that forms a layer of water having a temperature higher than 0 ° C. on the inner wall surface of the pipe connecting the supercooler and the supercooler.

  Next, the first ice heat storage device in the present invention will be described.

  The first ice heat storage device has a plurality of the heat storage cycles in addition to the main components described above. The plurality of heat storage cycles may be any cycle in which at least supercooled water is generated at a plurality of locations. As such a plurality of heat storage cycles, for example, a plurality of heat storage cycles in which the respective cycles are completely independent, or a heat storage cycle in which a plurality of subcoolers are connected in parallel and other components are shared. In addition, a heat storage cycle having a plurality of supercoolers and a plurality of supercooling release devices corresponding to these, and other components are supplied. The plurality of subcoolers may be the same type of subcoolers or different types of subcoolers.

  The first ice heat storage device further includes detection means for detecting that water has frozen in the heat storage cycle, and compressor control means for controlling the output of the compressor in accordance with a detection signal from the detection means. Have.

  The detection means is not particularly limited as long as it can detect that water has frozen during the heat storage cycle. Examples of such detection means include a flow meter that detects the flow rate of water flowing through the heat storage cycle, and a pressure gauge that detects the pressure of the water. One type of these may be used for the detection means, or a plurality of types may be used in combination. Moreover, the detection means is not particularly limited in terms of the number of installations and installation locations as long as it can detect that water has frozen during the heat storage cycle. The detection means is preferably a flow meter from the viewpoint of detection accuracy when detecting freezing of water.

  The compressor control means has a value obtained by subtracting the output of the compressor for the heat storage cycle in which water freezes from the output of the compressor for all the heat storage cycles when water freeze occurs during the heat storage cycle. It is means for controlling the output of the compressor.

  The value obtained by subtracting the compressor output for the heat storage cycle in which water has been frozen is the value obtained by subtracting the compressor output for the heat storage cycle in which water has been frozen from the compressor output for all heat storage cycles. If it is a method by which is calculated | required, it will not specifically limit. As a method of obtaining such a value, for example, a method of subtracting the output of the heat storage cycle in which water has been frozen from the output of the compressor for all the heat storage cycles, or the number of heat storage cycles in which water is not frozen For example, a method of multiplying the ratio by the total number of heat storage cycles can be used. Further, the output of the compressor that is involved in the heat storage cycle in which the water has been frozen may be an actual value measured in advance under a predetermined condition, or may be a theoretical value obtained by simulation or the like.

  The compressor has an inverter, and the compressor control means preferably transmits a control signal to the inverter in order to realize the energy saving operation of the first ice heat storage device.

  Next, the second ice heat storage device in the present invention will be described.

  In addition to the main components described above, the second ice heat storage device is provided between the condenser and the pressure reducing means, and the refrigerant condensed in the condenser and the ice heat storage tank are transferred to the supercooler. It further has a preheater for exchanging heat with water to be sent. As the preheater, the above-mentioned known heat exchanger can be used. The refrigerant used for heat exchange in the preheater may be the total amount or a part of the refrigerant sent from the condenser to the decompression means. Further, the water used for heat exchange in the preheater may be the total amount or a part of the water sent from the ice heat storage tank to the supercooler. The supply amount of the refrigerant and water to the preheater can be adjusted by the flow rate adjusting means such as the bypass flow path described above.

  The second ice heat storage device further includes a cooling water cycle that generates cold heat of cooling water for condensing the refrigerant in the refrigeration cycle. The cooling water cycle includes a cooling tower that cools the cooling water, and a cooling water pump that circulates the cooling water between the condenser and the cooling tower. The cooling water cycle can be configured using a known instrument or device.

  The second ice heat storage device further includes temperature detecting means for detecting a temperature of cooling water for cooling the refrigerant. The temperature detection means is not particularly limited as long as it is a thermometer capable of transmitting a detection result as an electric signal. A known temperature sensor can be used as such temperature detection means. The temperature of the cooling water for cooling the refrigerant is not particularly limited as long as it is the temperature of the cooling water after cooling in the cooling tower and before being used for cooling the refrigerant in the condenser, but the cooling water at the condenser inlet It is preferable to reduce the difference between the set value and the actual value in the control.

  The second ice heat storage device further includes output control means for controlling the output of at least one of the power source for cooling and the compressor in the cooling water cycle. The output control means may control only the output of the cooling power source, may control only the output of the compressor, or may control both of these outputs. The cooling power source means one or more devices used for cooling the cooling water in the cooling water cycle. Examples of such a cooling power source include a cooling tower fan that blows outside air in contact with cooling water in the cooling tower, the cooling water pump, and the like. The cooling power source is preferably a cooling water pump that greatly contributes to the cooling effect of the refrigerant in order to easily perform the output control.

  The output control unit includes the cooling power source and the cooling unit such that the temperature of the refrigerant in the condenser becomes a temperature within a predetermined range according to the temperature of the cooling water detected by the temperature detection unit. The output of at least one of the compressors is controlled. The predetermined range is a range that is equal to or higher than the temperature of the refrigerant in the condenser when cooling water obtained during rated operation of the cooling power source is flowing, and is equal to or lower than the set value of the temperature of the refrigerant in the condenser. It is.

  The temperature of the refrigerant in the condenser when the cooling water obtained at the rated operation of the cooling power source is flowing is a condenser with respect to the temperature of the cooling water when the cooling power source is operated at the rated operation. It is possible to obtain it by simulation of a refrigeration cycle when the measured value of the refrigerant temperature or the operating condition of the power source for cooling is rated operation and the temperature of the cooling water is changed. The rated operation means operation at a specified use limit. Specifically, the operation at the maximum flow rate of the cooling water pump and the operation at the maximum wind speed of the cooling tower fan can be mentioned.

  The set value of the temperature of the refrigerant in the condenser is a value for stably realizing the generation of the cold energy required for the refrigeration cycle while including the amount of preheating to be secured. It is arbitrarily determined according to the required amount of cold generation, design conditions such as the heat transfer area and K value of the preheater, the flow rate of water flowing through the preheater in the heat storage cycle, and the like. As such a set value, for example, an upper limit value of the temperature of the condensed refrigerant at which the compressor can operate normally, or an upper limit value of the refrigerant temperature in the condenser capable of generating cold heat that satisfies the cold load in the heat storage cycle. A value obtained by further adding a value or a value obtained by converting the amount of preheating to water in the preheater into a temperature to the upper limit value, or the like can be given.

