CN114710932B

CN114710932B - A control method for refrigeration/heat pipe composite cabinet air conditioner

Info

Publication number: CN114710932B
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: 2025-02-25
Anticipated expiration: 2042-03-29
Also published as: CN114710932A

Abstract

The present invention relates to the technical field of cabinet temperature control equipment in the communication, electric power, and industrial control industries, and specifically to a refrigeration/heat pipe composite cabinet air conditioner control method, including a cabinet shell, a condenser, an external circulation fan, a compressor, an evaporator, an internal circulation fan, and a throttling variable mechanism are arranged inside the cabinet shell, and the throttling variable mechanism includes a three-way valve and an electronic expansion valve. The present invention realizes the automatic 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 the energy-saving mode under its different working conditions, and ensures that the temperature in the cabinet is within a reasonable range, while reducing the operating cost of the system, reducing energy consumption, and improving the comprehensive energy efficiency ratio throughout the year. In addition, the composite cabinet air conditioner has a reasonable structural design, simple piping, and saves material costs; it has intelligent automatic control operation and convenient operation and maintenance.

Description

Control method for air conditioner of refrigerating/heat pipe composite cabinet

Technical Field

The invention relates to cabinet temperature control equipment in the communication, power and industrial control industries. In particular to a control method of a refrigerating/heat pipe compound cabinet air conditioner.

Background

The cabinet air conditioner has wide application in the industries of outdoor communication cabinets, base stations, storage battery cabinets, charging piles, industrial electrical control cabinets and the like, and the cabinet air conditioner used in the domestic and foreign industries at present mainly comprises a cabinet shell, a compressor, an inner circulating fan, an outer circulating fan, a condenser, an evaporator, a middle partition plate, a refrigerating system connecting pipeline and a control part. The working principle of the air conditioner is that after the air conditioner is electrified, low-pressure vapor of the refrigerant in the refrigerating system is sucked by the compressor and compressed into high-pressure vapor and 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 vapor is condensed into high-pressure liquid. The high-pressure liquid is sprayed into the evaporator after passing through the throttling device and is evaporated under the corresponding low pressure, and the surrounding heat is extracted. Meanwhile, the fan in the cabinet makes air continuously pass through the fins of the evaporator to exchange heat, and sends the cooled air after heat release into the cabinet. The air in the cabinet continuously circulates and flows, so that the aim of reducing the temperature is fulfilled.

Because the sensible heat load ratio of the machine room and the base station is large, and the cabinet air conditioner is a direct evaporative air conditioning system which is operated in a refrigerating mode all the year round, the compression refrigerating system still needs to be operated continuously to cool the machine room even when the external environment temperature is very low, so that the energy consumption is high all the year round, the operation cost is high, the start-stop loss of the refrigerating system is large, the service life of the machine is lost, and faults are easy to occur. Therefore, if the indoor and outdoor temperature difference can be utilized to provide cold (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 energy efficiency of the system can be improved. The composite air conditioner using heat pipe technology is one method of providing cold for indoor side with outdoor low temperature air. However, the conventional refrigeration and heat pipe composite air conditioner is complex in general system design, more in copper pipe branches, and high in material cost, and most of products are refrigeration and heat pipes which need two independent pipelines and heat exchangers. Therefore, how to save materials and simultaneously realize the purpose of improving the annual energy efficiency of the air conditioner by using the outdoor low-temperature air to provide cold for the indoor side is a technical problem which needs to be solved by the person skilled in the art at present.

Disclosure of Invention

The invention aims to solve the following problems in the prior art how to utilize a system with the same set of heat exchanger and pipeline structure, so that the material is saved, the outdoor natural cold source can be effectively utilized, the energy consumption is reduced, and the energy is saved.

The invention provides a control method of a refrigerating/heat pipe compound cabinet air conditioner, which solves the problems existing in the prior art and comprises a cabinet shell, wherein a condenser, an external circulation fan, a compressor, an evaporator, an internal circulation fan and a throttling variable mechanism are arranged in the cabinet shell, the throttling variable mechanism comprises a three-way valve and an electronic expansion valve, an inlet of the three-way valve is connected with an outlet of the condenser through a pipeline, one outlet of the three-way valve is connected with an inlet of the evaporator in series through the electronic expansion valve, and the other outlet of the three-way valve is directly bypassed to the inlet of the evaporator through the pipeline.

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

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

Preferably, the throttle variable mechanism can also be special valve members such as a two-section electronic expansion valve, an opening-adjustable precision electric ball valve and the like, and can also be other system members such as the electric ball valve, the electronic expansion valve and the like which are connected in an equivalent mode.

