CN114710932A

CN114710932A - Refrigeration/heat pipe composite type cabinet air conditioning system and control method thereof

Info

Publication number: CN114710932A
Application number: CN202210322091.5A
Authority: CN
Inventors: 李骏; 郭世良; 都文星; 张伟; 曾凯
Original assignee: Suzhou Blackshields Environment Co ltd
Current assignee: Suzhou Blackshields Environment Co ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2022-07-05

Abstract

The invention relates to the technical field of cabinet temperature control equipment in the communication, power and industrial control industries, in particular to a refrigeration/heat pipe composite cabinet air conditioning system and a control method thereof. According to the invention, through the automatic control system, the automatic operation of the heat pipe system and the vapor compression refrigeration system is realized according to different working conditions, so that the system always operates in an energy-saving mode under different working conditions, the temperature in the cabinet is ensured to be in a reasonable range, the operation cost of the system is reduced, the energy consumption is reduced, and the annual comprehensive energy efficiency ratio is improved. In addition, the composite cabinet air conditioner has reasonable structural design, simple pipelines and material cost saving; the intelligent automatic control operation is convenient and fast in operation and maintenance.

Description

Refrigeration/heat pipe composite type cabinet air conditioning system and control method thereof

Technical Field

The invention relates to a cabinet temperature control device in the communication, power and industrial control industries. In particular to a refrigeration/heat pipe composite type cabinet air conditioning system and a control method thereof.

Background

The cabinet air conditioner is widely applied to the industries such as an outdoor communication cabinet, a base station, a storage battery cabinet, a charging pile, an industrial electrical control cabinet and the like, and the cabinet air conditioner used in the current domestic and foreign industries mainly comprises a cabinet shell, a compressor, an internal circulation fan, an external circulation fan, a condenser, an evaporator, a middle partition plate, a refrigerating system connecting pipeline and a control part. The working principle is as follows: after the air conditioner is powered on, low-pressure steam of a refrigerant in the refrigeration system is sucked by the compressor and compressed into high-pressure steam which is then discharged to the condenser, and meanwhile, air sucked by the fan outside the cabinet flows through the condenser to take away heat emitted by the refrigerant, so that the high-pressure refrigerant steam is condensed into high-pressure liquid. The high-pressure liquid passes through the throttling device and then is sprayed into the evaporator, and is evaporated under corresponding low pressure to absorb the surrounding heat. Meanwhile, the fan in the cabinet enables air to continuously pass through the fins of the evaporator for heat exchange, and the air which is cooled after heat release is sent into the cabinet. Therefore, the air in the cabinet continuously and circularly flows to achieve the aim of reducing the temperature.

Because the sensible heat load ratio of a machine room and a base station is large, and a cabinet air conditioner is a direct evaporative air conditioning system which operates in a refrigerating mode all the year around, even if the external environment temperature is very low, a compression type refrigerating system still needs to be operated to cool the machine room, the energy consumption all the year around is high, the operating cost is high, the starting and stopping loss of the refrigerating system is large, the service life of the machine is lost, and faults are prone to occur. Therefore, if the indoor and outdoor temperature difference can be utilized to provide cold energy (heat dissipation) for the indoor side at low cost, the annual energy consumption and the running cost of the air conditioning system can be greatly reduced, and the system energy efficiency is improved. The composite air conditioner applying heat pipe technology is one method of utilizing low temperature outdoor air to provide cold to indoor side. However, the existing refrigeration and heat pipe composite air conditioner generally has complex system design and multiple copper pipe branches, most products need two sets of independent pipelines and heat exchangers for refrigeration and heat pipe, and the material cost is high. Therefore, how to save materials and simultaneously achieve the purpose of improving the annual energy efficiency of the air conditioner by utilizing the outdoor low-temperature air to provide cold for the indoor side is a technical problem which needs to be solved by the technical personnel in the field at present.

Disclosure of Invention

The invention aims to solve the following problems in the prior art: how to utilize the system constructed by the same heat exchanger and pipeline can effectively utilize the outdoor natural cold source while saving materials, reduce energy consumption and save energy.

In order to solve the problems in the prior art, the invention provides a refrigeration/heat pipe composite type cabinet air conditioning system and a control method thereof.

Preferably, a refrigeration system connecting pipeline, a controller and a four-way valve are arranged in the cabinet shell, and the refrigeration system connecting pipeline is respectively connected with an exhaust port of the compressor, an inlet of the condenser, an outlet of the evaporator and a suction port of the compressor through the four-way valve.

