CN110749038A - Anti-freezing control system of high-temperature air conditioner - Google Patents

Anti-freezing control system of high-temperature air conditioner Download PDF

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Publication number
CN110749038A
CN110749038A CN201910967800.3A CN201910967800A CN110749038A CN 110749038 A CN110749038 A CN 110749038A CN 201910967800 A CN201910967800 A CN 201910967800A CN 110749038 A CN110749038 A CN 110749038A
Authority
CN
China
Prior art keywords
compressor
temperature
pressure controller
coil
evaporator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201910967800.3A
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Chinese (zh)
Inventor
孙英
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hefei Swan Refrigeration Technology Co Ltd
Original Assignee
Hefei Swan Refrigeration Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hefei Swan Refrigeration Technology Co Ltd filed Critical Hefei Swan Refrigeration Technology Co Ltd
Priority to CN201910967800.3A priority Critical patent/CN110749038A/en
Publication of CN110749038A publication Critical patent/CN110749038A/en
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/41—Defrosting; Preventing freezing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • F24F11/64—Electronic processing using pre-stored data
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/86—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling compressors within refrigeration or heat pump circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/88—Electrical aspects, e.g. circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
    • F25B43/006—Accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2140/00—Control inputs relating to system states
    • F24F2140/10—Pressure
    • F24F2140/12—Heat-exchange fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2140/00—Control inputs relating to system states
    • F24F2140/20—Heat-exchange fluid temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00—Problems to be solved
    • F25B2500/28—Means for preventing liquid refrigerant entering into the compressor

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Signal Processing (AREA)
  • Mathematical Physics (AREA)
  • Fuzzy Systems (AREA)
  • Analytical Chemistry (AREA)
  • Power Engineering (AREA)
  • Air Conditioning Control Device (AREA)

Abstract

The invention discloses an anti-freezing control system of a high-temperature air conditioner, which is used for a refrigeration loop consisting of a compressor, a condenser, a liquid storage device, a filter, an expansion valve and an evaporator and comprises a freezing point protector, a high-pressure controller and a low-pressure controller, the temperature measuring device comprises an alternating current contactor of a compressor, a time relay and a temperature sensing probe of a freezing point protector, wherein the temperature measuring probe of the freezing point protector measures the temperature of an evaporator coil, a high-voltage pressure controller and a low-voltage pressure controller are respectively installed at an exhaust end and an air return end of the compressor, contacts of the high-voltage pressure controller and the low-voltage pressure controller, a power-on delay closing contact of the time relay and an alternating current contactor coil of the compressor are sequentially connected in series to form a first series branch, two ends of the first series branch are respectively externally connected with a power supply, a coil of the time relay and a contact of the freezing point protector are connected in series to form a second series branch. The invention enables the high-temperature air conditioner to run in low-temperature refrigeration, and realizes a high-temperature and low-temperature integrated machine.

