JP4873293B2 - Package air conditioner performance degradation prevention system using solar cells - Google Patents

Description

  The present invention relates to a multi-package air conditioner (also referred to as a multi air conditioner), an outdoor unit including a compressor and a heat exchanger for exhaust heat functioning as a condenser during cooling, an indoor unit including a heat utilization side heat exchanger, and a decompression unit. More particularly, the present invention relates to a cooling system using a packaged air conditioner that supercools refrigerant between an outdoor unit and an indoor unit.

  The introduction of packaged air conditioners such as multi air conditioners is progressing with air conditioning equipment, but the efficiency of exhaust heat from the outdoor unit to the outside air is reduced during heavy loads. At the time of cooling, the refrigerant temperature and pressure on the discharge side of the compressor rise and the efficiency decreases, and in the worst case, the device may stop. This is generally called a high pressure cut. As a measure to prevent efficiency reduction during high-cooling cooling loads such as high-pressure cuts such as high-pressure cut, it is used as a heat exchanger for exhaust heat of outdoor units (acts as a condenser during cooling. Hereinafter referred to as "condenser". ) By spraying water and cooling the refrigerant with the latent heat of evaporation of the water (Patent Document 1), or using external cold heat, for example, heat transfer water in a heat storage tank or cold water return water that has been heat exchanged with an air conditioning load. A refrigerant supercooling system (Patent Document 2 and Patent Document 3) that cools the refrigerant through a supercooler in the previous stage has been developed.

On the other hand, systems using solar cells are often unstable due to the use of sunlight, and are often used for building facilities by grid connection or storage in a storage battery. In either case, an AC / DC converter and an adjusting device such as an inverter or converter for adjusting the output must be installed, which complicates the system and increases costs. Therefore, it is desirable that the current generated by the solar cell can be directly used as a direct current, but there are not many devices that use a DC power source such as electric lamps and blowers, and the devices are generally required to have stable power. It is difficult to use.
Then, the processing method which reduces an installation cost using the Peltier device which directly heat-exchanges with the direct current produced in the solar cell as an air conditioner is also disclosed (patent document 4).

JP 2003-166744 A JP 2004-211998 A JP 2005-249221 A Japanese Patent Laid-Open No. 08-178340

  However, in the treatment method disclosed in Patent Document 1, it is necessary to pay attention to the anticorrosion measures for the condenser which is against water saving and is subject to water quality management and water spraying. In this respect, in the methods shown in Patent Document 2 and Patent Document 3, the above problem is improved because the supercooler for supercooling the refrigerant is constituted by a closed system and the interior of the container is constantly passed. There was room for improvement in the construction work, such as the installation of a heat transfer pipe for supercooling and connection with a supercooler.

  The idea of using the Peltier element itself as it is for air conditioning as described in Patent Document 4 is that the degree of load that can be covered is significantly smaller than the load when using the current packaged air conditioner, and the same In order to obtain a cooling effect, the initial equipment cost and the power bill are not realistic because they lack economic efficiency.

  Accordingly, an object of the present invention is to provide a cooling system that can stably perform cooling even at high loads such as in midsummer, and has low operating costs for stable cooling operation and improved maintenance and workability. Is to provide.

In order to solve the above problems, the invention of claim 1 is directed to an outdoor unit including a compressor and a heat exchanger for exhaust heat functioning as a condenser during cooling, an indoor unit including a heat utilization side heat exchanger, and a pressure reducing device. In a cooling system using a packaged air conditioner comprising: a Peltier element that further includes a solar cell and supercools the refrigerant in the refrigerant outlet pipe downstream of the compressor outlet or the condenser and between the expansion valve near the indoor unit The Peltier element is disposed outside so as to cover at least a part of the pipe line, and the Peltier element has a heat-absorbing surface as a pipe outer wall side of the refrigerant outlet pipe, and a heat-radiating surface as an outer wall surface of the cylindrical cover. A package air conditioner performance deterioration prevention system using a solar cell, wherein the system is cooled, and a DC power source is supplied from the solar cell to the Peltier element .
The heat utilization side heat exchanger cools the heat utilization destination by a direct expansion method, and the object to be cooled is a gas such as air. The heat exchanger for exhaust heat is, for example, a water-cooled or air-cooled condenser, and the refrigerant is further cooled by a packaged air conditioner system provided with the condenser when the outdoor heat load such as midsummer is large. Here, since the solar cell is adopted as the refrigerant cooling means to be added, the degree of solar radiation and the outdoor temperature can be regarded as a substantially proportional relationship, so that a higher efficiency system can be constructed with a higher load. In addition, when the refrigerant gasified by heat exchange in the indoor unit during cooling or other heat load is liquefied and led to the compressor, the DC current supplied from the solar cell is simply configured without taking a complicated configuration. The system can cool the refrigerant. The Peltier element may be wound around the pipeline, or may be unitized and indirectly (cold) heat applied to the pipeline as described below.