Preferably, the outlet of the condenser and the inlet of the evaporator are connected through a throttling variable mechanism pipeline.

Preferably, the four-way valve is connected with an exhaust port of the compressor through an oil separator pipeline, and an oil return port of the oil separator is connected with the compressor through an oil return capillary tube.

Preferably, the four-way valve is connected with a suction port of the compressor through a gas-liquid separator pipeline.

Preferably, the throttle variable mechanism may also be a special valve such as a two-stage electronic expansion valve, a precision electric ball valve with adjustable opening degree, or other system components such as an electric ball valve and an electronic expansion valve, which are connected in an equivalent manner.

Preferably, the evaporator is arranged at the lowest end in the cabinet shell, and the position height of the evaporator is lower than the position height of the condenser and the throttling variable mechanism.

Preferably, the specific control method is as follows:

after the composite cabinet air conditioning unit receives the starting instruction and completes self-checking, the temperature Tin in the cabinet and the ambient temperature Tout outside the cabinet are detected through the sensors, and the temperature difference delta Ta between the inside and the outside of the cabinet is calculated by the controller to be Tin-Tout.

And when the temperature Tin in the cabinet is less than or equal to the set temperature Ts (such as 35 ℃) in the cabinet, the unit is in standby.

When the temperature Tin in the cabinet is larger than the set temperature Ts in the cabinet, selecting an operation mode according to the temperature difference delta Ta between the inside and the outside of the cabinet:

if the temperature difference delta Ta between the inside and the outside of the cabinet is large, and the delta Ta is larger than the delta Tmin (such as 20 ℃), the heat pipe heat dissipation mode of the unit operation can meet the requirements of energy conservation and cabinet cooling, until the temperature difference between the inside and the outside of the cabinet is small, the delta Ta is less than or equal to the delta Tmin, the heat pipe heat dissipation mode can not meet the requirements of cabinet cooling, the unit is switched to an air-conditioning refrigeration mode, the compressor is put into operation, the throttling mechanism throttles and reduces the pressure, the air outlet temperature in the cabinet is rapidly reduced, and the heating load in the cabinet can reliably work.

After the unit operates the air-conditioning refrigeration mode, until the temperature difference between the inside and the outside of the cabinet is changed to be large enough, the temperature delta Ta is larger than the temperature delta Tmax (for example, 30 ℃), the unit switches the heat pipe heat dissipation mode, and the temperature difference between the inside and the outside can meet the cooling requirement of the cabinet.

Therefore, the unit control module intelligently selects an operation mode according to the temperature difference delta Ta between the internal environment and the external environment, and gives consideration to the requirements of energy conservation and the temperature of the heating load in the cabinet until the temperature Tin in the cabinet is less than or equal to the set temperature Ts in the cabinet, and the unit is in standby.

(1) When the unit operates in an air-conditioning refrigeration mode, the valve core ball position of the four-way valve is switched to the following state under the excitation action of the coil: one path of the two paths of the valve core ball is communicated with an exhaust port of the compressor and an inlet of the condenser through the oil separator, the other path of the two paths of the valve core ball is communicated with an outlet of the evaporator and an air suction port of the compressor through the gas-liquid separator, the bypass branch is closed by the three-way valve and communicated with a branch where the electronic expansion valve is located, and the electronic expansion valve opens the opening degree with proper throttling action according to the superheat degree. The compressor runs, low-pressure vapor of the refrigerant is sucked by the compressor and compressed into high-pressure vapor which is then discharged to the condenser, meanwhile, air sucked by the external circulation fan flows through the condenser to take away heat emitted by the refrigerant, so that the high-pressure refrigerant vapor is condensed into high-pressure liquid, the high-pressure liquid is throttled and depressurized by the electronic expansion valve and then is sprayed into the evaporator and evaporated under corresponding low pressure, the ambient heat is sucked by the compressor again after being heated, and meanwhile, the air is continuously subjected to heat exchange by the internal circulation fan through fins of the evaporator, and the air which is cooled after heat exchange is sent into the cabinet;