  In the present invention, as long as the value is within the predetermined range, an arbitrary range having an appropriate set value as a lower limit value and an upper limit value can be set according to various conditions such as the purpose of control. Examples of such an arbitrary range include a range in which the temperature of the refrigerant in the condenser for securing the preheating amount is set as a lower limit and the compressor can be normally operated, and the temperature of the refrigerant in the condenser is set as an upper limit. It is done.

  The output control means controls the output of at least one of the cooling power source and the compressor so that the sum of the power consumption of the cooling power source and the power consumption of the compressor is minimized. This is preferable for realizing energy saving operation and securing the amount of water preheated in the preheater. The minimum value of the sum of the power consumption of the cooling power source and the power consumption of the compressor is the relationship between the amount of cooling water and the output of the cooling water pump, the temperature of the refrigerant in the condenser, and the output of the compressor. And various conditions such as heat transfer characteristics in the condenser of cooling water and refrigerant. The above-mentioned various conditions can be obtained by actual measurement values when the refrigeration cycle is actually operated by changing the output of the cooling power source, or by simulation of the refrigeration cycle when the output of the cooling power source is changed. Is possible.

  In order to realize the energy saving operation of the second ice heat storage device, it is preferable that the cooling power source and the compressor have an inverter, and the output control means transmits a control signal to the inverter.

  The first ice heat storage device and the second ice heat storage device in the present invention have been described above, but the present invention includes an ice heat storage device in which these ice heat storage devices are combined.

The ice heat storage device according to the present invention includes a plurality of heat storage cycles in the ice heat storage device having the refrigeration cycle and the heat storage cycle, and detecting means for detecting that the water is frozen during the heat storage cycle; Compressor control means for controlling the output of the compressor in response to the detection signal, and the compressor control means outputs the compressor output for all the heat storage cycles when water freezes during the heat storage cycle. Is a means for controlling the output of the compressor so that the output of the compressor with respect to the heat storage cycle in which the water has been frozen is subtracted. Excessive cooling in the production of can be prevented.

  If the detection means is a flow meter for detecting the flow rate of water in the heat storage cycle, the ice heat storage device is more effective in increasing detection accuracy when detecting freezing of water.

  The ice heat storage device of the present invention is an ice heat storage device having the refrigeration cycle and the heat storage cycle, and is provided between a condenser and a decompression means, and is supercooled from the refrigerant condensed in the condenser and the ice heat storage tank. A preheater for exchanging heat with water sent to the condenser, a cooling tower for cooling the cooling water, and a cooling water cycle having a cooling water pump for circulating the cooling water between the condenser and the cooling tower; The temperature control means for detecting the temperature of the cooling water for cooling the refrigerant, and the output control means for controlling the output of at least one of the power source for cooling and the compressor in the cooling water cycle, the output control means Is an output of at least one of the cooling power source and the compressor so that the temperature of the refrigerant in the condenser becomes a temperature within a predetermined range according to the temperature of the cooling water detected by the temperature detecting means. Control The predetermined range is equal to or higher than the temperature of the refrigerant in the condenser when the cooling water obtained during rated operation of the cooling power source is flowing during the cooling water cycle, and the temperature of the refrigerant in the condenser. Since it is below the set value, in the supercooled water type ice heat storage device, the amount of heat of the refrigerant used for preheating water before supercooling can be ensured even when the outside air temperature is low.

  In the ice heat storage device, the output control means outputs at least one of the cooling power source and the compressor so that the sum of the power consumption of the cooling power source and the power consumption of the compressor is minimized. It is even more effective to secure the amount of heat for preheating the water before the supercooling flowing through the heat storage cycle and to achieve high efficiency operation of the compressor and the cooling water pump. is there.

  When the cooling power source is the cooling water pump, the ice heat storage device is more effective in performing the operation for securing the amount of heat for preheating with high accuracy and simple control.

  When the supercooler is a plate-type heat exchanger, the ice heat storage device of the present invention is more effective in reducing pressure loss in the supercooler and performing stable operation of the ice heat storage device. In addition, with plate-type heat exchangers, it is usually not necessary to specify the location of water freezing in the subcooler, so it is easy to control the operation of the ice heat storage device related to detection of water freezing and release of this freezing. It is even more effective in achieving

  In the ice heat storage device of the present invention, the supercooling release device induces the release of the supercooling state of the supercooling release container in which the supercooling water is supplied and the supercooling water in the supercooling release container. A small ice storage device, further comprising a propagation preventer between the supercooler and the supercooler that prevents the propagation of ice from the supercooler to the supercooler. And more effective in performing stable ice heat storage operation.

  FIG. 1 shows an ice heat storage device according to an embodiment of the present invention. In FIG. 1, the configuration for performing the freeze release operation of the valves and heat exchangers around the supercooler is omitted.

  As shown in FIG. 1, the ice heat storage device of the present embodiment includes a refrigeration cycle that generates cold, a heat storage cycle that stores cold, a cooling water cycle that generates cold consumed in the refrigeration cycle, and a refrigeration cycle. And a heat transfer cycle for transferring cold energy from the heat storage cycle to the heat storage cycle.

  The refrigeration cycle includes a compressor 1 that compresses refrigerant vapor, a condenser 2 that cools and condenses the refrigerant compressed by the compressor 1, and a decompression that adiabatically expands the refrigerant condensed by the condenser 2. It has two expansion valves 3 and 4 as means, and an evaporator 5 for evaporating the refrigerant adiabatically expanded by the expansion valves 3 and 4. The compressor 1, the condenser 2, the expansion valve 4, and the evaporator 5 are connected by a refrigerant circulation channel 6 so that the refrigerant circulates through them. A preheater 7 is connected to the refrigerant circulation passage 6 between the condenser 2 and the expansion valve 4. A refrigerant circulation channel 6 that connects the condenser 2 and the preheater 7 and a refrigerant circulation channel 6 that connects the expansion valve 4 and the evaporator 5 are connected by a refrigerant bypass channel 8. The expansion valve 3 is provided in the refrigerant bypass passage 8. The compressor 1 has an inverter 9.

