KR20100114296A - Apparatus for refrigeration cycle using ice thermal storage and showcase including the apparatus and control method for the same - Google Patents

Abstract

PURPOSE: A refrigeration cycle using the ice storage, an ice storage showcase apparatus including the same and a method of controlling the operation of the showcase apparatus are provided to enable the energy to be efficiently used through the restriction of the peak load of summer daytime. CONSTITUTION: A refrigeration cycle using the ice storage comprises an ice-storing refrigerant line, an ice-making heat exchanger, an ice-making expansion valve, a super-cooling refrigerant line, a super-cooling heat exchanger, and an ice storage tank. The ice-storing refrigerant line is separately installed in order to connect a condenser to a compressor. The ice-making heat exchanger is installed on the ice-storing refrigerant line. The ice-making expansion valve is installed on the front of the ice-making heat exchanger of the ice-storing refrigerant line. The super-cooling refrigerant line is separately installed in order to connect the condenser to the expansion valve. The super-cooling heat exchanger is installed on the super-cooling refrigerant line. The ice storage tank holds the ice-making heat exchanger and the super-cooling heat exchanger and is filled with the heat medium.

Description

Refrigeration cycle device using ice heat storage, refrigerated showcase device having same and its operation control method {APPARATUS FOR REFRIGERATION CYCLE USING ICE THERMAL STORAGE AND SHOWCASE INCLUDING THE APPARATUS AND CONTROL METHOD FOR THE SAME}

The present invention relates to a cold storage showcase device and the like, and more particularly, to reduce the peak load during the summer day, to contribute to the efficient use of energy and to equalize the national power load, as well as to save energy and reduce equipment costs. The operation method, and a refrigeration cycle apparatus and its operation control method applied to the same.

In general, the showcase cools the inside of the showcase by a phase change and heat exchange according to the evaporation and compression of the refrigerant, as in a general refrigerator. The process in which the refrigerant repeatedly evaporates (gases) and liquefaction is called a refrigeration cycle, the operation principle of the showcase is also caused by this refrigeration cycle.

Referring to FIG. 1, in a refrigerator unit, a refrigerant having a large latent heat of evaporation is compressed in a compressor to be discharged at a high temperature and high pressure, and is sent to a condenser to release a heat into the atmosphere to make a high pressure liquid. The high pressure liquid is dehydrated and sent to an expansion valve to control the cooling effect.

Subsequently, the gaseous refrigerant that is expanded while passing through the expansion valve passes through the evaporator in the showcase in a low-temperature, low-pressure gas state, where heat is exchanged with the outside air of the evaporator by a fan (FAN) attached to the heat exchanger. The cold air cooled by the action flows along the cold air flow path and is discharged downward from the top to block the open front surface of the showcase to form an air curtain.

Cold air is discharged from the upper part of the front of the showcase to the bottom by the operation of the refrigeration cycle, thereby forming an air curtain, thereby separating the cooling state by blocking heat penetration outside the showcase. It is the principle of operation.

On the other hand, show-cases, which are generally used for the storage or display of foods that require refrigeration / freezing in convenience stores or supermarkets, have a high operating cost to maintain a low temperature of about -20 to 8 ° C throughout the year. It is an energy-saving cold heat device. The cooling of the showcase is performed by a refrigerator using an electric drive compressor installed together to produce a low temperature refrigerant (freon), and to supply the produced low temperature refrigerant to a heat exchanger installed inside the showcase.

At home and abroad, the use of showcases is gradually increasing due to the increase in convenience stores and medium and large supermarkets. In addition, the showcase has a relatively short lifespan of about seven years, so the demand is very stable. The use of these showcases is not only an increase in electrical energy consumption, but also one of the important factors that undermine the national energy load leveling by deepening the peak load during the summer season.

According to data from Japan, medium and large supermarkets account for about 60% of the total energy costs for cooling showcases, which is much larger than the 15% used for air conditioning and 25% for other lighting. Accounted for.

Accordingly, as a method for improving the energy use efficiency of the showcase and reducing the weekly power consumption, many researches and developments on the improvement of the operation efficiency of the refrigerator and the improvement of the refrigerant distribution method have been conducted, but until now, the weekly power consumption of the showcase has not been effectively reduced. I can't.

