CN217402693U - Special type electric machine room air conditioner low temperature refrigeration operation system - Google Patents
Special type electric machine room air conditioner low temperature refrigeration operation system Download PDFInfo
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- CN217402693U CN217402693U CN202220919967.XU CN202220919967U CN217402693U CN 217402693 U CN217402693 U CN 217402693U CN 202220919967 U CN202220919967 U CN 202220919967U CN 217402693 U CN217402693 U CN 217402693U
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Abstract
The utility model discloses a special electric machine room air conditioner low-temperature refrigeration operation system, which comprises a compressor, an evaporation fan, an evaporator, an expansion valve, a filter, a liquid storage device, a condenser and a condensation fan, wherein a pipeline is led out from the outlet of the liquid storage device, and is connected with the inlet of the liquid storage device after being connected with the filter, the expansion valve, the evaporator, the compressor and the condenser in sequence to form a closed refrigeration system; a high-precision pressure sensor is arranged in a connecting pipeline between the liquid storage device and the condenser, a low-pressure switch is arranged in an air return pipe of the compressor, and a crank heating belt is wound on the compressor and the liquid storage device. The utility model discloses take at reservoir of air conditioner refrigerating system condenser export installation, can guarantee when the refrigeration operating mode takes place the violent change, save certain refrigerant to stable system pressure. Therefore, the arrangement of the liquid storage device can improve the adaptability of the refrigerating system for the system with wide temperature change and load change.
Description
Technical Field
The utility model relates to an air conditioner refrigerating system and control technical field especially relate to a special type electrical equipment room air conditioner low temperature refrigeration operation system.
Background
The equipment machine rooms of equipment such as vehicles, aircrafts and the like for executing tasks such as transportation, communication, detection and the like, industrial equipment, power plants, oil drilling platforms and the like usually work in high-temperature environments, and special electric machine room air conditioners which are suitable for the working environments need to be matched for controlling the temperature of the equipment machine rooms. And some machine rooms, electronic cabins of carrying equipment, laser devices and the like operate all weather, when the environmental temperature (generally below 18 ℃) is low, the heat productivity of electrical components in the cooled machine cabinet is large, and air-conditioning refrigeration is still needed to cool the machine rooms and the cabins. When a conventional air conditioner product works at normal temperature, the 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, and even the liquid impact damage of the compressor can be caused, so that the normal use of a unit is influenced.
The high-temperature environment-friendly R134a refrigerant is adopted to ensure the high-temperature reliable operation of the refrigeration system; when the system operates at low temperature for refrigeration, in order to ensure the reliability of the system and the stability of the environment in the cabinet, the condensing pressure of the refrigeration system needs to be smoothly adjusted, a high-precision pressure sensor is arranged between a condenser and a liquid storage device, a pressure signal is converted into a 0-30V analog voltage signal by detecting the pressure value of the system, a lead is connected into a signal input interface of a controller, the signal input interface is logically judged by a CPU chip of the controller, a 0-10V PWM signal is output, a condensing speed regulating fan is controlled, the rotating speed of the fan is matched with the refrigeration system, the rotating speed of the condensing fan is smoothly changed within the curve range of the fan, and the condensing pressure of the system is stably adjusted.
Therefore, the air conditioner of the special electric machine room can reliably work at high temperature and low temperature under refrigeration condition, the working temperature zone is wide, and a proper system and a control measure suitable for the system are required to be configured to ensure the reliability of the refrigeration system.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the purpose is exactly in order to remedy prior art's defect, a special type electrical machine room air conditioner low temperature refrigeration operation system is provided, take a reservoir of export installation at air conditioner refrigerating system condenser, when the thermal load reduces or ambient temperature is lower, the refrigerant can not evaporate completely in the evaporimeter, can cause air conditioner refrigerating system refrigerant unnecessary when low temperature, just so can have refrigerant liquid and refrigerant gas mixture to get into the compressor, so will be advancing an evaporimeter front-end installation reservoir, store liquid refrigerant, prevent that liquid refrigerant from getting into the compressor chamber of breathing in, puncture the valve block of breathing in, promptly "liquid hits", cause the compressor to damage. Therefore, the liquid storage device 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. Therefore, the arrangement of the liquid storage device can improve the adaptability of the refrigerating system for a wide range of temperature change and load change systems.
