KR101466864B1 - Multipurpose cooling system using phase-change material and control method thereof - Google Patents

Abstract

The present invention relates to a multifunctional cooling system using a phase change material (PCM). The multifunctional cooling system includes a central cooling tank, and a plurality of cooling devices. In the central cooling tank, a coolant is transferred to a central heat exchanger by an AC freezer and stored in PCM. The cooling devices receive the cold energy of the central cooling tank through brine. The central heat exchanger consists of duel pipes of an inner pipe and an external pipe to make the coolant and the brine transported in a single pipe, so that the heat exchange among the coolant, brine, and PCM is made concurrently.

Description

TECHNICAL FIELD [0001] The present invention relates to a multi-purpose cooling system using a phase change material and a control method thereof,

The present invention relates to a multi-purpose cooling system using a phase change material and a control method thereof. More particularly, the present invention relates to a phase-change material (hereinafter referred to as PCM) ), And the refrigeration, refrigeration, and cooling are distributed to and supplied to a plurality of cooling systems at the same time, thereby using the energy dispersion utilization efficiency to overcome the blackout of the overload time due to unbalanced power demand It is a technology that can be.

Generally, refrigerating / freezing / cooling devices apply the principle of a refrigeration cycle in which a phase change occurs while evaporating, compressing, condensing, or expanding a refrigerant, thereby cooling the inside by heat exchange.

Therefore, each product contains essential components such as a compressor for compressing refrigerant, a condenser for condensing, an expansion valve for expansion, and an evaporator for releasing heat to the atmosphere.

Showcases used for storage or display of refrigerated, frozen, and refrigerated foods in convenience stores, supermarkets, mart and department store food corners, butchers, restaurants, and grocery stores must maintain temperatures as low as -23 ° C to 8 ° C throughout the year Is an energy-consuming type of cooling and heating equipment with high operation cost. Refrigerators such as showcase, cryogenic refrigerator, air conditioner, Kimchi refrigerator, etc. are cooled by a refrigerator with a compressor, which produces low temperature refrigerant, and the produced low temperature refrigerant is heat exchanged in a heat exchanger installed inside the refrigerator.

As the number of places to store low-temperature foods such as convenience stores and supermarkets increases and global warming accelerates to increase the use of air conditioners for indoor air conditioning, it not only increases consumption of electric energy but also deepens summer peak load, Energy shortages such as blackouts are occurring every year due to shortage of electric power and shutdown of nuclear power plants.

As a result, research on energy saving using ice storage heat has been actively conducted in the showcase section, but it has not been activated so far and the power consumption during the day is not effectively reduced.

In addition, as described above, since the refrigeration cycle is applied to each of the cooling products, energy consumption is considerable, and when the refrigeration cycle of the cooling product installed in the room is operated, the operation noise of the compressor and the fan, And the efficiency of energy heat management and the like are deteriorating.

As a conventional technique, Patent Document 1 relates to a refrigeration showcase having a refrigeration system, which proposes a refrigeration showcase in which a PCM is cooled by a freezer and the brine is circulated and cooled by a heat exchange passage. However, The volume is small, the noise caused by the cooler, and the heat dissipation can not maintain a pleasant environment.

1. Korean Patent No. 10-1209482

The present invention has been made in view of the above needs, and it is an object of the present invention to provide a refrigerator, And provides a multipurpose cooling system that maintains a pleasant environment without noise and heat dissipation by distributing and supplying one PCM shaft cold / cool air to each dispersed equipment, and provides a high efficiency of energy utilization. Also, To provide an emergency means of maintaining the temperature.

According to an aspect of the present invention, there is provided a multi-purpose cooling system using a phase change material. The multi-purpose cooling system uses a phase change material to transfer a cooling force of a refrigerant cooled by an AC refrigerator to a phase-change material through a heat exchanger of a central- And the cold air of one central axial cooler installed in the main cooling unit is distributed and supplied to a plurality of cooling units in the room requiring different temperatures through the brine.

In an exemplary embodiment of the present invention, the heat exchanger of the central axial cold storage tank is composed of a double pipe composed of an inner pipe and an outer pipe so that the refrigerant and brine are transferred from one pipe, and heat exchange is simultaneously performed between the refrigerant, do.