Further, in the invention of claim 2, in addition to the above configuration, the solar cell is installed in an orientation corresponding to a time zone with a large cooling load of the building, and the Peltier element is configured to be short along the pipeline as a cooling unit . The cylinder cover is connected to continuously cover the pipeline, and the fins are intermittently attached by being sandwiched between the cylinder covers from the outer wall of the cooling unit toward the outside. Features.
“Refrigerating and Air Conditioning Technology” published by the Japan Society of Refrigerating and Air Conditioning Engineers (April 1, 2001, 2nd revised edition, 185 pages edited and published by Japan Society of Refrigerating and Air Conditioning Engineers) It is shown that it reaches the peak of heat load (all are 4000 W or more) between 14:00, 16: 00-17: 00 in the west direction, and 8: 00-9am in the east direction. If the solar cell according to the present invention is provided in an orientation corresponding to a time zone with a large load, the amount of (cold) heat received from the solar cell can be increased. In addition, by providing the cooling unit in front of the heat exchanger for exhaust heat, the operation load is reduced without requiring modification of the outdoor unit.

Furthermore, in the invention of claim 3, in addition to the configuration of claim 2, the cooling unit has a rectangular outer shape, and a latent heat storage capsule or a phase change is possible between the cooling unit and the pipe line in the cooling unit. The working fluid is filled.
The rectangular outer shape makes it easy to place on a flat surface.If the working fluid is filled in the gap between the rectangular inner wall surface and the circular outer wall surface of the pipe, the heat transfer surface of the Peltier element and the outer wall surface of the refrigerant tube Energy transfer is actively performed between them, and a cooling system with improved heat exchange efficiency with respect to the installation area can be constructed.

In carrying out the above invention, the lower end of the solar cell may be installed at a position higher than the lower end of the heat exchanger for exhaust heat of the outdoor unit, and may be provided so as to shield the outdoor unit from solar radiation.
With this configuration, the solar cell not only provides auxiliary heat to the cooling system, but also has an eaves function for the outdoor unit, and prevents a decrease in efficiency due to solar radiation derived from radiant heat, heat accumulation in the unit, and the like.

The invention of claim 4 is provided with a coolant water cooling means in addition to the structure of any of claims 1 to 3 , wherein the solar cell and the Peltier element are integrated, and the heat dissipation surface and the back surface of the solar cell are provided. By supplying cooling water in between, water cooling can take more heat than air cooling, so the heat absorption efficiency of Peltier elements and the power generation efficiency of solar cells ("Solar Power Generation Introduction Guidebook", page 92) The refrigerant is cooled in a state where the Energy / Industrial Technology Development Organization is up.
In the present invention, it is possible to integrate the solar cell and the Peltier element, which are the main members, and collect the piping and electrical / communication wiring around the integrated unit.

According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect , the water cooling means is a cooling tower, a unit in which the solar cell and the cooling unit are integrated is a solar cell, and a back surface of the solar cell. The cooling unit is integrated in relation to the cooling unit, and the cooling unit is configured such that water is introduced to the side receiving solar radiation across the Peltier element, and refrigerant is guided to the back side thereof, the water is a cooling tower, and the refrigerant is the pipe line. It is characterized by being configured to circulate between.
According to this configuration, the above-described effects can be obtained with a standardized configuration.

  The effect of the present invention is that the output of a solar cell increases following a high load, so that when viewed from the refrigeration cycle, the higher the load, the higher the efficiency of the cooling system, the unexpected equipment efficiency such as high-pressure cut That is, the system can be stably operated avoiding the decrease, the maintenance can be easily performed, the workability can be improved, and the operation cost for the high efficiency and stable operation described above is low.