  The heat storage cycle is provided corresponding to each of the two subcoolers 11 and 12 for generating supercooled water and the respective subcoolers, and releases the supercooled state of the supercooled water to generate ice water. Are connected to each other so that the water circulates in two hermetic supercooling release units 13 and 14 for ice, an ice heat storage tank 15 that collectively stores ice water generated by the supercooling release units 13 and 14. A circulating water flow path 16, a circulating water pump 17 for circulating the water stored in the ice heat storage tank 15, and a part of the water in the circulating water flow path 16 are sent from the circulating water pump 17 to the preheater 7 to preheat. And a preheating circulation passage 18 for sending water sent to the vessel 7 to a circulation water passage 16 connecting the ice heat storage tank 15 and the circulation water pump 17. The subcoolers 11 and 12 are connected in parallel in the heat storage cycle.

  Between the supercoolers 11 and 12 and the supercool release devices 13 and 14, there are provided propagation preventers 19 and 20 for preventing the propagation of ice from the supercool release devices 13 and 14 to the supercoolers 11 and 12. It has been. The supercooling releasers 13 and 14 are provided with ultrasonic vibrators 21 and 22 for inducing the release of the supercooling state of the supercooling water. The circulating water channel 16 that connects the circulating water pump 17 and the subcooler 11 is provided with a flow meter 24b that detects the flow rate of water flowing through the channel. The circulating water channel 16 and the propagation preventer 19 are connected by a circulating water bypass channel 23, and the circulating water bypass channel 23 is provided with a flow meter 24a for detecting the flow rate of water flowing through the channel. It has been.

  Similarly, the circulating water flow path 16 that connects the circulating water pump 17 and the subcooler 12 is provided with a flow meter 26b that detects the flow rate of water flowing through this flow path. The circulating water passage 16 and the propagation preventer 20 are connected by a circulating water bypass passage 25, and the circulating water bypass passage 25 is provided with a flow meter 26a for detecting the flow rate of water flowing through the passage. It has been.

  In the cooling water cycle, the cooling water is circulated between the cooling tower 31 that cools the cooling water, the cooling water circulation passage 32 that connects the cooling tower 31 and the condenser 2, and the cooling tower 31 and the condenser 2. And a cooling water pump 33. The cooling tower 31 is provided with a cooling tower fan for air-cooling the cooling water. The cooling water pump 33 is provided with an inverter 34.

  The heat transfer cycle is performed between the evaporator 5 and the subcoolers 11 and 12, and between the evaporator 5 and the subcoolers 11 and 12. And a brine pump 42 for circulating the brine. The subcoolers 11 and 12 are connected in parallel in the brine circulation channel.

In addition, the ice heat storage device of the present embodiment further includes an operation control unit 50. The operation control unit 50 is a control unit having both the compressor control unit and the output control unit in the present invention, and is a unit that performs freezing determination around the subcooler in the heat storage cycle based on a signal from the flow meter. . The operation control unit 50 includes an inverter 9 of the compressor 1, flow meters 24a and 24b in the circulating water bypass passage 23 and the circulating water passage 16, flow meters 26a and 26b in the circulating water bypass passage 25 and the circulating water passage 16, And the inverter 34 of the cooling water pump 33 is connected so as to be able to send and receive electrical signals.

  The preheater 7 and the subcoolers 11 and 12 are plate heat exchangers. The plate heat exchanger forms a plurality of water channels by a structure in which a plurality of heat conductive plates are watertightly stacked with an appropriate interval. The plurality of flow paths are connected to each other to form two flow path groups, and the two flow path groups have a watertight structure. Heat exchange is performed by flowing a high-temperature fluid through one channel group and a low-temperature fluid through the other channel group, but it is arbitrary which channel group is allowed to flow a low-temperature or high-temperature liquid.

  As shown in FIGS. 2 and 3, the supercooling release unit 13 (14) includes a supercooling release container 13 a (14 a) having a substantially cylindrical shape and a supercooling water in the supercooling release container 13 a (14 a). Inlet part 13b (14b) for introducing water and outlet part 13c (14c) for discharging ice water from supercooling release container 13a (14a).

  The supercooling release container 13a (14a) has a substantially circular cross section. When this roughly circular shape is divided into four parts by dividing it into a circle, each of the two parts facing each other across the center is an arc of a quarter of the circumference, and each of the other two parts facing each other across the center. Are the two sides of the octagon. The inlet portion 13b (14b) is an upper portion of the supercooling release vessel 13a (14a) and is a portion of one of the arcs, and is provided at a position where supercooling water is introduced along the tangential direction of the arc. ing. The outlet portion 13c (14c) is a lower portion of the supercooling release vessel 13a (14a), and is provided at a position where the ice water is discharged along the tangential direction of the other arc. .

  As shown in FIG. 4, the propagation preventer 19 (20) has an outer periphery of the pipe 19a (20a) so as to form a sealed space on the outer peripheral surface side of the pipe 19a (20a) and the pipe 19a (20a). And an outer shell portion 19b (20b) covering the surface. On the peripheral wall of the tube 19a (20a) covered with the outer shell portion 19b (20b), a gap 19c (which connects the inside of the tube 19a (20a) and the space covered with the outer shell portion 19b (20b) over the entire periphery. 20c) is formed. A circulating water bypass passage 23 (25) is connected to the outer shell portion 19b (20b).

  Next, the ice heat storage operation of the ice heat storage device of the present embodiment will be described. First, an outline of the ice heat storage operation by the ice heat storage device of the present embodiment will be described.

  In the cooling water cycle, cooling water circulates between the condenser 2 and the cooling tower 31. Thus, the cooling water that has been heated by absorbing heat in the condenser 2 is cooled in the cooling tower 31, and the cooling water that has been cooled by releasing heat in the cooling tower 31 is sent to the condenser 2. The control of the cooling water pump 33 by the operation control unit 50 will be described in detail later.

  In the refrigeration cycle, the refrigerant compressed by the compressor 1 is cooled by the condenser 2 with cooling water and condensed. The condensed refrigerant may pass through the preheater 7 to the expansion valve 4 or may pass through the refrigerant bypass flow path 8 to the expansion valve 3. Here, the refrigerant passes through the preheater 7 and the expansion valve. The explanation will be made assuming that the number 4 is reached. The refrigerant condensed in the condenser 2 releases heat to circulating water described later in the preheater 7 and is adiabatically expanded by the expansion valve 4. The refrigerant adiabatically expanded by the expansion valve 4 evaporates in the evaporator 5 and takes heat from the brine. The refrigerant vapor is sent to the compressor 1. The control of the compressor 1 by the operation control unit 50 will be described in detail later.