That is, until now, in refrigerators such as showcases, peak loads during summer season can be suppressed to contribute to the efficient use of energy and to equalize the national power load, to reduce the capacity of the freezer, and to save energy and reduce equipment costs. Cooling cycle system is not being applied.

The present invention is to solve the above problems, by using the ice heat storage system for cooling the showcase, to suppress the peak load during the summer day to contribute to the efficient use of energy and the national power load leveling, The purpose is to reduce energy consumption and reduce equipment costs.

That is, the present invention produces and stores ice in the ice storage tank during the late night time, and applies the method of supercooling the refrigerant flowing into the heat exchanger in the showcase using the cold heat stored in the ice storage tank during the daytime when the cooling load is high. The purpose of the present invention is to provide a refrigerating cycle using ice heat storage, a cold storage showcase having the same, and a method of controlling the operation thereof, which can be reduced and contribute to efficient cooling as well as leveling of power load.

In order to achieve the above object, the present invention is a refrigeration cycle provided with a compressor, a condenser, an expansion valve and an evaporator on the refrigerant line, the refrigerant line for the ice shaft separately installed to connect the condenser and the compressor; An ice making heat exchanger installed on the ice storage refrigerant line; An ice making expansion valve installed in front of the ice making heat exchanger of the ice storage refrigerant line; A supercooling refrigerant line installed separately to connect the condenser and the expansion valve; A subcooling heat exchanger installed on the subcooling refrigerant line; The ice storage heat exchanger and the subcooling heat exchanger is accommodated and the ice heat storage tank is filled with a heat medium therein is provided a refrigeration cycle apparatus using the ice storage heat.

The refrigeration cycle apparatus of the above-described configuration includes a connection point between the refrigerant line connecting the condenser and the evaporator, the refrigerant line for the ice making line, the refrigerant line connecting the condenser and the evaporator, and an inlet side line of the supercooling refrigerant line; At the connection point of the connection point between the refrigerant line connecting the condenser and the evaporator and the outlet line of the subcooling refrigerant line, and the connection point between the refrigerant line and the ice making refrigerant line connecting the evaporator and the compressor. , The three-way valve for adjusting the flow direction of the refrigerant is characterized in that it is installed.

On the other hand, according to the method of the present invention for achieving the above object, in the operation of the refrigerating cycle apparatus of the above-described configuration, in order to cool the heat medium accommodated in the ice storage tank, the refrigerant to the ice making heat exchanger side accommodated in the ice storage tank. There is provided an operation control method of a refrigeration cycle apparatus using ice heat storage, characterized in that to cool the heat medium in the ice heat storage tank by circulating.

On the other hand, according to another aspect of the method of the present invention for achieving the above object, in the operation of the refrigeration cycle apparatus of the above-described configuration, in the case of using the ice storage heat of the cooled heat medium, part or all of the refrigerant passing through the condenser Provided is an operation control method of a refrigeration cycle apparatus using an ice storage heat, characterized in that the flow through the subcooling heat exchanger accommodated in the ice storage tank to flow into the evaporator.

On the other hand, according to another aspect of the present invention for achieving the above object, the present invention is a compressor and condenser, expansion valve and evaporator which is provided to configure a refrigeration cycle on the refrigerant line; Refrigerant line for ice shaft is installed separately to connect the condenser and the compressor; An ice making heat exchanger installed on the ice storage refrigerant line; An ice making expansion valve installed in front of the ice making heat exchanger of the ice storage refrigerant line; A supercooling refrigerant line installed separately to connect the condenser and the expansion valve; A subcooling heat exchanger installed on the subcooling refrigerant line; The ice storage heat exchanger and the subcooling heat exchanger is accommodated and the heat storage tank is filled with a heat medium therein; is provided with a heat storage showcase having a refrigeration cycle device using the ice heat storage.

At this time, the connection point between the refrigerant line connecting between the condenser and the evaporator and the refrigerant line for ice making, the connection point between the refrigerant line connecting between the condenser and the evaporator and the inlet line of the supercooling refrigerant line, and the condenser The flow direction of the refrigerant is controlled at the connection point between the refrigerant line connecting the evaporator and the outlet line of the subcooling refrigerant line, and the connection point between the refrigerant line connecting the evaporator and the compressor and the ice making refrigerant line. It is characterized in that the three-way valve is installed.