  FIG. 1 shows a basic configuration of a cooling system 1 according to the present invention. In this example, the cooling system 1 is a cooling system that cools indoor air, and the cooling system 1 includes a solar cell 2 and a packaged air conditioner 2 including an indoor unit 3a and an outdoor unit 3b as main devices. The indoor unit 3a cools indoor air as a cooling heat load. The indoor unit includes an evaporator as a heat utilization side heat exchanger, an expansion valve as a decompression device, and a blower for circulating air through the evaporator. The outdoor unit 3b includes a compressor 3b1 and a condenser 3b2 as a heat exchanger for exhaust heat in addition to the compressor 3b1. The indoor unit 3a and the outdoor unit 3b are connected by a refrigerant pipe 5 including a refrigerant forward pipe 5a and a refrigerant return pipe 5b. A Peltier element 4 as a main member according to the present invention is provided in the refrigerant forward pipe downstream of the outlet of the compressor 3b1, in this example, downstream of the condenser 3b2 and the expansion valve near the indoor unit. In the drawing, there is one indoor unit. However, it is of course possible to connect a plurality of indoor units to the outdoor unit 3b through joints. In this case, the Peltier element is preferably provided closer to the condenser 3b2 than the joint.

In the Peltier element 4, a p-type semiconductor and an n-type semiconductor are alternately connected in series by electrode plates as disclosed in Patent Document 3, and insulating plates are disposed on the front and back of these semiconductors. Can be illustrated. Then, by connecting the electrode plate of the Peltier element 4 to the positive electrode and the negative electrode and causing a direct current to flow, one insulating plate absorbs heat and the other insulating plate generates heat. In this example, the heat absorption side of the electrode plate is wound around the refrigerant forward pipe 5a. But you may make it surround a refrigerant | coolant pipe | tube outer wall surface in contact with four electrode plates. The refrigerant pipe is covered with a heat insulating material except for a surface that contacts the Peltier element and receives cold heat. In terms of construction, it is preferable to insulate in advance so as to slightly overlap in the tube axis direction of the surface in contact with the Peltier element.
As the solar cell 1, a known type such as a silicon type or a dye-sensitized type can be adopted, and the shape is a panel type and a double-sided light receiving type can also be adopted. ing.
The solar cell 1 is connected to the Peltier element 4 via the electric wire 7 and supplies the current generated by sunlight obtained by the light receiving panel to the electrode plate of the Peltier element 4. The power generation capacity of the solar cell is determined in accordance with the maximum cooling capacity of the Peltier element, and determines the solar cell body area, installation orientation, and installation angle.

  Usually, the output of a solar cell is approximately proportional to the intensity of solar radiation incident on the surface of the solar cell. In general, the solar radiation intensity is greatest at south-central time when the solar altitude is highest. The maximum load of a packaged air conditioner varies depending on the use and direction of the building, but the peak load often comes between 12:00 and 15:00. Therefore, the light receiving surface of the solar cell panel is also arranged in the south direction so that the solar cell output is maximized in advance when the maximum load of the building multi is reached. The refrigerant in the cooling system of this example is converted into high-pressure gas by the compressor 3b1, liquefied by the condenser 3b2, and is supercooled to a position where the liquid refrigerant is covered by the Peltier element 4 of the refrigerant forward pipe 5a. The supercooled liquid refrigerant is vaporized at a high COP in the evaporator of the indoor unit 3a by the expansion valve. Alternatively, due to the presence of the Peltier element functioning as a supercooler, the heat radiation amount of the condenser 3b2 can be reduced, and the above-described problem of high-pressure cut can also be avoided.

Since the direct current generated by the solar cell can be directly supplied to the Peltier element, a simple circuit configuration that does not require an inverter or other device that converts AC to DC can be achieved. The direct current generated in this way can be supplied at a high output by the Peltier element. Also, converters for adjusting solar cell output, etc., because the output characteristics of solar cells that change depending on solar radiation intensity and the cooling load characteristics of packaged air conditioners that generally increase when the weather is good and decrease when the weather is bad match It can be eliminated.
According to the above configuration, renewal that improves the cooling capacity of the existing equipment is easy. In other words, the indoor unit and the outdoor unit are not modified at all, and a new solar cell is installed and the work is only performed around the refrigerant pipe (the heat insulating material covered with the refrigerant pipe needs to be peeled off at the Peltier element mounting site). Therefore, it is possible to easily cope with an increase in internal load caused by OA equipment.