  In the heat transfer cycle, brine circulates between the evaporator 5 and each of the subcoolers 11 and 12. Thereby, the brine cooled by releasing heat in the evaporator 5 is warmed by each of the subcoolers 11 and 12, and the brine heated by absorbing heat in each of the subcoolers 11 and 12 is evaporated. Sent to 5.

  In the heat storage cycle, water stored in the ice heat storage tank 15 is circulated by the circulating water pump 17. A part of the water supplied from the ice heat storage tank 15 is sent to the preheating circulation channel 18, preheated to about 10 ° C. by the preheater 7, and merges with the water supplied from the ice heat storage tank 15. By mixing part of the preheated circulating water and the circulating water sent from the ice heat storage tank 15, the temperature of the circulating water before supercooling is the temperature at which ice grains in the circulating water melt (for example, 0. 0. 5 ° C). The circulating water whose temperature has been adjusted in this way is sent to each of the subcoolers 11 and 12.

  A part of the circulating water sent to each of the subcoolers 11 and 12 is sent to each of the subcoolers 11 and 12, and the other part is sent to each of the circulating water bypass channels 23 and 25. . The circulating water sent to the subcoolers 11 and 12 is cooled by the brine in the subcoolers 11 and 12 and becomes, for example, −2 ° C. supercooled water. The supercooling water generated in each of the supercoolers 11 and 12 is sent to the pipes 19a and 20a of the propagation preventers 19 and 20 at an appropriate flow rate.

  On the other hand, the pipes 19a and 20a of the propagation preventers 19 and 20 are supplied with the temperature-controlled circulating water from the circulating water bypass channels 23 and 25 through the outer shell portions 19b and 20b and the gaps 19c and 20c, respectively. Supplied. In the flow direction of the supercooling water in the propagation preventers 19 and 20, the pipes 19a and 20a downstream from the gaps 19c and 20c have a layer of the circulating water whose temperature is adjusted on the inner peripheral surface side of the pipes 19a and 20a. A flow of the formed supercooling water is formed. The supercooling water flowing together with the circulating water layer is sent to the supercooling release units 13 and 14 at an appropriate flow rate.

  The supercooling water sent to the subcooler release units 13 and 14 spirally flows from the upper part to the lower part of the subcooler release containers 13a and 14a along the inner peripheral surfaces of the subcooler release containers 13a and 14a. . The supercooling water sent to the supercooling release units 13 and 14 is caused by the vibration caused by the ultrasonic vibrators 21 and 22 transmitted through the bottom and the peripheral wall portions of the supercooling release containers 13a and 14a, and the peripheral walls of the supercooling release containers 13a and 14a. The supercooled state is released by an impact or the like when flowing through the section, and becomes ice water.

  The moderate flow rate means that a temperature-regulated circulating water layer is formed on the inner peripheral surfaces of the pipes 19a and 20a in the pipes 19a and 20a downstream from the gaps 19c and 20c in the propagation preventers 19 and 20. It is a flow rate that allows supercooling water to flow spirally along the peripheral surfaces of the supercooling release containers 13a and 14a, and the efficiency of supercooling by the supercoolers 11 and 12, and the supercooling release containers 13a and 14a For example, the flow rate is such that the average flow velocity in the cross section of the pipe surrounded by the gaps 19c and 20c in the propagation preventers 19 and 20 is 1 m / s or more, depending on the shape, diameter, size, and the like. The diameters of the pipes 19a and 20a and the inlet portions 13a and 14a are set to appropriate diameters according to the refrigeration capacity of the refrigeration cycle and the capacity and form of the subcoolers 11 and 12 so as to realize the appropriate flow rate. Yes.

  The ice water generated by the supercooling release units 13 and 14 is sent to the ice heat storage tank 15, and sherbet-like ice is stored in the ice heat storage tank 15. Of the ice water sent to the ice heat storage tank 15, the water is sent again toward the preheater 7 and the subcoolers 11 and 12 by the circulating water pump 17.

  Next, in the ice heat storage device of the present embodiment, the operation when the circulating water is frozen in the heat storage cycle during the ice heat storage operation will be described. In such a case, the operation control unit 50 determines the freezing of the circulating water according to the detection signals of the flow meters 24a and 24b, 26a and 26b, and controls the output of the compressor 1. The reference for determining the occurrence of freezing of the circulating water from the detection signals of the flow meters 24a and 24b, 26a and 26b is not particularly limited, but in the present embodiment, per reference time in the circulating water bypass passages 23 and 25. Increase and decrease the flow rate of circulating water.

  More specifically, the operation control unit 50 receives a detection signal from the flow meter every predetermined time, for example, every 10 seconds, and determines whether the flow rate has increased or decreased based on whether the flow rate has increased or decreased by a predetermined amount. The predetermined amount for determining whether to increase or decrease the flow rate is not particularly limited. For example, when a flow meter with a resolution of 1% is used, it is about 1/100 of full scale. For example, when the flow rate of the flow meter 24a (26a) is increased and the flow rate of the flow meter 24b (26b) is decreased, the operation control unit 50 determines that the flow rate is increased or decreased.

  Note that when the flow rate of the flow meter 24a (26a) increases, the flow rate of the flow meter 24b (26b) increases, and when the flow rate of the flow meter 24a (26a) decreases, the flow rate of the flow meter 24b (26b) decreases. When it does, the operation control part 50 determines with the flow volume fluctuation | variation other than freezing. When the flow rate of the flow meter 24a (26a) decreases and the flow rate of the flow meter 24b (26b) increases, the operation control unit 50 determines that the circulating water bypass flow path 23 (25) is clogged.

  First, as shown in FIG. 8, the operation control unit 50 receives detection signals from the flow meters 24a and 24b, 26a and 26b, and determines the presence or absence of freezing (step 101). The operation control unit 50 checks the number of determinations of freezing of the circulating water (Steps 102 and 107).

  When the determination number is 1, the operation control unit 50 is a value obtained by subtracting the output of the compressor 1 for one subcooler from the output of the compressor 1 that has been operated for the total number of subcoolers. The control signal is sent to the inverter 9 of the compressor 1 so that the compressor 1 is operated at the output (50% output) (step 103).