In an embodiment of the present invention, the outer pipe of the double pipe is circulated by a circulation pump, the inner pipe of the double pipe is cooled by the AC refrigerator, the refrigerant cools the brine and the PCM simultaneously, The circulation pump supplies brine independently to each of the cooling devices, or supplies a brine distribution flow rate in cooperation with a two-chamber or three-chamber valve, and the valves are electronically controlled and controlled.

In one embodiment of the present invention, the central axis cold storage unit is integrally formed with the AC refrigerator to minimize the installation area and prevent the heat loss, and a plurality of AC refrigerators may be used to rapidly cool the PCM, And an auxiliary battery for operating the AC refrigerator.

According to an embodiment of the present invention, the cooling device is characterized in that a plurality of PCM packs are installed on an inner wall surface, and the cooling device includes a controller for controlling the temperature, the circulation flow rate of the brine, or the speed of the fan motor, And a secondary battery.

As another embodiment of the present invention, there is provided a refrigerator comprising: a central axial chiller for chilling the PCM through a refrigerant cooled by an AC chiller; and a plurality of chillers for supplying chilled air of the central axial chiller through a brine, The connection of the power source, the rotational speed of the fan, or the circulating flow rate of the brine are individually controlled by the PLC so as to maintain the optimum temperature according to the state or use state.

In the multipurpose cooling system using the phase change material, the cooling brine is chilled in one central cooling bath to distribute and supply the cooled brine using a pump, thereby achieving leveling of power demand by eliminating unbalance in power demand And the refrigerator of the individual refrigeration / cooling / cooling device can be removed to reduce power consumption and noise, and the device can be simplified to miniaturize or maximize the internal storage area.

In addition, the connection of the power source, the rotational speed of the fan, or the circulating flow rate of the brine can be individually controlled by the PLC, thereby maintaining the different prescribed temperatures for each cooling device.

Further, since there is no operation noise of a compressor, a condenser, an expansion valve, etc. installed in a conventional cooling device and a heat radiation loss caused by a heat exchanger, a pleasant indoor environment can be maintained and energy efficiency can be improved.

In addition, PCM packs can be installed in the room to keep the temperature for a long time, thereby suppressing or delaying the occurrence of deterioration or corruption during storage of refrigerated / frozen food. In case of power failure, It is possible to suppress the temperature rise in the semiconductor device.

1 is a schematic view of a multi-purpose cooling system using a phase change material according to the present invention.
2 is a cross-sectional view of a central heat exchanger of a multipurpose cooling system using a phase change material in accordance with the present invention.
3 is a schematic view showing a plurality of cooling apparatuses of a multipurpose cooling system using a phase change material according to the present invention.
4 is a cross-sectional view of a PCM pack of a cooling device of a multipurpose cooling system using a phase change material in accordance with the present invention.
FIG. 5 is a schematic view showing a configuration of a plurality of multi-purpose cooling systems using a phase change material according to the present invention. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings illustrate only the essential features of the invention in order to facilitate clarity of the invention and are not to be construed in a limiting sense since they are not shown in the accompanying drawings.

The multipurpose cooling system of the present invention can be classified into a refrigeration / freezing / cooling device according to the purpose and temperature of use, but is expressed as a 'cooling device' in a typical expression.

FIG. 1 is a schematic view of a multi-purpose cooling system using a phase change material according to the present invention. The multi-purpose cooling system using a phase change material includes a central axis cooling apparatus 100, a plurality of cooling apparatuses 200, Pump and a transfer pipe (300).

The central axis refrigerator 100 takes the heat of the PCM stored in the axial chiller through the central heat exchanger 120 to change the phase of the refrigerant cooled by the AC refrigerator 110, It is possible to minimize the peak power amount in the overload time zone by minimizing the weekly power consumption by operating the AC refrigerator 110 by night power and by using the cold air required in the daytime time zone by cooling the PCM in the central axis cooler. The central axis cooler 100 is installed separately outdoors and can be cooled in PCM as required in a suitable time period during the day,

PCM utilizes the property of absorbing or releasing heat when a material undergoes a phase change, and it is advantageous that the heat quantity per unit mass is large. Water (latent heat: 67 to 80 kcal) or a hydrate of an organic or inorganic salt can be used as an example of the PCM, and a substance having a larger latent heat than water is preferable. In the present invention, it is preferable to use a eutectic salt PCM (sub zero eutectic PCM) melting at 0 캜 or less to have a temperature range of -2 캜 to -62 캜 and to blend a nucleating agent and a corrosion inhibitor or microorganism- But the present invention is not limited thereto, and a pack or capsule type may be used.