FIG. 2 shows another embodiment. Here, an example is shown in which the Peltier element used in the embodiment of FIG. 1 is configured as a cooling unit (the system configuration is not changed). That is, a rectangular cylindrical cover 14a is constituted by four plate-like Peltier elements 4 surrounding the outer wall of the refrigerant outgoing pipe 5a. The cylindrical cover 14a may be a long (eg, 3 m) integral, but in the example of FIG. 2, 16 short (eg, 20 cm) cylindrical cover 14a are sandwiched with fins 14b serving as heat sinks therebetween. Connected and formed. As the fins, those having good corrosion resistance and thermal conductivity such as aluminum, galvanized steel, and stainless steel are preferable. The fins are attached to the heat radiation surface (outer wall surface of the cylinder cover) of the Peltier element that forms the cylinder cover 14a, I'm missing. Furthermore, a cylindrical body that is integrally formed with the fin using the same material as the fin described above may be overlapped on the outside of the Peltier element. In any case, the cooling capacity of the Peltier element is adjusted by the mounting length so that the temperature of the liquid refrigerant is between 10 and 40 ° C.
The opening in the tube axis direction of the cylinder cover 14a is closed with a cap so as not to reduce the heat absorption efficiency. For this construction, for example, a soft and adhesive cap is preferable so that no gap is generated between the refrigerant forward pipe 5a and the cylindrical cover 14a. Thus, the cylinder cover 14a is formed airtight. Here, the endothermic surface of the Peltier element may be in contact with the outer wall of the refrigerant refrigerant forward pipe 5a, but may be spaced. In the latter case, a sealed air layer serves as a cold heat transfer medium.
In the above configuration, the Peltier element supplied with electric power from the solar cell also serves as a cover for the refrigerant pipe. Usually, when building refrigerant piping for buildings is piped outdoors, a plastic or steel plate cover is used to protect the piping portion from wind and rain and to improve its appearance. By using a method of enclosing with a Peltier element (built-in) cover, the above object is satisfied, and the Peltier element can be easily attached.

  In the embodiment shown in FIG. 3, a filler 14c is accommodated between the cylinder cover 14a and the refrigerant forward pipe 5a. As the filler, working fluids used in heat pipes such as ammonia and perfluorocarbon as well as latent heat storage capsules can be adopted. With this configuration, the heat is easily transferred between the outer surface of the tube and the Peltier element.

  In the embodiment shown in FIG. 4, the solar cell panel is provided to be inclined so as to receive the entire surface of the solar cell through an appropriate support frame so as to cover the outdoor unit. It is preferable that the lower end of the solar cell panel is located above the lower end of the outdoor unit, but the lower end of the solar cell panel is higher than the upper end of the condenser of the outdoor unit as in this example, and in the direction of solar radiation from the outdoor unit. It is more preferable that the projectors are installed at an interval and inclined. Since both solar cells and outdoor units are often installed on the rooftop, the solar cell itself plays the role of sun protection by installing the solar cell on the top of the outdoor unit in this way, so the capacity of the outdoor unit due to direct sunlight Decline can be prevented.

Although the above embodiment cooled the Peltier device 4 with air, this invention is a water cooling system which cools the Peltier device 4 with water. An example is shown in the embodiment of FIG. In this example, a solar cell 2 and a Peltier element 4 constitute a cooling unit 24 that is integrated in a configuration that will be described later. The configuration of the indoor unit 3a is the same as that of the above-described embodiment. Similarly, the refrigerant pipe 5 including the refrigerant forward pipe 5a and the refrigerant return pipe 5b is connected to the indoor unit 3a. In this example, the refrigerant forward pipe 5a is a cooling unit in which the solar cell 2 and the Peltier element 4 are integrated. The cooling unit 24 is connected to the cooling tower 8 via a cooling water pipe, and the cooling water is guided into the unit. If a heat exchanger is provided between the cooling unit and the cooling tower 8, the inside of the cooling system can be constructed in a closed system, and contamination in the system can be prevented.
In FIG. 5, an outdoor unit 3b including a compressor 3b1 and a condenser 3b2 is illustrated, and the refrigerant circulates in the order of the indoor unit 3a → the cooling unit 24 → the outdoor unit 3b. This is an example in which the existing cooling tower is used to enhance the effect when refurbishing from the central heat source method used to the individual air conditioning method using a packaged air conditioner. In this sense, the cooling tower 8 uses existing gas-liquid contact means such as an air washer, another system of chilled water return pipe (for example, water after cooling the production apparatus in the case of a factory) and water for fire extinguishing. In the case of the method using water, miscellaneous water such as hand-washing water, reused water, and in some cases, sewage such as toilet drainage can be used.