  Next, the operation control unit 50 identifies the flow meter that has sent the detection signal that is the basis for the freezing determination, and identifies which subcooler or the surrounding water has been frozen (step 104). For example, if the flowmeters that have sent detection signals to notify freezing are the flowmeters 24a and 24b, the operation control unit 50 performs the freezing release operation with a valve or a heat exchanger (not shown) in the subcooler 11 and its surroundings. (Step 105). If the flowmeter that sent the detection signal notifying the freezing is not the flowmeters 24a and 24b, the operation control unit 50 similarly performs the freeze release operation in the subcooler 12 and its surroundings (step 106). Then, after a predetermined time, the operation control unit 50 receives the detection signals of the flow meters 24a and 24b, 26a and 26b again.

  When the determination number is two, the operation control unit 50 sends a control signal for stopping the operation of the compressor 1 to the inverter 9 (step 108), and as described above in the subcoolers 11 and 12 and the vicinity thereof. Freezing release operation is performed (step 109). After the freeze release operation, the operation control unit 50 sends a control signal for restarting the operation of the compressor 1 to the inverter 9 (step 110). Then, the operation control unit 50 receives the detection signals of the flow meters 24a and 24b, 26a and 26b again after a predetermined time.

  When the determination number is neither 1 nor 2, the operation control unit 50 receives the detection signals of the flow meters 24a and 24b, 26a and 26b again after a predetermined time.

  Next, in the ice heat storage device of the present embodiment, an operation for securing a preheat amount in the preheater 7 during the ice heat storage operation will be described. First, the operation that prioritizes securing the preheating amount in the preheater 7 during the ice heat storage operation will be described. Such an operation is performed by the operation control unit 50 controlling the outputs of the cooling water pump 33 and the compressor 1 so that the temperature of the refrigerant in the condenser is less than the set value.

  First, setting conditions in the operation for securing the preheating amount will be described.

Examples of the setting condition include a ratio of various power costs between the compressor 1 and a cooling power source. In the present embodiment, the cooling power source is the cooling water pump 33. In the present embodiment, the power consumption of the rated compressor 1 is 580 kW, the power consumption of the rated cooling water pump 33 is 102 kW, and the consumption of the rated compressor 1 and the rated cooling water pump 33. The ratio of electric power is 0.85 for the compressor 1 and 0.15 for the cooling water pump 33.

  Further, the condenser 2 sets an upper limit value of the temperature of the refrigerant and the temperature of the cooling water. From the viewpoint of protecting the compressor 1, the set value (upper limit value) of the refrigerant temperature in the condenser 2 is 40 ° C. Assuming that the temperature of the refrigerant in the condenser 2 at the rated operation of the cooling water pump 33 becomes the set value, the upper limit value of the temperature at the inlet of the cooling water condenser 2 obtained by the cooling water pump 33 at the rated time is 32. Let it be in ° C. When the cooling water pump 33 is operating under rated conditions, the temperature of the refrigerant in the condenser 2 changes in proportion to the temperature of the cooling water, that is, the temperature of the cooling water at the inlet of the condenser 2. These relationships are shown in FIG.

  Further, the relationship between the power consumption of the cooling water and the flow rate of the cooling water, and the heat transfer characteristics of the refrigerant from the cooling water in the condenser 2 are set. The power consumption of the cooling water pump 33 changes in proportion to the cube of the cooling water flow rate. Moreover, the heat transfer characteristic (overall heat transfer coefficient K) in the condenser 2 changes according to the flow rate of the cooling water. Therefore, the temperature difference (ΔT) between the cooling water and the refrigerant in the condenser 2 changes according to the flow rate of the cooling water. The ratio of the power consumption of the cooling water pump 33 to the cooling water flow rate (the rated time is 0.15) and ΔT ((coolant temperature) − (cooling water temperature)) with respect to the cooling water flow rate are as follows. It is shown in 1.

  On the other hand, in the ice heat storage operation, as described above, since the cooling load is constant, the evaporation temperature of the refrigerant in the evaporator 5 is constant, so that the power consumption of the compressor 1 is the power consumption of the refrigerant in the condenser 2. Varies with temperature. Such a relationship between the power consumption of the compressor 1 and the temperature of the refrigerant in the condenser 2 is obtained from a simulation of a refrigeration cycle, catalog data of the compressor 1 to be used, and the like. FIG. 6 shows the ratio of the refrigerant temperature in the condenser 2 to the power consumption of the compressor 1 (the ratio of the power consumption of the compressor 1 at the rated time is 0.85).

The case where the ice heat storage operation in which priority is given to securing the amount of preheating in the preheater 7 under the conditions set as described above will be described. The refrigerant temperature (lower limit) in the condenser depends on the design of the preheater, but here it is set to 32 ° C. in order to secure the preheat amount. As shown in FIG. 9, the operation control unit 50 receives a detection signal from a temperature sensor (not shown) that detects the temperature of the cooling water at the inlet of the condenser 2 (cooling water inlet temperature) (step 201). The operation control unit 50 that has received the detection signal from the temperature sensor has a sum of the cooling water inlet temperature and ΔT in the flow rate of the cooling water at that time, and 40 ° C., which is a set value of the refrigerant temperature in the condenser 2. Are examined in the order of less than 40 ° C. and more than 40 ° C. (steps 202 and 207).

  When the sum of the cooling water inlet temperature and ΔT is less than 40 ° C., the operation control unit 50 checks whether the sum of the cooling water inlet temperature and ΔT is 32 ° C. or more (step 203). If the sum of the cooling water inlet temperature and ΔT is 32 ° C. or more, the operation control unit 50 transmits a control signal for increasing the flow rate of the cooling water to a predetermined value (for example, 1%) to the inverter 34 of the cooling water pump 33. (Step 204). If the sum of the cooling water inlet temperature and ΔT is less than 32 ° C., the operation control unit 50 transmits a control signal for reducing the flow rate of the cooling water to a predetermined value (for example, 1%) to the inverter 34 of the cooling water pump 33. (Step 205). The operation control unit 50 that has transmitted the control signal to the inverter 34 newly obtains ΔT in the flow rate of the cooling water from the newly changed flow rate of the cooling water, and compresses at a sum of ΔT and the cooling water inlet temperature. The ratio of the power consumption of the machine 1 is obtained, and a signal for controlling the output of the compressor 1 is transmitted to the ratio to the inverter 9 of the compressor 1 (step 206). The operation control unit 50 that has transmitted the control signal returns to the step of receiving the detection signal from the temperature sensor.