The utility model discloses a realize through following technical scheme:
a low-temperature refrigeration operation system of a special electric machine room air conditioner comprises a compressor, an evaporator, an expansion valve, a filter, a liquid storage device, a condenser, an evaporation fan arranged on the evaporator and a condensation fan arranged on the condenser, wherein a pipeline is led out from an outlet of the liquid storage device, is connected with the filter, the expansion valve, the evaporator, the compressor and the condenser in sequence and then is connected with an inlet of the liquid storage device to form a closed refrigeration system; the condenser comprises a liquid storage device, a condenser and a controller, wherein a connecting pipeline between the liquid storage device and the condenser is provided with a pressure sensor, a muffler of the compressor is provided with a low-pressure switch, the pressure sensor and the low-pressure switch are respectively connected into a signal input interface I and a signal input interface II of the controller, and the compressor, an evaporation fan and a condensation fan are all electrically connected with the controller.
The liquid storage device, the filter, the expansion valve, the evaporator, the compressor and the condenser are sequentially connected through copper pipes.
The condensing fan is a PWM speed-regulating fan, and a PWM speed-regulating interface of the condensing fan is connected with the output end of the controller.
The compressor, the evaporation fan and the condensation fan are respectively connected with a compressor relay module, an evaporation fan relay module and a condensation fan relay module of the controller.
The compressor and the liquid storage tank are respectively wound with a compressor crank heating belt and a liquid storage tank crank heating belt, and the compressor crank heating belt and the liquid storage tank crank heating belt are respectively connected with a compressor crank heating belt relay module and a liquid storage tank crank heating belt relay module of the controller.
The controller also comprises an ambient temperature sensor, and the ambient temperature sensor is connected with the signal input interface III of the controller.
When the system operates in low-temperature refrigeration, a high-precision pressure sensor is arranged between a condenser and a liquid storage device in a refrigeration system, a pressure signal is converted into a 0-30V analog voltage signal by detecting a system pressure value, the analog voltage signal is connected to a signal input interface of a controller through a lead, the logic judgment is carried out by a CPU chip of the controller, a 0-10V PWM signal is output, a condensation speed regulating fan is controlled, the rotating speed of the condensation speed regulating fan is matched with that of the refrigeration system, the rotating speed of the condensation fan is smoothly changed within the curve range of the fan, and therefore the condensation pressure of the system is stably regulated.
The controller detects the state of a low-pressure switch arranged on a muffler of the compressor before starting up so as to solve the problem that the system cannot be started when the low-pressure switch is in a disconnected state when the ambient temperature is too low. The crank heating belt wound on the compressor and the liquid storage device shell under the low-temperature environment is controlled by detecting the outdoor environment temperature through the sensor, and the compressor and the liquid storage device are preheated before the compressor is started at low temperature.
The pressure sensor samples, converts a pressure signal into a 0-30V analog voltage signal, is connected into a controller signal input interface through a lead, is logically judged by a controller CPU chip, outputs a 0-10V PWM signal, and controls a condensation speed regulation fan, so that the problems that when the ambient temperature is too low, the condensation pressure of a system is too low, an expansion valve cannot obtain enough pressure drop at two ends of the expansion valve, an evaporator cannot obtain a proper amount of refrigerant, the refrigeration system cannot reach the hard requirement of refrigerating capacity, and frequent low-pressure alarm faults of the refrigeration system can be caused, the evaporator is frosted and frozen in severe cases, even a compressor is damaged by liquid impact, and the normal use of a unit is influenced are solved.
The low-pressure switch detects the state before starting up through the controller, so that the problem that the system cannot be started when the environment temperature is too low and the low-pressure switch is in a disconnected state is solved.
The compressor and the reservoir are preheated, and the start and stop of crank heating belts on the compressor and the reservoir shell are controlled by detecting the outdoor environment temperature through the controller.
The low-temperature refrigeration operation system of the air conditioner of the special electric machine room is characterized in that: the liquid storage device, the filter, the expansion valve, the evaporator, the compressor and the condenser are sequentially connected through copper pipes.