Description

Anti-freezing control system of high-temperature air conditioner
Technical Field
The invention relates to the field of high-temperature air-conditioning systems, in particular to an anti-freezing control system of a high-temperature air conditioner.
Background
The vehicle-mounted and airborne carrying equipment for executing transportation, communication, detection and other tasks, and equipment rooms of industry, power plants, oil drilling platforms and other equipment usually work in high-temperature environments, and need to be matched with a special high-temperature air conditioner suitable for the working environment to control the temperature of the equipment. When the ambient temperature (usually below 18 ℃) is low, the heat of the cooled cabin heating element is large, and air-conditioning refrigeration is still needed to cool the machine room and the cabin. When a conventional high-temperature air conditioner product works at normal temperature, the high-temperature air conditioner can be adjusted through the liquid storage tank, but when the ambient temperature is lower, the evaporator can be frosted and frozen by continuously refrigerating, even the liquid impact damage of the compressor can be caused, and the normal use of the unit is influenced.
Therefore, when the high-temperature air conditioner operates in low-temperature refrigeration, namely the high-temperature air conditioner can reliably work under the low-temperature refrigeration working condition, a reliable refrigeration system must be designed and control measures adapted to the reliable refrigeration system must be adopted.
The invention aims to provide an anti-freezing control system of a high-temperature air conditioner, which aims to solve the problem that a compressor is damaged by liquid impact during the operation of a high-temperature air conditioning system in the prior art.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the utility model provides a high temperature air conditioner prevents frostbite control system for the closed cycle refrigeration circuit that constitutes by compressor, condenser, reservoir, filter, expansion valve, evaporimeter which characterized in that: comprises a freezing point protector, a high-pressure controller, a low-pressure controller, an alternating current contactor of a compressor and a time relay, the temperature sensing probe of the freezing point protector is in contact with a coil of the evaporator to measure the temperature of the evaporator coil, the high-pressure controller is installed on a pipeline at the exhaust end of the compressor, the low-pressure controller is installed on a pipeline at the air return end of the compressor, a contact of the high-pressure controller, a contact of the low-pressure controller, a power-on delay closing contact of the time relay and an alternating current contactor coil of the compressor are sequentially connected in series to form a first series branch, the power-on delay closing contact of the time relay and the alternating current contactor coil of the compressor in the first series branch form a compressor control section, two ends of the first series branch are respectively connected with an external power supply, a coil of the time relay and a contact of the freezing point protector are connected in series to form a second series branch, and the second series.
The anti-freezing control system of the high-temperature air conditioner is characterized in that: the closed circulation refrigeration loop is formed by connecting the exhaust end of the compressor with the inlet end of the condenser through a pipeline, communicating the outlet end of the condenser with the interior of the liquid storage device through a pipeline, connecting the interior of the liquid storage device with the inlet end of the filter through a pipeline, connecting the outlet end of the filter with the inlet end of the expansion valve through a pipeline, connecting the outlet end of the expansion valve with the inlet end of the evaporator through a pipeline, and connecting the outlet end of the evaporator with the air return end of the compressor through a pipeline.
The anti-freezing control system of the high-temperature air conditioner is characterized in that: the closed cycle refrigeration loop is circulated with R134a high-temperature environment-friendly refrigerant.
The anti-freezing control system of the high-temperature air conditioner is characterized in that: the coil pipe of the evaporator is provided with a temperature sensing copper sleeve, the pipe wall of the temperature sensing copper sleeve is welded on the pipe wall of the coil pipe of the evaporator, and a temperature sensing probe of the freezing point protector is inserted into the temperature sensing copper sleeve from the pipe orifice of the temperature sensing copper sleeve.
The invention adopts the way that the liquid storage device is arranged at the outlet of the condenser so as to improve the applicability of the system; the temperature sensing copper sleeve is welded on the evaporator coil, the temperature sensing probe of the freezing point protector is inserted to sense the temperature of the evaporator coil, and the start and stop of the compressor are controlled through the freezing point protector contact, so that frost (ice) on the evaporator can be dissolved in time, the damage of the compressor caused by liquid impact is prevented, and the compressor is ensured to be restarted for more than 3min interval time through the time delay contact of the time relay.
The invention has the beneficial effects that:
1. by designing a reliable refrigerating system and adopting control measures suitable for the refrigerating system, the high-temperature air conditioner can run at low temperature for refrigeration, and the high-temperature and low-temperature integrated machine is realized.
2. The method is characterized in that a liquid storage device is arranged at an outlet of a condenser of an air-conditioning refrigeration system; a temperature sensing copper sleeve is welded on an evaporator coil, a temperature sensing probe of an ice point protector is inserted to sense the temperature of the evaporator coil, the start and stop of a compressor are controlled through a contact of the ice point protector, and the contact is closed through the power-on delay of a time relay, so that the compressor is ensured to be started again for more than 3 min. The problem that the normal operation of a unit is influenced because the evaporator is frosted and frozen until the compressor is damaged by liquid impact when the high-temperature air-conditioning refrigeration system continues to refrigerate when the ambient temperature is lower is effectively solved.
3. The invention has simple structure, low failure rate, safety, reliability and low cost, thereby having strong economical efficiency and practicability.
4. The invention improves the adaptability of the refrigerating system with large temperature change and large load change by the optimized matching and effective control measures of the refrigerating system.
Drawings
FIG. 1 is a block diagram of the system of the present invention.
Fig. 2 is a schematic diagram of the electrical portion of the present invention.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