On the other hand, according to another aspect of the method of the present invention for achieving the above object, in the operation control method of the heat storage showcase, the refrigerant passing through the compressor and the condenser circulates the showcase in the late-night time when the ice storage heat storage tank is unnecessary Provided is an operation control method for a heat storage showcase, characterized in that ice is produced and stored in an ice storage tank by circulating a refrigerant to an ice making heat exchanger side.

In addition, according to another aspect of the method of the present invention for achieving the above object, in the operation control method of the heat storage showcase, the showcase after passing a part or all of the refrigerant passing through the condenser in the daytime time through the supercooling heat exchanger accommodated in the ice storage tank Provided is a driving control method of a heat storage showcase, characterized in that to be introduced into.

The effects of the present invention are as follows.

First, the present invention not only contributes to the efficient use of energy and leveling the national power load by suppressing peak loads during the summer season, but also reduces the capacity of the refrigeration equipment, thereby saving energy and reducing the cost of power receiving facilities. Can be provided.

In addition, the present invention by using the ice heat storage system for cooling the showcase to suppress the peak load during the summer day due to the use of the showcase not only contribute to the efficient use of energy and national power load leveling, but also to reduce the capacity of the freezer Energy saving and facility cost reduction effect can also be obtained.

That is, the present invention produces and stores ice in the ice storage tank during the late night time, and applies the method of supercooling the refrigerant flowing into the heat exchanger in the showcase using the cold heat stored in the ice storage tank during the daytime when the cooling load is high. It can reduce and contribute to efficient cooling as well as leveling the power load.

In addition, unlike the existing heat storage system that can be used only in summer, the heat storage showcase of the present invention is applicable to other seasons, and does not use the heat medium directly for freezing to operate the freezer by supercooling the refrigerant passing through the heat medium. Because of the structure, there is an effect that can easily secure the storage space of the heat storage tank installation.

In addition, the present invention does not simply connect the ice storage system and the showcase in parallel, but by operating the ice storage system and the showcase in a completely different operation method at night and daytime, without giving the consumer the inconvenience caused by the degradation of the thermal performance of the showcase. It has the effect of improving the coefficient of performance.

In addition, the present invention can expand the possibility of expanding the development of a new showcase system applying a variety of energy-saving technologies.

In other words, the present invention contributes to the reduction of summer power peak and leveling of power load by spreading the ice heat storage system, and to reducing the power receiving facilities and reducing peak power by transferring the daytime load of the showcase to the late night time.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 2 to 5.

Prior to the description of each embodiment of the present invention, the ice storage tank in the present invention was used as a heat storage tank using water having the largest heat capacity as a representative of the heat medium, but the heat medium for heat storage is not necessarily limited to water, so ethylene glycol Or brine is assumed to have a comprehensive meaning including a heat medium with a large heat capacity.

Example 1

Figure 2 is a system configuration of a refrigerated showcase is applied to the refrigeration cycle device using the ice storage heat storage of the present invention, the heat storage showcase system of the present invention is added to the existing non-heat storage showcase refrigeration system ice-on-coil ice storage tank (ice-on-coil) It is a refrigeration system employing a method of producing and storing ice in an ice storage tank during the late night time, and then supercooling the refrigerant flowing into the heat exchanger in the showcase using the cold heat stored in the ice storage tank during the daytime when the cooling load is high.

Specifically, the heat storage showcase system of the present invention includes a compressor for compressing and discharging a refrigerant, a condenser for condensing the refrigerant discharged from the compressor, an expansion valve connected to the condenser and expanding the refrigerant, and a connection to the expansion valve. An evaporator and a refrigerant line connecting the compressor, the condenser, the expansion valve, and the evaporator, an ice storage refrigerant line separately installed to connect the condenser and the compressor, and an ice making heat exchanger installed on the ice storage refrigerant line. Roof tile, an ice making expansion valve installed in front of the ice making heat exchanger of the ice storage refrigerant line, a subcooling refrigerant line separately installed to connect the condenser and the expansion valve, and a subcooling installed on the subcooling refrigerant line A heat exchanger, the ice making heat exchanger and a subcooling heat exchanger are accommodated, and a heat medium is filled therein. It is configured to further include an ice thermal storage tank.