The low-temperature refrigeration operation system of the air conditioner of the special electric machine room is characterized in that: the controller carries out logic judgment processing on the input signal of the whole system and outputs the signal through the switching value output module.
The outlet of the condenser of the system is provided with the liquid accumulator, when the heat load is reduced or the ambient temperature is lower, the refrigerant can not be completely evaporated in the evaporator, the refrigerant of the air-conditioning refrigeration system is redundant at low temperature, so that the refrigerant liquid and the refrigerant gas can be mixed and enter the compressor, the liquid accumulator is arranged before the evaporator to store the liquid refrigerant, and the liquid refrigerant is prevented from entering the suction cavity of the compressor to break down the suction valve plate, namely 'liquid impact', so that the compressor is damaged. Therefore, the liquid storage device 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. Therefore, the arrangement of the liquid storage device can improve the adaptability of the refrigerating system for the system with wide temperature change and load change.
A high-precision pressure sensor is arranged in a connecting pipeline between a condenser and a liquid storage device, the pressure control range is 0 bar-18 bar, when the condensing pressure of a system is lower than 10bar, the high-precision pressure sensor converts a pressure signal into a voltage signal, a controller CPU outputs a voltage signal of not more than 0.5V to a condensing speed-regulating fan, the condensing fan stops, the condensing pressure of the system rises back, when the detected pressure is 10 bar-18 bar, the voltage is converted according to a linear proportion, the CPU outputs control voltage smoothly, the rotating speed of the fan is regulated to be matched with a refrigerating system, when the condensing pressure of the system is higher than 18bar, the CPU outputs a 10V voltage signal, and the condensing fan runs at full speed. The condensing pressure of the system is detected by a high-precision pressure sensor, the condensing pressure is converted into a 0-30V analog voltage signal, the signal is logically judged by a CPU chip of the controller, a 0-10V PWM signal is output, a condensing speed regulating fan is controlled, and the rotating speed of the smooth regulating fan is matched with a refrigerating system, so that the condensing pressure of the system is stably regulated.
The low-pressure switch lead wire installed on the compressor muffler is connected with the low-pressure switch signal input interface on the controller, when the ambient temperature is too low, the low-pressure switch contact is in a disconnected state, and when the system is started, the system cannot be started. Therefore, through programming, the state of the low-pressure switch signal input interface is not detected within 45s before starting, the chip directly outputs a signal for starting the compressor, and the compressor is started. After 45s of compressor operation, the system pressure builds up. And (4) closing the contact of the low-pressure switch when the low-pressure comes, and after 45s, detecting the state of the signal input interface of the low-pressure switch by the chip, and performing protection control on the compressor according to a logic program.
The environment temperature sensor is connected with a sensor signal input interface on the controller, before starting, when the sensor detects that the outdoor environment temperature is lower than 12 ℃, the controller chip judges through logic, outputs and connects a crank heating belt wound on the compressor and the liquid storage device shell, and preheats the compressor and the liquid storage device, so that when the temperature is low, the compressor is easy to start, and the refrigerant in the liquid storage device can normally flow.
The utility model has the advantages that:
1. the utility model discloses a design reliable refrigerating system and take rather than the control measure who suits, guarantee special electrical machine room air conditioner low temperature refrigeration operating system's reliability.
2. The utility model discloses take and at reservoir of air conditioner refrigerating system condenser export installation, can guarantee when the refrigeration operating mode takes place violent change, save certain refrigerant to stable system pressure. Therefore, the arrangement of the liquid storage device can improve the adaptability of the refrigerating system for the system with wide temperature change and load change.
3. The utility model discloses a high accuracy pressure sensor, PWM speed governing condensation speed governing fan, high accuracy pressure sensor are transformed into 0~30V analog voltage signal with pressure signal, are judged by controller CPU chip logic, export 0~10V PWM signal, control condensation speed governing fan to when solving ambient temperature too low, system condensation pressure is low excessively, and the system can not normally work and refrigeration operational reliability problem.
4. The utility model discloses take before the start compressor start-up in 45s not detect the low pressure switch's of installation on the compressor muffler state, solved when ambient temperature is too low, low pressure switch is in off-state, the problem that the system can not start.
5. The utility model discloses a refrigerating system's optimization matches and effectual control measure, has improved refrigerating system's adaptability that temperature variation is big and load variation is big.