As shown in fig. 1, the freezing prevention control system for the high-temperature air conditioner is used for a closed circulation refrigeration loop consisting of a compressor 1, an evaporator 3 with an evaporation fan 2, an expansion valve 4, a filter 5, an accumulator 6 and a condenser 7 with a condensation fan 9. In the closed circulation refrigeration system, the exhaust end of a compressor 1 is connected with the inlet end of a condenser 7 through a copper pipe, the outlet end of the condenser 7 is communicated with the interior of a liquid storage device 6 through a copper pipe, the interior of the liquid storage device 6 is also connected with the inlet end of a filter 5 through a copper pipe, the outlet end of the filter 5 is connected with the inlet end of an expansion valve 4 through a copper pipe, the outlet end of the expansion valve 4 is connected with the inlet end of an evaporator 3 through a copper pipe, the outlet end of the evaporator 3 is connected with the air return end of the compressor 1 through a copper pipe, a closed circulation refrigeration loop is formed, and R134.
The control system comprises an alternating current contactor KM 12 of a compressor 1, a time relay KT 13, an ice point protector ST8, a high-pressure controller 11 and a low-pressure controller 10. A temperature sensing copper sleeve is welded on the coil pipe of the evaporator 3, and a temperature sensing probe of a freezing point protector ST8 is inserted into the temperature sensing copper sleeve; the low pressure controller 10 is inserted in the copper pipe at the return end of the compressor 1, and the high pressure controller 11 is inserted in the copper pipe at the exhaust end of the compressor 1 and welded into the system by a brazing bar with 15% silver content.
A contact 11-1 of a high-pressure controller 11, a contact 10-1 of a low-pressure controller 10, a power-on delay closing contact KT-1 of a time relay KT 13 and a coil KM-1 of an alternating current contactor KM 12 of a compressor 1 are sequentially connected in series to form a first series branch, two ends of the first series branch are respectively connected with a live wire L and a zero wire N of a power supply, a contact ST-1 of a freezing point protector ST8 and a coil KT-2 of the time relay KT 13 are connected in series to form a second series branch, and the second series branch is connected in parallel to a series part of the power-on delay closing contact KT-1 of the time relay KT 13 and the coil KM-1 of the alternating current contactor KM 12 of.
The invention relates to a condenser 7, wherein the outlet of the condenser is provided with a liquid storage device 6, when the heat load is reduced or the environment temperature is lower, the refrigerant can not be completely evaporated in the evaporator 3, which can cause the surplus of the refrigerant of the air-conditioning refrigeration system at low temperature, thus the refrigerant liquid and the refrigerant gas can be mixed and enter the compressor 1, therefore, the liquid storage device 6 is arranged before entering the evaporator 3 to store the liquid refrigerant, and the liquid refrigerant is prevented from entering the suction cavity of the compressor 1 to break down the suction valve plate, namely 'liquid impact', to cause the damage of the compressor 1. Therefore, the liquid storage device 6 is additionally arranged in the refrigerating system, so that certain refrigerant can be stored when the refrigerating working condition is changed violently, and the system pressure is stabilized. Thus, the provision of the accumulator 6 may improve the flexibility of the refrigeration system for systems with wide temperature variations and load variations.
A temperature sensing copper sleeve is welded on a coil of the evaporator 3, a temperature sensing probe of the freezing point protector ST8 is inserted to sense the temperature of the evaporator coil, a proper action temperature value (set to be-2 ℃, the contact is disconnected, the return difference is 8 ℃ and the contact is closed.) is set for the freezing point protector, the start and stop of the compressor 1 are controlled through the contact ST-1 of the freezing point protector ST8, the contact KT-1 is closed through the power-on delay of the time relay KT 13, the alternating current contactor KM 12 of the compressor 1 is controlled, and the compressor 1 is ensured to be started again for more than 3 min. When the temperature sensing probe of the freezing point protector ST8 senses the temperature of the coil of the evaporator at minus 2 ℃, the contact ST-1 of the freezing point protector ST8 is disconnected, the coil KT-2 of the time relay KT 13 loses power, the time relay KT 13 is electrified to delay the closing contact KT-1 to be disconnected instantly, the coil KM-1 of the alternating current contactor KM 12 of the compressor 1 loses power, the compressor 1 stops working, and frost (ice) on the coil of the evaporator 3 and on the fins is gradually dissolved. When the temperature of the coil pipe of the evaporator 3 is sensed to reach 6 ℃ by the temperature sensing probe of the freezing point protector ST8, the contact ST-1 of the freezing point protector ST8 is closed, the coil KM-1 of the time relay KT 13 is electrified, the electrified delay closing contact KT-1 of the time relay KT 13 is closed in a delay mode for 3min, the coil KM-1 of the alternating current contactor KM 12 of the compressor 1 is electrified, the compressor 1 is started, and the refrigerating system operates normally. Therefore, the temperature sensing probe of the freezing point protector ST8 senses the temperature of the evaporator coil to control the starting and stopping of the compressor 1, so that the normal defrosting of the system is ensured, and the damage to the compressor caused by liquid impact is avoided.
When the air conditioner works in a low-temperature environment, the pressure of the system can be reduced, or the refrigerant of the system leaks to damage the compressor 1, in order to prevent the pressure of the refrigeration system from being too low, the low-pressure controller 10 is arranged, and when the pressure of the system is lower than the set value of the low-pressure controller 10, the compressor 1 is stopped.
When the air conditioner works in a high-temperature severe environment, the pressure of the system can rise, in order to prevent the compressor 1 from being damaged due to overhigh pressure of the refrigerating system, the high-pressure controller 11 is arranged, and when the pressure of the system exceeds the set value of the high-pressure controller 11, the compressor 1 is stopped.
The above embodiments are not limited to the scope of the present invention, and all modifications or variations based on the basic idea of the present invention are included in the scope of the present invention.
The embodiments of the present invention are described only for the preferred embodiments of the present invention, and not for the limitation of the concept and scope of the present invention, and various modifications and improvements made to the technical solution of the present invention by those skilled in the art without departing from the design concept of the present invention shall fall into the protection scope of the present invention, and the technical content of the present invention which is claimed is fully set forth in the claims.