  When the sum of the coolant inlet temperature and ΔT is 40 ° C. or higher, the operation control unit 50 checks whether the coolant flow rate is the maximum value, that is, whether the coolant pump 33 is operating under rated conditions ( Step 208). When the flow rate of the cooling water is not the maximum value, a control signal for increasing the flow rate of the cooling water by a predetermined value (larger than the aforementioned value, for example, 2%) is transmitted to the inverter 34 (step 209), and the temperature sensor Return to the step of receiving the detection signal from.

  When the flow rate of the cooling water is the maximum value, the operation control unit 50 continuously reaches the step of checking that the flow rate of the cooling water is the maximum value, and the number of times (n ) Is a predetermined number of times (for example, three times) or more (step 210). In the case where the number of times to reach the step is three or more times in succession, the operation control unit 50 closes the refrigerant bypass channel 8, increases the flow rate of circulating water in the preheating bypass channel 18, and supercools one of them. Other control means such as stopping the supply of circulating water to the vessel is instructed to other control means, or other control is performed (step 211).

  When the conclusion that the relationship between the sum of the cooling water inlet temperature and ΔT and 40 ° C. is not less than 40 ° C. and not 40 ° C. or more is obtained, the operation control unit 50 is 40 ° C. or more. It is checked whether or not the step of checking whether it is present is continuously reached and whether the number (n) of reaching this step is a predetermined number (for example, three times) or more (step 212). When the number of times to reach the step is three or more times in succession, the operation control unit 50 stops the operation of the compressor 1 and notifies the administrator of the stop of the operation of the compressor 1 (step 213). .

  Table 2 shows combinations of the cooling water inlet temperature and the cooling water flow rate for securing the preheating amount. In the control as described above, the temperature of the refrigerant in the condenser 2 is ensured to be 32 ° C. or higher, and the amount of preheating is ensured.

  Next, a description will be given of the case where the ice heat storage operation is performed in which the preheat amount in the preheater 7 is ensured and the energy saving operation is prioritized under the conditions set as described above.

  The operation control unit 50 receives a detection signal from a temperature sensor (not shown) that detects the temperature of the cooling water at the inlet of the condenser 2 (cooling water inlet temperature), similarly to the operation that prioritizes securing the preheat amount. The operation control unit 50 that has received the detection signal from the temperature sensor has a sum of the cooling water inlet temperature and ΔT in the flow rate of the cooling water at that time, and 40 ° C., which is a set value of the refrigerant temperature in the condenser 2. Are examined in the order of less than 40 ° C. and 40 ° C. or more.

  When the sum of the cooling water inlet temperature and ΔT is less than 40 ° C., the operation control unit 50 obtains an allowable cooling water flow range as shown in FIG. 10 (step 301). When the range of the flow rate of the cooling water is obtained, the operation control unit 50 obtains ΔT in the obtained flow rate of the cooling water, and the sum of the respective ΔT and the cooling water inlet temperature (the temperature of the refrigerant in the condenser). And the ratio of the power consumption of the compressor 1 in the allowable cooling water flow rate range is obtained (step 302). On the other hand, the operation control unit 50 obtains a range of power consumption of the cooling water pump 33 corresponding to the obtained flow rate range of the cooling water (step 303).

  If the ratio of the power consumption of the compressor 1 and the ratio of the power consumption of the cooling water pump 33 are obtained in accordance with the value of the flow rate of the cooling water, the operation control unit 50 corresponds to the value of the flow rate of the cooling water. The sum of the power consumption ratio of the compressor 1 and the power consumption ratio of the cooling water pump 33 is obtained (step 304). Then, the operation control unit 50 selects a combination of the ratio of the power consumption of the compressor 1 and the ratio of the power consumption of the cooling water pump 33 that makes the sum the smallest value in the obtained flow range of the cooling water. And the signal which controls the output of the cooling water pump 33 to the ratio of the power consumption of the selected cooling water pump 33 is transmitted to the inverter 34 (step 305). The operation control unit 50 that has transmitted this signal confirms that the compressor 1 is operating at the power consumption rate of the selected compressor 1 (step 306). The operation control unit 50 returns to the step of receiving the detection signal from the temperature sensor.

For the subsequent steps when the sum of the cooling water inlet temperature and ΔT is 40 ° C. or higher, the preheater 7
This is the same as the operation that prioritizes securing the amount of preheating.

  FIG. 7 and Table 3 show the relationship between the cooling water inlet temperature and the sum of the power consumption ratios of the compressor 1 and the cooling water pump 33, which are obtained when such priority is given to energy saving operation. In FIG. 7 and Table 3, the minimum value of the sum of the power consumption ratios of the compressor 1 and the cooling water pump 33 is not determined when the flow rate of the cooling water is a predetermined ratio. It is shown that it depends on the combination with the flow rate of water.

  FIG. 5 shows the relationship between the combination of the cooling water inlet temperature and the cooling water flow rate at which the minimum value is obtained, and the refrigerant temperature in the condenser 2. As shown in FIG. 5, according to the control described above, when the cooling water inlet temperature is 27 ° C. or lower, the temperature of the refrigerant in the condenser 2 is higher by 4 ° C. or more than when the cooling water pump is operated under rated conditions. Become.

  The numerical values obtained when the above-described control is performed are shown in Table 4 below, taking the case where the cooling water inlet temperature is 28 ° C. as an example. As is clear from Table 4, when the cooling water inlet temperature is 28 ° C., 0.801 is selected as the power consumption ratio of the compressor 1 and 0.051 as the power consumption ratio of the cooling water pump 33. Is selected.

  The temperature of the cooling water decreases as the outside air temperature decreases. If the refrigeration capacity is constant and the flow rate of the cooling water is constant as in the ice heat storage operation, the refrigerant temperature and the preheating amount in the condenser 2 are as shown in FIG. Decrease due to decrease in

  In the operation that prioritizes securing the amount of preheat in the preheater 7, the operation of the ice heat storage device is controlled in a direction that reduces the output of the cooling water pump 33 within an allowable range. Even when the outside air temperature is low, “outside air temperature: high” in FIG.