Brine is a cooling power transmission antifreeze with a low freezing point. It can use a low temperature fluid such as calcium chloride, brine or sodium chloride. It can also be used as a cryoprotectant such as ethylene glycol (EG) or propylene glycol (PG) .

The cooling device 200 for cooling, cooling, or freezing installed in the room receives the cool air of the central axial cooler 100 from the brine without having its own freezer. That is, the cooled brine is supplied to the heat exchanger 210 of the cooling device by the transfer pipe 300, and the internal temperature is kept constant by using the forced convection. The cooling device 200 may be one of a refrigerator, a refrigerator, a cooling device such as an air conditioner, a refrigerator, and a refrigerated showcase, or a plurality of devices having the same purpose. The cooling device 20 according to the present invention does not require a compressor, a condenser, an expansion valve, or the like, so that it is possible to maintain a pleasant environment without operating noise generated by a conventional cooling device and heat loss due to a heat exchanger, . The transfer pipe 300 includes two pipes as a supply pipe for supplying the cooled brine and a return pipe for returning the cooling power to the brine.

The central heat exchanger 120 is composed of a double pipe composed of an inner pipe 121 and an outer pipe 122 so that the refrigerant and brine are transferred from one pipe, and heat exchange is simultaneously performed between the refrigerant, the brine, and the PCM. Since the heat exchange between the refrigerant and the brine and the PCM is performed at the same time, the condensation time is faster and the heat exchanging area is wider than that of the single pipe, so that a large amount of PCM can be cooled. Simultaneous heat exchange between the refrigerant and the brine and the PCM can reduce the power consumption due to shortening of the cooling time, and the circulation of the refrigerant and the brine can be performed in one pipe to minimize the volume of the heat exchanger, Installation is possible. In addition, one or more circulation pumps can be used to shorten the cold transfer time.

FIG. 2 is a cross-sectional view of a central heat exchanger of a multi-purpose cooling system using a phase change material according to the present invention, in which two pipes 121 and 122 are connected to a PCM of a central axial cooler 100, A portion of the inner tube 121 and the outer tube 122 are brought into contact with each other.

Also, the refrigerant is circulated through the inner pipe 121 of the double pipe, and the brine is delivered to the outer pipe 122 by the circulation pump, so that the refrigerant can simultaneously cool the brine and the PCM. A certain portion of the inner tube 121 and the outer tube 122 are periodically abutted against each other so that the PCM and the brine can directly exchange heat via the refrigerant circulated in the inner tube 121. Thus, rapid heat exchange is performed to reduce power consumption . As shown in FIG. 2, the dual tubes 121 and 122 may be of a spiral tube type or a coaxial tube type.

FIG. 3 shows an embodiment of a multi-purpose cooling system using a phase change material according to the present invention. The cooling system 100 includes a central air-cooling unit 100 installed outside the room, an air conditioner serving as an indoor cooling unit, a showcase, This is an example of distributing the brine to a common refrigerator. The central axis refrigerator 100 may be one PCM for multipurpose use such as refrigeration, freezing, and cooling of the cooling device 200. [ The capacity of the AC refrigerator 110 of the central axial cooling unit 100 and the amount of PCM filled in the central axial cooling unit 100 are designed to be optimal combinations according to the number of cooling units 200 to be used, can do. In addition, the brine flowing between the heat exchanger 210 of the cooling device 200 and the central axial cold storage 100 may be formed by using materials of different temperature ranges or by using one material for the heat exchange The temperature can be selected in such a manner that the desired temperature is adjusted by mixing the air of the outside air using the temperature region material of the temperature region.

In addition, the central axial cold storage 100 may be manufactured integrally with the AC refrigerator 110 so as to minimize the installation area and reduce heat loss.

In addition, the central axial chiller 100 includes one or more AC chillers 110 to rapidly chill the PCM. One or more of the AC refrigerator 110 may be provided with a circular tube and a flat tube having a plurality of cells instead of a pin type and a pin type in order to shorten the cooling time and reduce the volume of the entire central axis cold storage.