Claims (4)

1. The utility model provides a high temperature air conditioner prevents frostbite control system for the closed cycle refrigeration circuit that constitutes by compressor, condenser, reservoir, filter, expansion valve, evaporimeter which characterized in that: comprises a freezing point protector, a high-pressure controller, a low-pressure controller, an alternating current contactor of a compressor and a time relay, the temperature sensing probe of the freezing point protector is in contact with a coil of the evaporator to measure the temperature of the evaporator coil, the high-pressure controller is installed on a pipeline at the exhaust end of the compressor, the low-pressure controller is installed on a pipeline at the air return end of the compressor, a contact of the high-pressure controller, a contact of the low-pressure controller, a power-on delay closing contact of the time relay and an alternating current contactor coil of the compressor are sequentially connected in series to form a first series branch, the power-on delay closing contact of the time relay and the alternating current contactor coil of the compressor in the first series branch form a compressor control section, two ends of the first series branch are respectively connected with an external power supply, a coil of the time relay and a contact of the freezing point protector are connected in series to form a second series branch, and the second series.
2. The system of claim 1, wherein the control system comprises: the closed circulation refrigeration loop is formed by connecting the exhaust end of the compressor with the inlet end of the condenser through a pipeline, communicating the outlet end of the condenser with the interior of the liquid storage device through a pipeline, connecting the interior of the liquid storage device with the inlet end of the filter through a pipeline, connecting the outlet end of the filter with the inlet end of the expansion valve through a pipeline, connecting the outlet end of the expansion valve with the inlet end of the evaporator through a pipeline, and connecting the outlet end of the evaporator with the air return end of the compressor through a pipeline.
3. The system of claim 1, wherein the control system comprises: the closed cycle refrigeration loop is circulated with R134a high-temperature environment-friendly refrigerant.
4. The system of claim 1, wherein the control system comprises: the coil pipe of the evaporator is provided with a temperature sensing copper sleeve, the pipe wall of the temperature sensing copper sleeve is welded on the pipe wall of the coil pipe of the evaporator, and a temperature sensing probe of the freezing point protector is inserted into the temperature sensing copper sleeve from the pipe orifice of the temperature sensing copper sleeve.
CN201910967800.3A 2019-10-12 2019-10-12 Anti-freezing control system of high-temperature air conditioner Pending CN110749038A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910967800.3A CN110749038A (en) 2019-10-12 2019-10-12 Anti-freezing control system of high-temperature air conditioner

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910967800.3A CN110749038A (en) 2019-10-12 2019-10-12 Anti-freezing control system of high-temperature air conditioner

Publications (1)

Publication Number Publication Date
CN110749038A true CN110749038A (en) 2020-02-04

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CN201910967800.3A Pending CN110749038A (en) 2019-10-12 2019-10-12 Anti-freezing control system of high-temperature air conditioner

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111823824A (en) * 2020-08-13 2020-10-27 合肥天鹅制冷科技有限公司 Anti-freezing control system of vehicle-mounted air conditioner
CN112902512A (en) * 2021-02-07 2021-06-04 中国地质科学院水文地质环境地质研究所 Sleeve type condenser low-temperature constant-temperature system and using method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111823824A (en) * 2020-08-13 2020-10-27 合肥天鹅制冷科技有限公司 Anti-freezing control system of vehicle-mounted air conditioner
CN112902512A (en) * 2021-02-07 2021-06-04 中国地质科学院水文地质环境地质研究所 Sleeve type condenser low-temperature constant-temperature system and using method thereof
CN112902512B (en) * 2021-02-07 2022-09-23 中国地质科学院水文地质环境地质研究所 Sleeve type condenser low-temperature constant-temperature system and using method thereof

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