  In the operation that secures the amount of preheating in the preheater 7 and prioritizes the energy saving operation, the output of the cooling water pump 33 is reduced within an allowable range, but there is an increase in the output of the compressor 1 associated therewith. Since the operation of the ice heat storage device is controlled so that the sum of the outputs of the compressor 1 and the cooling water pump 33 is minimized at the outside air temperature, the refrigeration cycle during this operation is performed even when the outside air temperature is low, as shown in FIG. It is usually expressed in the form of "outside temperature: medium" or close to it.

  In addition, since the ice thermal storage apparatus in this Embodiment has the expansion valves 3 and 4 and the refrigerant | coolant bypass flow path 8, the flow volume of the refrigerant | coolant which passes the preheater 7 by adjusting the opening degree of the expansion valves 3 and 4 Can be adjusted. This makes it possible to adjust the temperature of the circulating water in the heat storage cycle, the temperature of the refrigerant after condensation (before adiabatic expansion), and the like.

  In addition, the ice heat storage device in the present embodiment can be variously modified as long as the ice heat storage operation in the present embodiment is not hindered. For example, in the ice heat storage device in the present embodiment, if a valve for adjusting the flow rate of the circulating water is provided in the preheating circulation channel 18, the temperature of the circulating water before the supercooling in the heat storage cycle can be adjusted. When the outside air temperature is high, the cooling water temperature is high, and the preheat amount of the refrigerant in the preheater 7 is too large, the flow rate of the preheated circulating water is controlled and the temperature of the circulating water is appropriately controlled. It becomes possible.

  Further, in the ice heat storage device in the present embodiment, when a flow meter is provided in each of the circulating water passages 16 on the upstream side of the subcoolers 11 and 12, the flow meters 24 for the flow rates detected by these flow meters, It is possible to detect the amount of change in the flow rate detected at 26, and it is possible to further increase the accuracy of detecting the freezing of the circulating water in the heat storage cycle.

  In the present embodiment, the cooling power source is the cooling water pump 33. However, the cooling power source is provided in the cooling tower 31 or the cooling power source. The power source may be the cooling water pump 33 and the cooling tower fan. In such a case, the ratio of the output of the cooling tower fan at the rated time is set, and the relationship between the output of the cooling tower fan in the cooling tower 31 and the temperature of the cooling water at that time is obtained by actual measurement or simulation. This result may be reflected in the cooling water inlet temperature.

  In the present embodiment, the control by the operation control unit 50 shows only the control form as the compressor control means and the output control means, but the operation control part 50 is limited to this form. Instead, the configuration shown in the present embodiment such as the expansion valves 3 and 4 and the circulating water pump 17 may be further controlled, and may be added by various appropriate modifications described above. Further control of other configurations may be performed. In such a case, the valve is preferably an automatic valve, and an inverter is preferably used for output control.

  Moreover, in this Embodiment, although the form which detects the freezing of the water around a supercooler with a flowmeter was shown, it replaced with a flowmeter and each of the inlet side of the subcoolers 11 and 12 and an exit side is shown. Even if a pressure gauge is provided in the circulating water flow path 16, it is possible to detect water freezing around the subcooler. In such a configuration, when the pressure gauge on the inlet side of the subcooler is A and the pressure gauge on the outlet side is B, the operation control unit 50 increases the pressure of the pressure gauge A and the pressure of the pressure gauge B. Is determined to be frozen.

  Note that when the pressure of the pressure gauge A increases and the pressure of the pressure gauge B increases, and when the pressure of the pressure gauge A decreases and the pressure of the pressure gauge B decreases, the operation control unit 50 is not frozen. It is determined that there is a pressure fluctuation. In addition, when the pressure of the pressure gauge A decreases and the pressure of the pressure gauge B increases, the operation control unit 50 determines that the pressure gauge is abnormal or backflow. The interval at which the operation control unit 50 receives the detection signal from the pressure gauge and the criteria for determining the pressure increase / decrease may be appropriately set according to the type of the pressure gauge.

  According to the ice heat storage device of the present embodiment, a plurality of heat storage cycles in which the plurality of supercoolers 11 and 12 are connected in parallel, the circulating water bypass passages 23 and 25, and the flow meters 24a and 24b and 26a. 24b and the operation control unit 50, it is possible to detect the freezing of water flowing through each heat storage cycle, and when the water freezing is detected, the heat storage in which the water has been frozen is detected. Since the output of the compressor 1 is controlled by the value obtained by subtracting the output of the compressor 1 with respect to the cycle, excessive cooling in the generation of supercooling water can be prevented.

  Moreover, according to the ice heat storage apparatus of this Embodiment, since it has the compressor 1 and the inverter 9, the cooling water pump 33 and the inverter 34, the operation control part 50, and the preheater 7, according to external temperature. By controlling the flow rate of the cooling water and the output of the compressor 1 associated therewith, the temperature of the refrigerant in the condenser 2 is maintained at a high temperature, and the predetermined preheating heat quantity of the circulating water flowing in the heat storage cycle is maintained. Therefore, even when the outside air temperature is low, the heat quantity of the refrigerant used for preheating water before supercooling can be ensured.

  In addition, the ice heat storage device of the present embodiment includes the inverter 9 and the inverter 34, and can perform the energy saving priority operation under the condition of securing the preheating amount. In the apparatus, the operation for securing the preheating amount can be performed with the smallest output that can secure the preheating amount of the circulating water in the heat storage cycle.

Further, since the ice heat storage device of the present embodiment has the sealed supercooler releasers 13 and 14 as the subcooler releaser, it is more supercooled than when the open type supercooler releaser is provided. Since the space required for installing the releaser can be reduced, the ice heat storage device can be reduced in size.

  In addition, since the ice heat storage device of the present embodiment includes the propagation preventers 19 and 20, propagation of the release of the supercooling state to the subcooler is prevented, so that the water flowing through the heat storage cycle can be frozen. And stable ice storage operation can be performed.

  In addition, since the ice heat storage device of the present embodiment has the plate-type supercoolers 11 and 12 as the supercooler, compared with the case of having the shell-and-tube type supercooler, the circulating water or brine Pressure loss due to liquid flow can be reduced. Further, since partial freezing of water in the subcoolers 11 and 12 does not occur, detection of freezing and control of the release thereof can be facilitated.