At this time, the refrigerant flows at the connection point between the refrigerant line connecting the condenser and the evaporator and the refrigerant line for ice making, and the connection point between the refrigerant line connecting the condenser and the evaporator and the inlet line of the supercooling refrigerant line. Three-way valve is installed to adjust the direction.

In addition, the refrigerant flows at the connection point between the refrigerant line connecting the condenser and the evaporator and the outlet line of the subcooling refrigerant line, and the connection point between the refrigerant line and the ice making refrigerant line connecting the evaporator and the compressor. Three-way valve is installed to adjust the direction.

The showcase, on the other hand, is a plug-in type with one refrigerator attached to the bottom of the unit showcase, and several showcases (usually 3-7 depending on the capacity of the showcase) are connected together in one medium or large refrigerator. There is a remote type, and the present invention is also applicable to an integrated type in which a refrigerator is attached to the lower part of the unit showcase, and in particular, a remote type showcase system is mainly applied.

The operation and action of the heat storage showcase of the present invention configured as described above are as follows.

First, the operation of a general showcase is a cycle in which the refrigerant passing through the compressor and the condenser passes through the expansion valve and the evaporator, and the showcase is caused by forced circulation of cold air generated by heat exchange between the refrigerant passing through the evaporator and the air. Cooling takes place.

That is, the refrigerant having a large latent heat of evaporation is compressed in a compressor and sent to the condenser in a state of high temperature and high pressure, and the condenser releases heat into the atmosphere to make the refrigerant into a high pressure liquid state, and the refrigerant in the high pressure liquid state is dehydrated and has a cooling effect. It is sent to a capillary tube that can be adjusted.

Subsequently, the gaseous refrigerant expanded while passing through the expansion valve passes through the evaporator in the showcase in a low-temperature low-pressure gas state, and the cold air cooled by heat exchange with the refrigerant passing through the evaporator flows along the cold air flow path of the showcase. In order to block the open front surface of the showcase is discharged from the top to form an air curtain (Air-Curtain).

This general showcase operation is performed when the temperature of the showcase is not a temperature at which the ice storage heat is available, even in an operation mode in which the ice storage system is not used or an operation mode in which the ice storage system is used.

That is, when the ice storage system is not used because it is not a late night time, or even when the showcase storage room temperature does not reach a desired temperature even in the late night time, general operation is performed.

On the other hand, in the case of using the ice storage system to cool the heat medium contained in the ice heat storage tank, the heat medium in the ice heat storage tank is cooled by circulating a refrigerant to the ice making heat exchanger side accommodated in the ice heat storage tank. That is, referring to FIG. 3A, during a late night time, refrigerant passing through a compressor and a condenser circulates through a showcase, and when the showcase cooling is unnecessary, ice is circulated in the ice storage tank by circulating the refrigerant to an ice making heat exchanger housed in the ice storage tank. (See arrow direction indicated by the dotted line in FIG. 3A).

In the above, the temperature sensing of the showcase and the change of the refrigerant circulation path are automatically controlled by a non-shown temperature sensor and controller and a three-way valve controlled by the controller.

On the other hand, when the ice storage heat of the heat medium cooled by the above-described ice storage system is to be used for subcooling of the refrigerant, part or all of the refrigerant passing through the condenser passes through the subcooling heat exchanger accommodated in the ice storage tank, and then flows into the evaporator. That is, referring to FIG. 3B, during the daytime, some or all of the refrigerant passing through the condenser passes through the subcooling heat exchanger accommodated in the ice storage tank, and then flows into the showcase (see arrow direction indicated by the dotted line in FIG. 3B).

Since the temperature of the refrigerant passing through the condenser is about 40 ° C., heat is generated when passing through the ice storage tank, and this heat melts the ice iced at the upper end of the ice storage tank, thereby passing the ice storage tank. This is because the supercooled coolant flows into the showcase and cools the showcase more efficiently than the method of not supercooling the coolant. In this case, the refrigerant flowing into the showcase means that the refrigerant flows into the showcase side evaporator.