(2) when the unit operates in a heat pipe radiating mode, the valve core ball position of the four-way valve is reset to the following state under the excitation action of the coil: one path of the two paths of the valve core ball is respectively communicated with an exhaust port and an air suction port of the compressor through the oil separator and the gas-liquid separator to enable the two paths to be in short circuit, the other path is communicated with an inlet of the condenser and an outlet of the evaporator to enable the condenser and the evaporator to form an independent heat pipe natural circulation system, the compressor stops, the three-way valve closes a branch where the electronic expansion valve is located, the bypass branch is opened to enable the whole throttling variable mechanism to have no throttling and pressure reducing effects and small local resistance, the requirement that the on-way resistance of a refrigerant is small according to the heat pipe natural circulation principle is met, the refrigerant in the evaporator continuously absorbs heat and evaporates at the moment, the gaseous refrigerant rises into the condenser to condense and release heat to form condensate, flows back to the evaporator through the fully-opened throttling variable mechanism without throttling effects under the action of gravity, a heat pipe natural circulation is completed, and meanwhile, the air in the cabinet continuously exchanges heat through fins of the evaporator through the internal circulation fan, and send the air that changes into cold after heat exchange to the cabinet; the external circulation fan continuously absorbs heat of air outside the cabinet through the fins of the condenser, the air which becomes hot after heat exchange is exhausted outside the cabinet, the operation is carried out in a reciprocating mode, the unit is in an effective heat pipe cooling state, and heat in the cabinet is transferred to the environment outside the cabinet through natural circulation of the heat pipes.

Compared with the prior art, the invention has the beneficial effects that:

the refrigeration/heat pipe composite type cabinet air-conditioning system and the control method thereof are provided with a four-way valve, a condenser, an external circulating fan, a throttling variable mechanism, a three-way valve, an electronic expansion valve, a compressor, an evaporator and an internal circulating fan, through the design, the device can realize the respective operation of the heat pipe system and the vapor compression refrigeration system according to different working conditions through an automatic control system, so that the system always operates in an energy-saving mode under different working conditions, the temperature in the cabinet is ensured to be in a reasonable range, the operation cost of the system is reduced, the energy consumption is reduced, the annual comprehensive energy efficiency ratio is improved, in addition, the composite type cabinet air-conditioning system is reasonable in structural design, the pipeline is simple, and the material cost is saved; the intelligent automatic control operation is convenient and fast in operation and maintenance.

Drawings

FIG. 1 is a schematic diagram of the cooling mode of the air conditioner of the present invention;

FIG. 2 is a schematic diagram of a heat pipe heat dissipation mode of the present invention;

FIG. 3 is a schematic view of a first alternative form of the preferred throttling mechanism of the present invention;

FIG. 4 is a schematic view of a second alternative form of the preferred throttling mechanism of the present invention;

FIG. 5 is a flow chart illustrating a control method according to the present invention.

In the figure: 1. a four-way valve; 2. a condenser; 3. an external circulation fan; 4. a throttle variable mechanism; 5. a three-way valve; 6. an electronic expansion valve; 7. a compressor; 8. an evaporator; 9. an internal circulation fan; 10. an oil separator; 11. an oil return capillary tube; 12. a gas-liquid separator. (arrows in the figure represent the direction of flow of refrigerant)

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

As shown in fig. 1-5, the drawings are assembled from:

assembly description: the condenser 2, the external circulation fan 3, the throttling variable mechanism 4, the three-way valve 5, the electronic expansion valve 6, the compressor 7, the evaporator 8 and the internal circulation fan 9 are all installed inside the cabinet shell, then the refrigeration system connecting pipeline, the controller and the four-way valve 1 are installed inside the cabinet shell, the refrigeration system connecting pipeline is respectively connected with an exhaust port of the compressor 7, an inlet of the condenser 2, an outlet of the evaporator 8 and an air suction port of the compressor 7 through the four-way valve 1, then the inlet of the three-way valve 5 is connected with the outlet of the condenser 2 through a pipeline, one outlet of the three-way valve 5 is connected to the inlet of the evaporator 8 in series through the electronic expansion valve 6, and the other outlet of the three-way valve 5 is directly bypassed to the inlet of the evaporator 8 through a pipeline.

Example two

As shown in fig. 1-5, the drawings are assembled from:

assembly description: the condenser 2, the external circulating fan 3, the throttle variable mechanism 4, the compressor 7, the evaporator 8, the internal circulating fan 9, the oil separator 10 and the gas-liquid separator 12 are all installed inside a cabinet shell, then a refrigerating system connecting pipeline, a controller and the four-way valve 1 are installed inside the cabinet shell, the refrigerating system connecting pipeline is respectively connected with an air outlet of the oil separator 10, an inlet of the condenser 2, an outlet of the evaporator 8 and an inlet of the gas-liquid separator 12 through the four-way valve 1, the air outlet of the oil separator 10 is connected with an air outlet of the compressor 7 through a pipeline, an oil return port of the oil separator 10 is connected with the compressor 7 through an oil return capillary tube 11, an outlet of the gas-liquid separator 12 is connected with an air suction port of the compressor 7 through a pipeline, and then an outlet of the condenser 2 is connected with an inlet of the evaporator 8 through a throttle variable mechanism 4 through a pipeline.