It is a figure which shows the structure of the ice thermal storage apparatus of one Embodiment of this invention. It is a front view of the supercooling release devices 13 and 14 used with the ice thermal storage apparatus shown by FIG. It is a cross-sectional view of the subcool releasers 13 and 14 shown in FIG. It is a longitudinal cross-sectional view of the propagation preventers 19 and 20 used with the ice thermal storage apparatus shown by FIG. The temperature of the cooling water at the inlet of the condenser 2 during the rated operation of the cooling water pump 33 of the ice heat storage device shown in FIG. 1 and the energy saving operation for ensuring the preheat amount of circulating water in the heat storage cycle, and the condenser 2 It is a graph which shows the relationship with the temperature of the refrigerant | coolant in. It is a graph which shows the relationship between the temperature of the refrigerant | coolant in the condenser 2, and the ratio of the power consumption of the compressor 1. FIG. The sum of the temperature of the cooling water at the inlet of the condenser 2 and the ratio of the power consumption of the compressor 1 and the cooling water pump 33 under the operating conditions below the rated operation of the cooling water pump 33 of the ice heat storage device shown in FIG. And the minimum value of the sum of the ratios of the power consumption with respect to the temperature of the cooling water at the inlet of the condenser 2. It is a flowchart which shows an example of control of the driving | operation of the said ice thermal storage apparatus when freezing of water arises in the thermal storage cycle of the ice thermal storage apparatus shown by FIG. 2 is a flowchart showing an example of control of operation of the ice heat storage device giving priority to securing heat for circulating water preheating in the preheater 7 in the ice heat storage device shown in FIG. 1. FIG. 2 is a flowchart showing an example of operation control of the ice heat storage device that secures heat for preheating circulating water in the preheater 7 and prioritizes energy saving operation in the ice heat storage device shown in FIG. 1. It is a Mollier diagram which shows the refrigerating cycle of a normal ice thermal storage apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Condenser 3, 4 Expansion valve 5 Evaporator 6 Refrigerant circulation flow path 7 Preheater 8 Refrigerant bypass flow path 9, 34 Inverter 11, 12 Subcooler 13, 14 Subcooler releaser 13a, 14a Subcooler release Container 13b, 14b Inlet part 13c, 14c Outlet part 15 Ice heat storage tank 16 Circulating water channel 17 Circulating water pump 18 Preheating circulating channel 19, 20 Propagation preventers 19a, 20a Pipes 19b, 20b Outer shell parts 19c, 20c Clearance 21 , 22 Ultrasonic vibrators 23, 25 Circulating water bypass channels 24a, 24b, 26a, 26b Flow meter 31 Cooling tower 32 Cooling water circulating channel 33 Cooling water pump 41 Brine circulating channel 42 Brine pump 50 Operation control unit

Claims (5)

A refrigeration cycle that generates cold by compression, condensation, expansion, and evaporation of the refrigerant, and a heat storage cycle that stores the cold generated by the refrigeration cycle,
The refrigeration cycle includes a compressor for compressing refrigerant vapor, a condenser for cooling and condensing the refrigerant compressed by the compressor with cooling water, and a decompression means for adiabatically expanding the refrigerant condensed by the condenser. And an evaporator for evaporating the refrigerant adiabatically expanded by the decompression means,
The heat storage cycle includes: a supercooler that generates supercooled water by subcooling water to 0 ° C. or less by cold heat generated by the evaporator of the refrigeration cycle; and an excessive amount of supercooled water generated by the subcooler. In an ice heat storage device having a supercooling release unit that releases iced water by releasing the cooling state, and an ice heat storage tank that stores ice water generated by the supercooling release unit,
A plurality of the heat storage cycles, a detection means for detecting that water has frozen during the heat storage cycle, and a compressor control means for controlling the output of the compressor in accordance with a detection signal from the detection means. Have
The compressor control means is a value obtained by subtracting the output of the compressor for the heat storage cycle in which water has been frozen from the output of the compressor for all the heat storage cycles when water is frozen during the heat storage cycle. An ice heat storage device characterized by being a means for controlling the output of the compressor.   The detection means is selected from the group consisting of a flow meter that detects the flow rate of the water in the heat storage cycle, a flowmeter that indirectly detects the flow rate of the water, and a pressure meter that detects the pressure of the water. The ice heat storage device according to claim 1, wherein there are two or more. A refrigeration cycle that generates cold by compression, condensation, expansion, and evaporation of the refrigerant, and a heat storage cycle that stores the cold generated by the refrigeration cycle,
The refrigeration cycle includes a compressor for compressing refrigerant vapor, a condenser for cooling and condensing the refrigerant compressed by the compressor with cooling water, and a decompression means for adiabatically expanding the refrigerant condensed by the condenser. And an evaporator for evaporating the refrigerant adiabatically expanded by the decompression means,
The heat storage cycle includes: a supercooler that generates supercooled water by subcooling water to 0 ° C. or less by cold heat generated by the evaporator of the refrigeration cycle; and an excessive amount of supercooled water generated by the subcooler. In an ice heat storage device having a supercooling release unit that releases iced water by releasing the cooling state, and an ice heat storage tank that stores ice water generated by the supercooling release unit,
A preheater that is provided between the condenser and the pressure reducing means and performs heat exchange between the refrigerant condensed in the condenser and the water sent from the ice heat storage tank of the heat storage cycle to the supercooler;
A cooling water cycle having a cooling tower for cooling the cooling water, and a cooling water pump for circulating the cooling water between the condenser and the cooling tower;
Temperature detecting means for detecting the temperature of cooling water for cooling the refrigerant;
An output control means for controlling the output of at least one of the power source for cooling and the compressor in the cooling water cycle;
The output control means is a power source for cooling such that the temperature of the refrigerant in the condenser is a temperature within a predetermined range according to the temperature of the cooling water detected by the temperature detecting means. And means for controlling the output of at least one of the compressors,
The predetermined range is equal to or higher than the temperature of the refrigerant in the condenser when the cooling water obtained during rated operation of the power source for cooling flows in the cooling water cycle, and the set value of the temperature of the refrigerant in the condenser An ice heat storage device characterized by the following.   The output control means outputs the output of at least one of the cooling power source and the compressor so that the sum of the power consumption of the cooling power source and the power consumption of the compressor is minimized. 4. The ice heat storage device according to claim 3, wherein the ice heat storage device is a control means.   The ice heat storage device according to claim 3 or 4, wherein the cooling power source is the cooling water pump.

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