3A and 3B illustrate a case in which one showcase is provided, but in the case of a remote type in which several showcases are connected to one medium or large freezer according to the principle described above. The showcase is driven.

That is, during the late-night hours, the refrigerant passing through the compressor and the condenser passes through several showcases. If the temperature of the particular showcase falls below the desired temperature, the refrigerant does not have to flow toward the specific showcase, and the cooling power is not sufficient. Therefore, it is possible to produce and store ice in the ice storage tank by circulating the refrigerant to the ice making heat exchanger side accommodated in the ice storage tank.

In the multiple showcase system, even if one of the showcases connected to the freezer does not reach a desired temperature, ice may be produced and stored in the ice storage tank by circulating a refrigerant to an ice making heat exchanger housed in the ice storage tank. Of course.

Meanwhile, in the remote type showcase system, a part or all of the refrigerant passing through the condenser is selectively introduced into each showcase after passing through the subcooling heat exchanger accommodated in the ice storage tank during the daytime period.

At this time, when the temperature of a particular showcase of the several showcases falls below a desired temperature, the supercooled refrigerant passing through the subcooling heat exchanger is controlled so that the refrigerant does not flow.

Figure 4 is a graph showing the operating state of the conventional refrigeration system and the conventional non-refrigeration system of the present invention, looking at the graph, it can be seen that the transfer of the load was made by using the storage system of the present invention.

In other words, the power consumption of the refrigerated noodle showcase with a large day-time load can be transferred to the night time, so that when the consumer adopts the heat storage system of the present invention, it is possible to use a cheap night power, which is about 40% of the general electric bill It can be seen that the operation cost for cooling can be greatly reduced.

Example 2

Hereinafter, a second embodiment of the present invention will be described with reference to FIG. 5.

5 is a configuration diagram of a cold storage showcase system according to another embodiment of the present invention, in which the showcase device of the present embodiment employs an inverter compressor including the above-described inverter controller, and the rest of the configuration is the same as in the above-described embodiment. Do.

According to this embodiment configured as described above, the cooling power increased by the refrigerant subcooling can be utilized to reduce the amount of power through the capacity control of the compressor.

That is, the amount of power can be reduced by adjusting the rotational speed of the compressor by employing an inverter compressor having an inverter controller.

In the case of the present embodiment, too, as in Example 1, the power consumption of the refrigeration cabinet showcase having a large daytime load can be transferred to the late-night time, and the low-cost late-night electric power, which is about 40% of the general electric charge, can be used. The driving cost can be greatly reduced, and in particular, the present embodiment exhibits a higher driving efficiency due to a reduction in power than in the regenerative showcase system of the first embodiment.

On the other hand, even in the case of the refrigerated showcase system of the present embodiment, it can be composed of a multiple type (remote type) in which several showcases are connected together in one medium or large refrigerator, in this case also the same principle as described in the first embodiment The showcase is driven.

As described above, according to each embodiment of the present invention, not only to suppress the peak load during the summer day to contribute to the efficient use of energy and equalize the national power load, but also to reduce the energy saving and equipment cost by reducing the capacity of the refrigerator It is possible to provide a refrigerating cycle, a refrigerated showcase having the same, and a method of controlling the operation thereof, which can achieve the effect.

On the other hand, the present invention is not limited to the above embodiments, of course, various modifications, changes, and modifications are possible within the scope not departing from the technical spirit of the present invention.

That is, the rights of the present invention are not limited to the embodiments described above, but are defined by the claims, and those skilled in the art can make various modifications and adaptations within the scope of the claims. It is self evident.

For example, instead of employing an inverter compressor having an inverter controller, a power amount can be reduced by employing a compressor such as a multi-compressor unit in the system of the present invention.

According to the present invention, when the ice storage system is used for cooling the showcase, the peak load during the summertime is suppressed, thereby contributing to the efficient use of energy and leveling the national power load, and also reducing the capacity of the refrigeration equipment, thereby saving energy and reducing equipment costs. Industrial availability is very high because it can be obtained.

In other words, the present invention contributes to the reduction of summer peak power and power load leveling by the spread of ice heat storage system, and the reduction of power receiving facilities and peak power reduction by shifting the weekly load of the showcase to late night hours. It is an invention with very high availability.