When the unit is switched from the air-conditioning refrigeration mode to the heat pipe heat dissipation mode, the action time sequence of each part is as follows: the throttling mechanism 4 is fully closed, the unit refrigerant is recovered into the condenser 2 under the drive of the compressor 7, after a period of time t, the valve core ball position of the four-way valve 1 is switched to a heat pipe radiating state from an air conditioner refrigerating state, the compressor 7 stops, the throttling variable mechanism 4 is fully opened, and the inner circulating fan 9 and the outer circulating fan 3 automatically adjust the rotating speed according to a heat pipe radiating load program. The time t for recovering the refrigerant is intelligently controlled by the control module according to the amount of the refrigerant required by the heat load of the heat pipe heat dissipation mode.

When the unit is switched from the heat pipe heat dissipation mode to the air conditioner refrigeration mode, the action time sequence of each part is as follows: the valve core ball position of the four-way valve 1 is switched to an air conditioner refrigeration state from a heat pipe heat dissipation state, the throttle variable mechanism 4 is reset and then opened to an initial opening according to an air conditioner refrigeration logic, the rotating speed of the inner circulating fan 9 and the outer circulating fan 3 is automatically adjusted by a program according to the heat load, the compressor 7 is started, and then all parts of the unit run according to the air conditioner refrigeration logic.

FIG. 3 is a two-stage electronic expansion valve, which is adjusted at a smaller opening in the air conditioning cooling mode to throttle and depressurize the refrigerant; in a heat pipe heat dissipation mode, the valve is fully opened, the drift diameter is reasonable, the local resistance is extremely low, and the requirement that the on-way resistance of the refrigerant is small according to the heat pipe natural circulation principle is met.

FIG. 4 is a precision electric ball valve with adjustable opening, which in air conditioner cooling mode, functions to precisely adjust the refrigerant flow through the structural notches at a smaller opening; in a heat pipe heat dissipation mode, the valve is fully opened, and the requirement that the refrigerant has small on-way resistance under the heat pipe natural circulation principle is met.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and the preferred embodiments of the present invention are described in the above embodiments and the description, and are not intended to limit the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A refrigeration/heat pipe composite type cabinet air conditioning system and a control method thereof comprise a cabinet shell, and are characterized in that: inside condenser (2), outer circulating fan (3), compressor (7), inner circulating fan (9) and the variable mechanism of throttle (4) of being provided with of rack shell, the variable mechanism of throttle (4) are including three-way valve (5) and electronic expansion valve (6), the export of tube coupling condenser (2) is passed through in the import of three-way valve (5), and an export of three-way valve (5) is established ties to the import of evaporimeter (8) by electronic expansion valve (6), and another export of three-way valve (5) is through the import of the direct bypass of pipeline to evaporimeter (8), evaporimeter (8) set up in the inside bottom of rack shell, and its position height is less than the position height of condenser (2) and the variable mechanism of throttle (4).

2. The cooling/heat pipe composite type cabinet air-conditioning system and the control method thereof according to claim 1, wherein: a refrigerating system connecting pipeline, a controller and a four-way valve (1) are arranged in the cabinet shell, and the refrigerating system connecting pipeline is respectively connected with an exhaust port of a compressor (7), an inlet of a condenser (2), an outlet of an evaporator (8) and an air suction port of the compressor (7) through the four-way valve (1).

3. The refrigeration/heat pipe composite type cabinet air-conditioning system and the control method thereof according to claim 1, wherein: the outlet of the condenser (2) is connected with the inlet of the evaporator (8) through a throttling variable mechanism (4) by a pipeline.

4. A cooling/heat pipe composite type cabinet air conditioning system and a control method thereof as claimed in claims 1 and 2, wherein: an oil separator (10) can be additionally arranged between the four-way valve (1) and the compressor (7), the exhaust ports of the four-way valve (1) and the compressor (7) are connected through a pipeline of the oil separator (10), and the oil return port of the oil separator (10) is connected with the compressor (7) through an oil return capillary tube (11).

5. A cooling/heat pipe composite type cabinet air conditioning system and a control method thereof as claimed in claims 1 and 2, wherein: a gas-liquid separator (12) can be additionally arranged between the four-way valve (1) and the compressor (7), and the air suction ports of the four-way valve (1) and the compressor (7) are connected through a pipeline of the gas-liquid separator (12).