Preferably, the evaporator is arranged at the bottommost end inside the cabinet shell, and the position height of the evaporator is lower than the position height of the condenser and the throttle 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 temperature Tout outside the cabinet are detected through the sensor, and the controller calculates the temperature difference delta Ta=tin-Tout between the environment inside and outside the cabinet.

When the temperature Tin in the cabinet is less than or equal to the set temperature (target temperature) Ts (such as 35 ℃), the unit stands by.

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

If the temperature difference delta Ta between the inner environment and the outer environment of the cabinet meets delta Ta > delta Tmin (such as 20 ℃), the heat pipe heat dissipation mode of the unit operation gives consideration to energy conservation and cabinet cooling requirements until the temperature difference change between the inner environment and the outer environment of the cabinet meets delta Ta less than or equal to delta Tmin, the heat pipe heat dissipation mode cannot meet the cabinet cooling requirements, at the moment, the unit is switched into an air conditioner 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 is enabled to reliably work.

After the unit operates the air conditioner refrigerating mode, until the temperature difference change of the environment inside and outside the cabinet meets delta Ta > delta Tmax (such as 30 ℃), the unit switches the heat pipe radiating mode, and the temperature difference of the inside and outside is enough to 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 energy conservation and the heating load temperature requirement in the cabinet, and the unit stands by until the temperature Tin in the cabinet is less than or equal to the set temperature Ts in the cabinet.

When the unit runs in the air conditioner refrigerating mode, the valve core ball position of the four-way valve is changed to the following state under the excitation action of a coil, one path of the valve core ball is communicated with the exhaust port of the compressor and the inlet of the condenser through the oil separator, the other path of the valve core ball is communicated with the outlet of the evaporator and the air suction port of the compressor through the gas-liquid separator, the three-way valve closes the bypass branch and is communicated with the branch where the electronic expansion valve is located, and the electronic expansion valve opens a proper opening degree for throttling action according to the superheat degree. The compressor operates, low-pressure vapor of the refrigerant is sucked by the compressor and compressed into high-pressure vapor and then discharged to the condenser, meanwhile, air sucked by the external circulation fan flows through the condenser to take away heat released 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, the high-pressure liquid is evaporated at a corresponding low pressure, the surrounding heat is sucked again by the compressor 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 cooled air after heat exchange is sent into the cabinet;

When the heat pipe heat dissipation mode is operated by the unit, the valve core ball position of the four-way valve is reset to the state under the coil excitation action, one path of the valve core ball is communicated with an air outlet and an air suction port of the compressor through the oil separator and the gas-liquid separator respectively, so that the two paths are in short connection, the other path of the valve core ball is communicated with an inlet of the condenser and an outlet of the evaporator, the condenser and the evaporator form an independent heat pipe natural circulation system, the compressor is stopped, the three-way valve closes a branch where the electronic expansion valve is located, the bypass branch is opened, the whole throttling variable mechanism has no throttling and depressurization effects, the local resistance is small, the requirement of the heat pipe natural circulation principle that the refrigerant is small in the path resistance is met, at the moment, the refrigerant in the evaporator continuously absorbs heat and evaporates, gaseous refrigerant is heated to be condensed and released into condensate under the action of gravity, the condensate flows back to the evaporator through the throttling variable mechanism which has no throttling effect, the inner circulation fan enables air in the cabinet to continuously exchange heat through fins of the evaporator, and the cooled air is sent into the cabinet, the cabinet is enabled to pass through the fins of the heat exchange heat exchanger, the cabinet is enabled to be heated, the heat pipe natural circulation air is cooled, and the heat is effectively transferred to the heat pipe heat is supplied to the outside of the heat pipe unit, and the heat pipe is cooled by the heat exchanger, and the heat pipe is circulated outside the cabinet.

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

The refrigerating/heat pipe compound 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, by the design, the device can realize the respective operation of the heat pipe system and the vapor compression refrigerating 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, and in addition, the compound cabinet air conditioning system is reasonable in structural design, simple in pipeline, saves the material cost, and is convenient to operate in an intelligent self-control mode.

Drawings

FIG. 1 is a schematic diagram of an air conditioning refrigeration mode of the present invention;

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

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

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

FIG. 5 is a flow chart of the control method of 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 and a gas-liquid separator. (arrows in the figure represent the flow direction of the refrigerant)

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

As shown in fig. 1-5, the assembly is illustrated as being made up of the following components:

The assembly description is that a condenser 2, an external circulation fan 3, a throttle variable mechanism 4, a three-way valve 5, an electronic expansion valve 6, a compressor 7, an evaporator 8 and an internal circulation fan 9 are all arranged in a cabinet shell, a refrigerating system connecting pipeline, a controller and a four-way valve 1 are arranged in the cabinet shell, the refrigerating 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, an inlet of the three-way valve 5 is connected with an outlet of the condenser 2 through a pipeline, one outlet of the three-way valve 5 is connected with an 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 an inlet of the evaporator 8 through a pipeline.