FIG. 6 shows details of the cooling unit. A Peltier element to which electric power is supplied from a solar cell and a cooling water pipe for heat dissipation are unitized. Specifically, the solar cell panel 24a is formed as a unit surface portion at the closest position from the sunlight irradiation side, and the rear surface of the cooling water flow path 24b, the Peltier element 24c, and the refrigerant flow path 24d are canned. Is provided inside. One surface of the casing is a surface of the panel 24a. The cooling water flow path 24b and the refrigerant flow path 24d are connected by piping so that the flow directions are orthogonal to each other with the Peltier element 24c interposed therebetween. Further, the cooling water flow path 24b and the refrigerant flow path 24d may be hollow chambers, and can be configured so that each forward pipe (liquid refrigerant pipe in the case of a refrigerant) is led out from the outlet of each flow path after heat exchange. However, here, a coil (heat exchanger) is housed in each flow path portion, and the above-described working fluid is used. A flow rate adjusting valve is interposed in the cooling water passage 24b, and a check valve is interposed in the refrigerant passage 24d. The Peltier element 24c is disposed so that the heat radiation surface faces the cooling water flow path 24b and the heat absorption surface faces the refrigerant flow path 24d.
The direct current generated by the solar cell is supplied to the Peltier element and used for cooling the refrigerant piping. The cooling pipe removes the heat taken by the Peltier element from the refrigerant piping and the heat generated by the solar cell power generation, and the cooled heat is dissipated by the cooling tower. Adoption of a water cooling method using cooling water contributes to an improvement in solar cell efficiency and heat dissipation of the Peltier element compared to air cooling.
The schematic energy flow of the water cooling system is as shown in FIG. In addition, the installation of a cooling unit can illustrate the aspect which installs the cooling unit 24 in the position of the solar cell 2 of description of FIG.

  INDUSTRIAL APPLICABILITY The present invention can be applied to an application for preventing a decrease in cooling capacity in an air conditioning system and other cooling systems.

It is a basic apparatus block diagram of the cooling system to which this invention is applied. It is a perspective view of the cooling unit which concerns on embodiment of this invention. It is sectional drawing of the cooling unit which concerns on embodiment of this invention. It is a figure which shows the Example of the cooling system to which this invention is applied. It is a basic device block diagram at the time of cooling the Peltier device of the present invention by a water cooling system. It is detail drawing of the cooling unit which concerns on FIG. It is a figure which shows the general energy flow of the water cooling system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling system 2 Solar cell 3 Package air conditioner 3a Indoor unit 3b Outdoor unit 3b1 Compressor 3b2 Condenser 4 Cooling unit 8 Cooling towers 14 and 24 Cooling unit

Claims (5)

In a cooling system using a packaged air conditioner composed of an outdoor unit equipped with a compressor and a heat exchanger for exhaust heat functioning as a condenser during cooling, an indoor unit equipped with a heat utilization side heat exchanger, and a decompression device, further solar cells A Peltier element that supercools the refrigerant is provided outside the refrigerant outlet pipe between the outlet of the compressor or downstream of the condenser and the expansion valve near the indoor unit , and covers at least a part of the pipe. The Peltier element is configured such that the heat absorption surface is on the pipe outer wall side of the refrigerant forward pipe, the heat dissipation surface is cooled with water as the outer wall surface of the cylindrical body cover, and the solar cell is connected to the Peltier element. A package air conditioner performance deterioration prevention system using solar cells, characterized in that a direct current power supply is supplied from a solar cell. The solar cell is installed in a direction corresponding to a time zone when the cooling load of the building is large , and the Peltier element is connected to the cylindrical body cover which is configured to be short along the pipeline as a cooling unit, and the pipeline is continuous. The solar cell according to claim 1, wherein the solar cell according to claim 1, wherein the solar cell is intermittently attached by being covered and fins are sandwiched between cylindrical covers outward from the outer wall of the cooling unit. The package air conditioner performance deterioration prevention system used. The cooling unit has a rectangular outer shape, and a latent heat storage capsule or a phase-changeable working fluid is filled between the cooling unit and the pipe in the cooling unit. Package air conditioner performance deterioration prevention system using the solar cell described. It is integrated from the previous SL solar cell and the Peltier element, by supplying the cooling water between the radiating surface and a rear surface of a solar cell of the integrated Peltier element, the power generation efficiency of the endothermic efficiency and solar cell of the Peltier element The package air conditioner performance deterioration prevention system using a solar cell according to claim 1, 2, or 3 , wherein the refrigerant is cooled. The water cooling means is a cooling tower, a unit in which the solar cell and the cooling unit are integrated is a solar cell on the surface that receives solar radiation, and the back surface thereof is integrated in relation to the cooling unit, and the cooling unit is Water is introduced to the side that receives solar radiation across the Peltier element, and a refrigerant is guided to the back side of the Peltier element, and the water is configured to circulate between the cooling tower and the refrigerant. The package air-conditioner performance fall prevention system using the solar cell of Claim 4 .

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