6. The refrigeration/heat pipe composite type cabinet air-conditioning system and the control method thereof according to claim 1, characterized in that: the throttling variable mechanism (4) can also be special valve parts such as a two-section electronic expansion valve (6) and an opening-adjustable precision electric ball valve, and can also be other system parts such as an electric ball valve and the electronic expansion valve (6) which are connected according to an equivalent form.

7. The refrigeration/heat pipe composite type cabinet air-conditioning system and the control method thereof as claimed in any one of claims 1 to 6, wherein the specific control method is as follows:

if the temperature difference delta Ta between the inside and the outside of the cabinet is large, and the delta Ta is larger than the delta Tmin (such as 20 ℃), the heat pipe heat dissipation mode of the unit operation gives consideration to energy saving and cabinet cooling requirements, until the temperature difference between the inside and the outside of the cabinet changes to be small, the delta Ta is less than or equal to the delta Tmin, the heat pipe heat dissipation mode cannot meet the cabinet cooling requirements, the unit is switched to an air conditioning refrigeration mode, the compressor (7) is put into operation, the throttling mechanism throttles and reduces the pressure, the air outlet temperature in the cabinet is rapidly reduced, and the heating load in the cabinet can reliably work.

Therefore, the unit control module intelligently selects an operation mode according to the temperature difference delta Ta between the inside and the outside of the cabinet, and gives consideration to the requirements of energy conservation and the temperature of the heating load in the cabinet until the temperature Tin in the cabinet is less than or equal to the set temperature Ts in the cabinet, and the unit is in standby.

(1) When the unit runs the air-conditioning refrigeration mode, the valve core ball position of the four-way valve 1 is turned to the following state under the excitation of the coil: one path of the two paths of the valve core ball is communicated with an exhaust port of the compressor (7) and an inlet of the condenser (2) through the oil separator (10), the other path of the two paths of the valve core ball is communicated with an outlet of the evaporator (8) and an air suction port of the compressor (7) through the gas-liquid separator (12), the bypass branch is closed by the three-way valve (5) and communicated with a branch where the electronic expansion valve (6) is located, and the electronic expansion valve (6) opens with proper opening degree of throttling action according to superheat degree. The compressor (7) runs, low-pressure steam of a refrigerant is sucked by the compressor (7) and compressed into high-pressure steam which is then discharged to the condenser (2), meanwhile, air sucked by the outer circulating fan (3) flows through the condenser (2) to take away heat released by the refrigerant, so that the high-pressure refrigerant steam is condensed into high-pressure liquid, the high-pressure liquid is throttled and depressurized by the electronic expansion valve (6) and then is sprayed into the evaporator (8) and evaporated under corresponding low pressure, the surrounding heat is sucked by the compressor (7) again after being heated, meanwhile, the air is continuously subjected to heat exchange through fins of the evaporator (8) by the inner circulating fan (9), and the air which is cooled after heat exchange is sent into the cabinet;

(2) when the unit operates in a heat pipe heat radiation mode, the valve core ball position of the four-way valve (1) is reset to the following state under the excitation action of the coil: one path of the two paths of the valve core ball is respectively communicated with an exhaust port and an air suction port of a compressor (7) through an oil separator (10) and a gas-liquid separator (12) to be in short circuit, the other path of the two paths is communicated with an inlet of a condenser (2) and an outlet of an evaporator (8) to form an independent heat pipe natural circulation system by the condenser (2) and the evaporator (8), the compressor (7) stops, a three-way valve (5) closes a branch where an electronic expansion valve (6) is located, a bypass branch is opened to enable the whole throttling variable mechanism (4) to have no throttling and pressure reducing effects and small local resistance, the requirement that the refrigerant along the path resistance is small in the heat pipe natural circulation principle is met, at the moment, the refrigerant in the evaporator (8) continuously absorbs heat and evaporates, the gaseous refrigerant rises to the condenser (2) to condense and release heat to form condensate, and flows back to the evaporator (8) through the fully-opened throttling variable mechanism (4) without throttling effects under the action of gravity, finishing natural circulation of a heat pipe, simultaneously enabling air in the cabinet to continuously carry out heat exchange through the fins of the evaporator (8) by the internal circulation fan (9), and sending the air which is changed into cold after heat exchange into the cabinet; the external circulation fan (3) continuously absorbs heat of air outside the cabinet through the fins of the condenser (2), and exhausts the heated air after heat exchange to the outside of the cabinet, so that the air exchange is carried out in a reciprocating mode, the unit is in an effective heat pipe cooling state, and heat in the cabinet is transferred to the environment outside the cabinet through natural circulation of the heat pipes.