Example two

The assembly description includes that a condenser 2, an external circulation fan 3, a throttling variable mechanism 4, a compressor 7, an evaporator 8, an internal circulation fan 9, an oil separator 10 and a gas-liquid separator 12 are all arranged in a cabinet shell, a refrigerating system connecting pipeline, a controller and a four-way valve 1 are arranged in 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, an air outlet of the oil separator 10 is connected with an air outlet of the compressor 7 through pipelines, an oil return port of the oil separator 10 is connected with the compressor 7 through an oil return capillary 11, an outlet of the gas-liquid separator 12 is connected with an air suction port of the compressor 7 through a pipeline, and an outlet of the condenser 2 is connected with an inlet of the evaporator 8 through a pipeline of the throttling variable mechanism 4.

When the unit is switched from the air-conditioning refrigeration mode to the heat pipe heat dissipation mode, the operation time sequence of each component is that the throttle variable 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 from the air-conditioning refrigeration state to the heat pipe heat dissipation state, the compressor 7 is stopped, the throttle variable mechanism 4 is fully opened, and the rotation speed of the inner circulating fan 9 and the outer circulating fan 3 is automatically adjusted according to a heat pipe heat dissipation load program. The time t for recovering the refrigerant is intelligently controlled by the control module according to the quantity of the refrigerant required by the heat load of the heat pipe heat radiation mode.

When the unit is switched from the heat pipe heat radiation mode to the air conditioner refrigeration mode, the action time sequence of each component is that the valve core ball position of the four-way valve 1 is switched from the heat pipe heat radiation state to the air conditioner refrigeration state, the throttle variable mechanism 4 is reset and then is opened to the initial opening according to the air conditioner refrigeration logic, the inner circulation fan 9 and the outer circulation fan 3 automatically regulate the rotating speed according to the heat load by a program, the compressor 7 is started, and then each component of the unit operates according to the air conditioner refrigeration logic.

FIG. 3 shows a two-stage electronic expansion valve, in which the valve is regulated at a smaller opening degree to throttle and depressurize the refrigerant in the air-conditioning refrigeration mode, and in which the valve is fully opened, the diameter is reasonable, the local resistance is extremely small, and the requirement of small resistance along the refrigerant path of the heat pipe natural circulation principle is met in the heat pipe heat dissipation mode.

Fig. 4 shows an opening-adjustable precision electric ball valve, in which the valve plays a role in precisely adjusting the flow rate of the refrigerant through structural notch grooves under a smaller opening degree in an air-conditioning refrigeration mode, and in which the valve is fully opened in a heat pipe heat dissipation mode, so as to meet the requirement of small resistance of the refrigerant along the natural circulation principle of the heat pipe.

The foregoing has shown and described the basic principles, principal 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 above-described embodiments, and that the above-described embodiments and descriptions are only preferred embodiments of the present invention, and are not intended to limit the invention, and that various changes and modifications may be made therein without departing from the spirit and scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A control method for a refrigeration/heat pipe composite cabinet air conditioner, comprising a cabinet shell, characterized in that: a condenser (2), an external circulation fan (3), a compressor (7), an internal circulation fan (9) and a throttling variable mechanism (4) are arranged inside the cabinet shell, the throttling variable mechanism (4) comprising a three-way valve (5) and an electronic expansion valve (6), the inlet of the three-way valve (5) is connected to the outlet of the condenser (2) through a pipeline, one outlet of the three-way valve (5) is connected in series to the inlet of an evaporator (8) by 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, and the evaporator (8) is arranged at the bottom end inside the cabinet shell, and its position height is lower than the position height of the condenser (2) and the throttling variable mechanism (4);

A refrigeration system connecting pipeline, a controller and a four-way valve (1) are arranged inside the cabinet shell, and the refrigeration system connecting pipeline is respectively connected to the exhaust port of the compressor (7), the inlet of the condenser (2), the outlet of the evaporator (8) and the air intake port of the compressor (7) through the four-way valve (1);

The outlet of the condenser (2) and the inlet of the evaporator (8) are connected via a throttling variable mechanism (4) pipeline;

An oil separator (10) is added between the four-way valve (1) and the compressor (7); the exhaust port of the four-way valve (1) and the compressor (7) are connected via a pipeline of the oil separator (10); and the oil return port of the oil separator (10) and the compressor (7) are connected via an oil return capillary (11);

A gas-liquid separator (12) is added between the four-way valve (1) and the compressor (7), and the four-way valve (1) and the air intake port of the compressor (7) are connected via a pipeline of the gas-liquid separator (12);

The specific control methods are as follows:

After the composite cabinet air conditioner unit receives the start command and completes the self-test, it detects the cabinet temperature Tin and the external environment temperature Tout through the sensor, and the controller calculates the internal and external environment temperature difference ΔTa = Tin-Tout;

When the cabinet temperature Tin ≤ the cabinet set temperature Ts, Ts is 35℃, the unit is on standby;

When the temperature inside the cabinet Tin> the set temperature inside the cabinet Ts, select the operation mode according to the temperature difference ΔTa between the inside and outside of the cabinet:

If the temperature difference ΔTa between the inside and outside of the cabinet satisfies ΔTa＞ΔTmin, and ΔTmin is 20°C, the unit operates in a heat pipe cooling mode to take into account both energy saving and cabinet cooling requirements, until the temperature difference between the inside and outside of the cabinet satisfies ΔTa≤ΔTmin, and the heat pipe cooling mode cannot meet the cabinet cooling requirement. At this time, the unit switches to an air conditioning cooling mode, the compressor (7) starts working, and the throttling mechanism throttles and reduces the pressure, quickly reducing the air outlet temperature in the cabinet, so that the heating load in the cabinet can work reliably;

After the unit runs in the air conditioning cooling mode, until the temperature difference between the inside and outside of the cabinet satisfies ΔTa＞ΔTmax, ΔTmax is 30°C, the unit switches to the heat pipe cooling mode. At this time, the temperature difference between the inside and outside is sufficient to meet the cabinet cooling requirements;

In this way, the unit control module intelligently selects the operating mode according to the temperature difference ΔTa between the inside and outside of the cabinet, taking into account energy saving and the temperature requirements of the heating load in the cabinet. When the temperature in the cabinet Tin ≤ the set temperature in the cabinet Ts, the unit will be in standby mode.

When the unit is operating in the air conditioning refrigeration mode, the valve core ball position of the four-way valve (1) is transferred to the following state under the action of the coil excitation: one of the two paths of the valve core ball passes through the oil separator (10) to connect the compressor (7) exhaust port and the condenser (2) inlet, and the other path passes through the gas-liquid separator (12) to connect the evaporator 8 outlet and the compressor (7) suction port. The three-way valve (5) closes the bypass branch and connects the branch where the electronic expansion valve (6) is located. The electronic expansion valve (6) opens the throttling function to an appropriate opening according to the superheat. The compressor (7) is running, and the low-pressure vapor of the refrigerant is compressed. The compressor (7) sucks in and compresses the refrigerant into high-pressure vapor and then discharges it to the condenser (2). At the same time, the air sucked in by the external circulation fan (3) flows through the condenser (2), takes away the heat released by the refrigerant, and condenses the high-pressure refrigerant vapor into a high-pressure liquid. The high-pressure liquid is throttled and depressurized by the electronic expansion valve (6) and then sprayed into the evaporator (8), where it evaporates at a corresponding low pressure, absorbs the surrounding heat and heats up before being sucked in again by the compressor (7). At the same time, the internal circulation fan (9) causes the air to continuously pass through the fins of the evaporator (8) for heat exchange, and sends the air that has become cold after the heat exchange into the cabinet.

When the unit operates in the heat pipe cooling mode, the valve core ball position of the four-way valve (1) is reset to the following state under the action of the coil excitation: one of the two paths of the valve core ball passes through the oil separator (10) and the gas-liquid separator (12) to connect to the exhaust port and the air intake port of the compressor (7) respectively, so that they are short-circuited, and the other path connects to the inlet of the condenser (2) and the outlet of the evaporator (8), so that the condenser (2) and the evaporator (8) form an independent heat pipe natural circulation system, the compressor (7) stops, the three-way valve (5) closes the branch where the electronic expansion valve (6) is located, and the bypass branch is opened so that the entire throttling variable mechanism (4) has no throttling and pressure reduction effect, and the local resistance is small, which meets the requirement of the heat pipe natural circulation principle that the refrigerant resistance along the way is small. At this time The refrigerant in the evaporator (8) will continuously absorb heat and evaporate, and the gaseous refrigerant will rise to the condenser (2) to condense and release heat to become condensate, and under the action of gravity, it will flow back to the evaporator (8) through the fully open throttling variable mechanism (4) without throttling effect, completing a heat pipe natural circulation. At the same time, the internal circulation fan (9) allows the air in the cabinet to continuously pass through the fins of the evaporator (8) for heat exchange, and sends the air that has become cold after the heat exchange into the cabinet; the external circulation fan (3) allows the air outside the cabinet to continuously pass through the fins of the condenser (2) for heat absorption, and discharges the air that has become hot after the heat exchange to the outside of the cabinet. This reciprocating process is carried out, and the unit is in an effective heat pipe cooling state, and the heat in the cabinet is transferred to the environment outside the cabinet through the natural circulation of the heat pipe.