Drawings
Fig. 1 is a diagram of the condensing pressure adjusting device of the present invention.
Fig. 2 is a structural diagram of the present invention.
Fig. 3 is a control schematic diagram of the present invention.
Detailed Description
As shown in fig. 2, a low-temperature refrigeration operation system of a vehicle-mounted air conditioner comprises a compressor 1, an evaporation fan 2, an evaporator 3, an expansion valve 4, a filter 5, a liquid storage device 6, a condenser 7 and a condensation fan 9, wherein a pipeline is led out from an outlet of the liquid storage device 6, is connected with the filter 5, the expansion valve 4, the evaporator 3, the compressor 1 and the condenser 7 in sequence, and then is connected with an inlet of the liquid storage device 6 to form a closed refrigeration system; a pressure sensor 8 is arranged in a connecting pipeline between the liquid storage device 6 and the condenser 7, and a low-pressure switch 10 is arranged in an air return pipe of the compressor 1; a lead of the pressure sensor 8 is connected to a first signal input interface 22 of the controller 13, a lead of the low-voltage pressure switch 10 is connected to a second signal input interface 21 of the controller 13, and an ambient temperature sensor 24 is connected to a third signal input interface 23 of the controller 13; A0-10V PWM speed regulation interface of the condensation fan 9 is connected to a condensation fan speed regulation signal output interface 18 of the controller 13.
In the refrigerating system, a liquid storage 6, a filter 5, an expansion valve 4, an evaporator 3, a compressor 1 and a condenser 7 are connected in sequence through copper pipes.
The controller 13 performs logic judgment processing on the input signal of the whole system through the CPU chip 14, and outputs the signal through the compressor relay module 17, the evaporation fan relay module 16, the condensation fan relay module 15, the liquid reservoir crank heating belt relay module 19, and the compressor crank heating belt relay module 20.
The outlet of the condenser 7 of the system is provided with the liquid accumulator 6, when the heat load is reduced or the ambient temperature is lower, the refrigerant can not be completely evaporated in the evaporator 3, the refrigerant of the air-conditioning refrigeration system is redundant at low temperature, so that the refrigerant liquid and the refrigerant gas can be mixed and enter the compressor 1, the liquid accumulator 6 is arranged before 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', so that the compressor 1 is damaged. 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 high-precision pressure sensor 8 is arranged in a connecting pipeline between the condenser 7 and the liquid storage device 6, and the pressure control range is 0-18 bar, as shown in figure 1. When the condensing pressure of the system is lower than 10bar, the high-precision pressure sensor 8 converts the pressure signal into a voltage signal, a CPU chip 14 of a controller 13 outputs a voltage signal of not more than 0.5V, the condensing fan 9 stops through a condensing fan speed-regulating signal output interface 18 to a 0-10V PWM speed-regulating interface 9-1 of the condensing fan 9, then the condensing pressure of the system rises back, when the high-precision pressure sensor 8 detects that the condensing pressure of the system is 10 bar-18 bar, the voltage is converted according to the linear proportion of 10 bar-18 bar of a curve shown in figure 1, the CPU chip 14 smoothly outputs control voltage, the rotating speed of the condensing fan 9 is adjusted to be matched with the refrigerating system, when the condensing pressure of the high-precision pressure sensor 8 is higher than 18bar, the CPU chip 14 on the controller 13 outputs a 10V voltage signal, and the condensing fan 9 runs at full speed. Therefore, the condensation pressure of the system is detected by the high-precision pressure sensor, the logic judgment of the CPU chip of the controller is carried out, a 0-10V PWM signal is output, the condensation speed-regulating fan is controlled, the rotating speed of the fan is smoothly regulated to be matched with the refrigerating system, and therefore the condensation pressure of the system is stably regulated.
As shown in fig. 3, the low pressure switch 10 installed on the compressor return air pipe is connected with the second low pressure switch signal input interface 21 on the controller 13, when the ambient temperature is too low, the contact of the low pressure switch 10 will be in an off state, and when the system is started, the system will not be started. Therefore, through programming, the state of the second low-pressure switch signal input interface 21 is not detected within 45s before starting, the CPU chip 14 directly outputs a signal for starting the compressor 1, and the compressor 1 is started. After 45s of operation of the compressor 1, the system pressure builds up. When the low pressure comes, the contact of the low pressure switch 10 is closed, and after 45s, the CPU chip 14 starts to detect the state of the second low pressure switch signal input interface 21, and performs protection control on the compressor 1 according to the logic program.