Also, the central axis refrigerator 100 includes an auxiliary battery 130 that operates the AC refrigerator 110 at the time of power failure or operates only the electric components except the AC refrigerator. A DC auxiliary battery 130 may be included to operate the AC refrigerator 110 during a power failure, and a converter or the like may further be included for conversion into AC power. The auxiliary battery 130 can be recharged while the AC power is normally supplied.

In addition, when the temperature of the PCM of the central axis cooler 100 falls below the set temperature, the operation of the circulation pump for automatically detecting the temperature of the PCM and circulating the power of the AC refrigerator 110 and the brine is stopped to minimize the power consumption It can be configured to operate the circulation pump and fan when the room temperature of the freezing and refrigerating products rises.

Optionally, the circulation pump 220 may be associated with a two- or three-port valve, which may be of an electronic type capable of regulating the brine circulation flow rate. Further, one end of the conveyance pipe 300 is connected to the circulation pump 220, and it is possible to control opening / closing suitably when the cold air is conveyed using the three-way valve and when the brine circulation is performed inside the apparatus heat exchanger 210 have. The apparatus heat exchanger 210 may adopt a circular copper tube and an aluminum tube and a pin type including a pin type or an elliptical type including a plurality of cells for optimum performance.

4 is a cross-sectional view of a PCM pack 240 additionally installed in the cooling device 200. The PCM pack 240 includes a plurality of PCM packs 240 arranged in the chamber inner walls of the cooling device 200, The efficiency can be increased. By providing the PCM pack on the inner wall of the chamber of the cooling device 200, it is possible to secure the heat insulating performance without decreasing the volume of the room and to extend the temperature holding time. The wall surface on which the PCM pack 240 is installed is provided with a heat insulating material to prevent cold air flowing out to the outside, and can be opened to the inside. The PCM pack 240 opened to the inside can easily exchange heat with the inside of the room, thereby keeping the temperature of the room constant. The PCM pack 240 can be made of a nylon article or a polyethylene (P.E.) material having a PCM of a temperature range suitable for the characteristics of each cooling apparatus 200 and resistant to thermal deformation. And a PCM mounting basket to which the PCM pack 240 can be easily fixed to the cooling device 200. The basket may have a plurality of air contact holes And includes a mounting hole for facilitating fixing in the cooling device 200. [ In addition, the PCM pack 240 can facilitate the flow of cooled air, including the airflow passages 241, by storing the PCMs separately. The installation of the PCM pack 240 provides an effect of increasing the temperature holding time and increasing the storage weight as well as the effect of heat insulation.

The cooling device 200 further includes a temperature sensor 250, a fan speed controller, a central controller, an air curtain module, or an auxiliary battery.

The temperature sensor 250 may sense the room temperature. A central axis cooler 100 and a temperature sensor 250 for sensing the internal temperature of each of the cooling devices 200 are required for automatic temperature control. The temperature sensor 250 of the central axial chiller 100 may be of the submerged type for immersion in the PCM storage and the temperature sensor 250 of the cooling device 200 may be an air- Can be adopted.

The central controller can set the temperature, the brine circulation flow rate, or the rotation speed of the fan motor. The rotational speed of the fan 230 and the circulation flow rate of the brine can be automatically or manually controlled according to the internal set temperature.

The air curtain module is installed at the inner upper side of the door, and can prevent outside air from flowing into the room when the door is opened and closed. In a showcase, a kimchi refrigerator, and a general refrigerator, outside air flows in and out of a foodstuff, and in the case of an air conditioner, opening and closing is frequent due to entrance and exit of a person, . When the air curtain module is installed at the upper part of the door to reduce the influence of the external air inflow, the air curtain automatically operates when the door is opened, so that the indoor (indoor) temperature can be kept constant.

The auxiliary battery can be operated at the time of power failure to operate the fan 230 or the circulation pump 220. [ A DC auxiliary battery 290 that can be used when the AC power is cut off, and may further include a converter and the like for conversion to AC power. When the voltage of the auxiliary battery 290 drops, the auxiliary battery 290 can be recharged by the AC power supply at normal times.

The connection of the power source, the wind speed of the fan or the circulation flow rate of the brine can be individually controlled by a PLC (programmable logic controller) so as to maintain the optimum temperature according to the power state or use purpose of the cooling device 200. The internal temperature can be maintained constantly to keep the state of the stored product reliably. However, since the opening and closing of the door and the power supply state can be greatly affected, the automatic control can maintain the optimum temperature and save energy.