In particular, the present invention can be applied to a variety of industrial cooling / refrigeration system as well as showcase, so that the field of application can be widened because the technology ripple effect is very large, the industrial applicability is very high.

1 is a reference diagram explaining the principle of cooling of the showcase

Figure 2 is a system configuration of the refrigeration showcase to which the refrigeration cycle apparatus using the ice storage heat of the present invention is applied

3a and 3b are for explaining the system operation of the cold storage showcase of the present invention,

Figure 3a is a system diagram showing the refrigerant flow in the late-night operating state

Figure 3b is a system configuration showing the refrigerant flow in the daytime operation state

Figure 4 is a graph showing a comparison of the operating state of the cold storage system of the present invention and the conventional non-cooling system

5 is a block diagram of a cold storage showcase system according to another embodiment of the present invention

Claims (10)

A refrigeration cycle comprising a compressor, a condenser, an expansion valve, and an evaporator on a refrigerant line; Refrigerant line for ice shaft and separately installed to connect the condenser and the compressor, An ice making heat exchanger installed on the ice storage refrigerant line; An expansion valve for ice making installed in front of an ice making heat exchanger of the ice storage refrigerant line; A supercooling refrigerant line installed separately to connect the condenser and the expansion valve; A subcooling heat exchanger installed on the subcooling refrigerant line; The ice-cold heat cycle using the ice storage heat characterized in that the ice heat exchanger and the sub-cooling heat exchanger is accommodated and provided with an ice storage tank filled with a heat medium. The method of claim 1, A connection point between the refrigerant line connecting the condenser and the evaporator and an ice making refrigerant line, a connection point between the refrigerant line connecting the condenser and the evaporator and an inlet line of the supercooling refrigerant line, and the condenser and the evaporator Three directions for controlling the flow direction of the refrigerant at the connection point between the refrigerant line connecting between the refrigerant line and the outlet line of the subcooling refrigerant line, and the connection line between the refrigerant line connecting the evaporator and the compressor and the ice making refrigerant line Refrigeration cycle apparatus using ice heat storage, characterized in that the valve is installed. In the operation of the refrigeration cycle apparatus of claim 1, When the heat medium contained in the ice storage tank is to be cooled, the operation control method of the refrigerating cycle apparatus using the ice storage heat, characterized in that to cool the heat medium in the ice storage tank by circulating a refrigerant to the ice making heat exchanger side accommodated in the ice storage heat tank. In the operation of the refrigeration cycle apparatus of claim 1, In the case of using the ice storage heat of the cooled heat medium, a part or all of the refrigerant passing through the condenser passes through the subcooling heat exchanger accommodated in the ice storage tank and then flows into the evaporator. A heat storage type showcase device comprising a refrigeration cycle apparatus using the ice storage heat of claim 1. The method of claim 5, The heat storage showcase device, The showcase is a plug-in type device in which one refrigerator is attached to a lower part of a unit showcase, or a heat storage showcase device characterized in that it is a remote type device in which several showcases are connected together in one medium or large refrigerator. . The method of claim 6, And the compressor is an inverter compressor having an inverter controller. In the operation control method of the heat storage showcase of claim 5, During the late night hours, the refrigerant passing through the compressor and the condenser circulates through the showcase, and when the showcase cooling is unnecessary, the refrigerant is circulated to the ice making heat exchanger housed in the ice storage tank to produce and store ice in the ice storage tank. Operation control method of the device. In the operation control method of the heat storage showcase of claim 5, The method of controlling the operation of the heat storage showcase device, characterized in that during the daytime part or all of the refrigerant passing through the condenser passes through the subcooling heat exchanger accommodated in the ice storage tank. In the operation control method of the heat storage showcase of claim 6, In the case of a remote type where several showcases are connected together in one medium or large refrigerator, During the late night hours, the refrigerant passing through the compressor and the condenser passes through several showcases. If the temperature of the specific showcase falls below the desired temperature, the refrigerant is circulated to the ice making heat exchanger housed in the ice storage tank to produce ice in the ice storage tank. and, The method of controlling the operation of the heat storage showcase device, characterized in that during the day time zone, the part or all of the refrigerant passing through the condenser is selectively introduced into each showcase after passing through the subcooling heat exchanger housed in the ice storage tank.

Images