The environment temperature sensor 24 is connected with the signal input interface III 23 on the controller 13, before starting, when the environment temperature sensor 24 detects that the outdoor environment temperature is lower than 12 ℃, the CPU chip 14 on the controller 13 judges through logic, and outputs through the liquid storage device crank heating belt relay module 19 and the compressor crank heating belt relay module 20, the compressor crank heating belt 12 and the liquid storage device crank heating belt 11 wound on the shell of the compressor 1 and the liquid storage device 6 are respectively connected, the compressor 1 and the liquid storage device 6 are preheated, so that when the temperature is low, the compressor is easy to start, and the refrigerant in the liquid storage device can normally flow.
The above embodiments are not limited to the protection scope of the present invention, and all modifications or changes based on the basic idea of the present invention belong to the protection scope of the present invention.
Claims (6)
1. The utility model provides a special type electrical machinery room air conditioner low temperature refrigeration operating system which characterized in that: the refrigeration system comprises a compressor, an evaporator, an expansion valve, a filter, a liquid storage device, a condenser, an evaporation fan arranged on the evaporator and a condensation fan arranged on the condenser, wherein a pipeline is led out from an outlet of the liquid storage device, is sequentially connected with the filter, the expansion valve, the evaporator, the compressor and the condenser and then is connected to an inlet of the liquid storage device to form a closed refrigeration system; the condenser comprises a liquid storage device, a condenser, a controller, a connecting pipeline, a pressure sensor, a low-pressure switch, a first signal input interface and a second signal input interface, wherein the connecting pipeline between the liquid storage device and the condenser is provided with the pressure sensor, the muffler of the compressor is provided with the low-pressure switch, the pressure sensor and the low-pressure switch lead are respectively connected into the first signal input interface and the second signal input interface of the controller, and the compressor, an evaporation fan and a condensation fan are all electrically connected with the controller.
2. The special type electric machine room air conditioner low-temperature refrigerating operation system as claimed in claim 1, wherein: the liquid storage device, the filter, the expansion valve, the evaporator, the compressor and the condenser are sequentially connected through copper pipes.
3. The special type electric machine room air conditioner low-temperature refrigerating operation system as claimed in claim 1, wherein: the condensation fan is a PWM speed regulation fan, and a PWM speed regulation interface of the condensation fan is connected with the output end of the controller.
4. The special type electric machine room air conditioner low-temperature refrigerating operation system as claimed in claim 1, wherein: the compressor, the evaporation fan and the condensation fan are respectively connected with a compressor relay module, an evaporation fan relay module and a condensation fan relay module of the controller.
5. The special electric machine room air conditioner low-temperature refrigerating operation system as claimed in claim 1, wherein: the compressor and the liquid storage tank are respectively wound with a compressor crank heating belt and a liquid storage tank crank heating belt, and the compressor crank heating belt and the liquid storage tank crank heating belt are respectively connected with a compressor crank heating belt relay module and a liquid storage tank crank heating belt relay module of the controller.
6. The special type electric machine room air conditioner low-temperature refrigerating operation system as claimed in claim 1, wherein: the controller also comprises an ambient temperature sensor, and the ambient temperature sensor is connected with the signal input interface III of the controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220919967.XU CN217402693U (en) | 2022-04-20 | 2022-04-20 | Special type electric machine room air conditioner low temperature refrigeration operation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220919967.XU CN217402693U (en) | 2022-04-20 | 2022-04-20 | Special type electric machine room air conditioner low temperature refrigeration operation system |
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| Publication Number | Publication Date |
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| CN217402693U true CN217402693U (en) | 2022-09-09 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202220919967.XU Active CN217402693U (en) | 2022-04-20 | 2022-04-20 | Special type electric machine room air conditioner low temperature refrigeration operation system |
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| CN (1) | CN217402693U (en) |
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- 2022-04-20 CN CN202220919967.XU patent/CN217402693U/en active Active
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