The control method of the multi-purpose cooling system according to the present invention includes the steps of operating the AC refrigerator 110 when the PCM in the central axis refrigerator 100 rises above a certain temperature, when the PCM in the central axis refrigerator 100 has cooled sufficiently Stopping the AC refrigerator 110, including an auxiliary battery 130 in addition to an AC power source in the central axis refrigerator 100, and a circulation pump of the central axis refrigerator 100 in an off- , Operating the fan (230) and the circulation pump (220) to rapidly cool the temperature at the time of opening and closing the door, assisting the cooling device (200) And operating the fan (230) and the circulation pump (220) in the cooling device using the auxiliary battery (250) when the fan (230) is powered off. To automatically or manually control power consumption The efficiency can be improved and the proper internal temperature can be maintained.

FIG. 5 is a view showing another example of a cooling system for distributing a brine to a plurality of showcases having different prescribed temperatures as an air conditioner and a food storage device, which are indoor air cooling devices, It is an example.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

100: Central axis cooler 110: AC refrigerator
120: central heat exchanger 121: inner tube
122: outer tube 130: auxiliary battery
200: Cooling unit 210: Device heat exchanger
220: circulation pump 230: fan
240: PCM Pack 250: Temperature sensor
300: transfer pipe

Claims (9)

A cooling system for transferring a cooling force of a refrigerant cooled by an AC refrigerator to a phase-change material (PCM) through a heat exchanger of a central-axis refrigerator,
The cold air of one of the central cooling shafts installed outdoors is distributed and supplied to a plurality of cooling apparatuses having different cooling temperature levels through the flow distribution of the brine,
The AC refrigerator is an integral type that directly cools the PCM and the brine of the central axis cooler to minimize the installation area and prevent the heat loss,
The heat exchanger of the central axis cold storage tank is installed in the PCM storage tank as a double pipe through which refrigerant and brine are transferred from one pipe,
The double tube is composed of a spiral tube type or a coaxial tube type in which a certain portion of the inner tube and the outer tube periodically abuts,
Wherein the outer tube is circulated by a circulation pump and the inner tube is cooled by the AC refrigerator to cool the brine and the PCM to heat exchange. delete delete The method according to claim 1,
Wherein the circulation pump supplies brine independently to each cooling device, or in conjunction with a two- or three-way valve to supply a brine distribution flow rate, the valves being electronically controlled and adjusted. The method according to claim 1,
A plurality of AC refrigerators to rapidly cool the PCM, or an auxiliary battery to operate an electrically operated component except for the AC refrigerator at a power failure. The method according to claim 1,
Wherein the cooling device further comprises a plurality of PCM packs installed on an inner wall surface thereof. The cooling device according to claim 1,
Controllers that individually control the temperature, the brine circulation flow rate, or the speed of the fan motor and
Further comprising an auxiliary battery for power failure. A control method for a multipurpose cooling system comprising a central axis cooling unit for cooling the PCM through a coolant cooled by an AC refrigerator and a plurality of cooling units for cooling the cooling air of the central axis cooling unit by a flow rate distribution of the brine, In this case,
The heat exchanger of the central axis cold storage tank is installed in the PCM storage tank as a double pipe through which refrigerant and brine are transferred from one pipe,
The double tube is composed of a spiral tube type or a coaxial tube type in which a certain portion of the inner tube and the outer tube periodically abuts,
The outer tube is circulated through the circulation pump by a circulation pump, and the inner tube is an integral type in which the refrigerant is transferred by the AC refrigerator, and the refrigerant cools the brine and the PCM to heat-
The control of the connection of the power source, the rotational speed of the fan, or the circulating flow rate of the brine is individually controlled by a PLC (programmable logic controller) so as to maintain the set temperature according to the power state or use state of the cooling device,
Operating the AC refrigerator when the PCM in the central axial chiller rises above a predetermined temperature;
Stopping the operation of the AC refrigerator when the PCM in the central axial chiller is sufficiently cooled;
A step of operating the circulation pump of the central axis cooler by using the auxiliary battery when the power is off and recharging the auxiliary battery when the AC power is normally supplied;
Operating the fan and the circulation pump in the cooling device using the auxiliary battery in the cooling device and using the auxiliary battery in the power saving mode;
Wherein the cooling device includes a temperature controller and automatically or manually controlling the speed of the fan motor according to a set temperature inside the cooling device. delete

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