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CN-122018597-A - Linear cooling control method of environment test box and environment test box

CN122018597ACN 122018597 ACN122018597 ACN 122018597ACN-122018597-A

Abstract

The application discloses a linear cooling control method of an environment test box and the environment test box, wherein the method comprises the steps of determining the linear cooling rate of the environment test box to be controlled; the method comprises the steps of determining linear target temperature at any moment based on a linear cooling rate, obtaining current temperature parameters of an environment test box to be controlled, respectively calculating the opening of a main circuit electronic expansion valve, the opening of a liquid bypass electronic expansion valve and the rotating speed of an evaporator fan of the environment test box to be controlled based on the linear target temperature and the current temperature parameters, respectively controlling the main circuit electronic expansion valve, the liquid bypass electronic expansion valve and the rotating speed of the evaporator fan of the environment test box to be controlled based on the calculated opening of the main circuit electronic expansion valve, the opening of the liquid bypass electronic expansion valve and the rotating speed of the evaporator fan, and achieving the linear cooling control of the environment test box to be controlled. The application solves the technical problems of poor stability of a linear cooling temperature curve and poor system operation reliability in the linear cooling process of the existing environment test box.

Inventors

  • SHI JIANWEI

Assignees

  • 江苏拓米洛高端装备股份有限公司

Dates

Publication Date
20260512
Application Date
20240524

Claims (10)

  1. 1. The linear cooling control method for the environmental test chamber is characterized by comprising the following steps of: Determining the linear cooling rate of an environment test chamber to be controlled; determining a linear target temperature at any moment based on the linear cooling rate; acquiring current temperature parameters of the environment to be controlled test box, wherein the current temperature parameters comprise the temperature in the environment to be controlled test box, the inlet temperature of an evaporator, the outlet temperature of the evaporator, the inlet air temperature of the evaporator and the air suction temperature of a compressor; Calculating the opening of a main circuit electronic expansion valve, the opening of a liquid bypass electronic expansion valve and the rotating speed of an evaporator fan of the environment to be controlled test box based on the linear target temperature and the current temperature parameter respectively; Based on the calculated opening of the main electronic expansion valve, the opening of the liquid bypass electronic expansion valve and the rotating speed of the evaporator fan, the main electronic expansion valve, the liquid bypass electronic expansion valve and the evaporator fan of the environment test box to be controlled are respectively controlled to act, so that the linear cooling control of the environment test box to be controlled is realized; Calculating the rotation speed of the evaporator fan of the environment to be controlled test box based on the linear target temperature and the current temperature parameter comprises the following steps: based on the linear target temperature and the current temperature parameter, utilizing an evaporator fan rotating speed formula Calculating the rotation speed of the evaporator fan, wherein H is the rotation speed of the evaporator fan, K 3 、I 3 、D 3 is the proportional coefficient, integral coefficient and differential coefficient of proportional-integral-differential control of the rotation speed of the evaporator fan, H (tau) is the control deviation of the rotation speed of the evaporator fan, tau is any time within the total cooling time t, T ai is the evaporator inlet air temperature, T is the in-tank temperature, B s is a second target value in a second database, and s is the number of the linear target temperature.
  2. 2. The method of linear cooling control of an environmental chamber of claim 1, wherein determining a linear cooling rate of the environmental chamber to be controlled comprises: acquiring preset temperature parameters of the environment to be controlled test box, wherein the preset temperature parameters at least comprise one of initial temperature, final temperature and total cooling time; and determining the linear cooling rate of the environment to be controlled test box by using the preset temperature parameter.
  3. 3. The method for controlling linear cooling of an environmental chamber according to claim 2, wherein the initial temperature T0, the final temperature T SV , and the total cooling time T of the environmental chamber to be controlled are obtained, and then the formula is used And determining the linear cooling rate of the environment to be controlled test box, wherein V is the linear cooling rate.
  4. 4. The method of linear cooling control of an environmental chamber of claim 1, wherein determining a linear target temperature at any time based on the linear cooling rate comprises: And determining a linear target temperature at any time by using T n =T 0 -Vτ n based on the linear cooling rate, wherein T n is the linear target temperature, n is a number corresponding to the linear target temperature and any time tau, V is the linear cooling rate, and T 0 is the starting temperature.
  5. 5. The method of claim 4, wherein calculating the opening of the liquid bypass electronic expansion valve of the environmental test chamber to be controlled based on the current temperature parameter comprises: based on the linear target temperature and the current temperature parameter, utilizing a main circuit electronic expansion valve opening formula Calculating the opening of the main electronic expansion valve, wherein Z is the opening of the main electronic expansion valve, K 1 、I 1 、D 1 is the proportional coefficient, integral coefficient and differential coefficient of proportional-integral-differential control of the main electronic expansion valve, e (tau) is the main control deviation, tau is any time within the total cooling time t, T is the temperature in the box, T 0 is the initial temperature, T SV is the final temperature, p is the main gain coefficient, V is the linear cooling rate, V C is a rate constant, T C is a temperature constant, T n is the linear target temperature, and n is the number corresponding to the linear target temperature and the corresponding time.
  6. 6. The method for controlling the linear cooling of an environmental test chamber according to claim 1, wherein before calculating the opening degree of the liquid bypass electronic expansion valve of the environmental test chamber to be controlled based on the current temperature parameter, the method further comprises: And establishing a first database among the evaporation temperature of the environment to be controlled test box, the temperature in the box and a first target value, wherein the first target value is a target value of the difference between the suction temperature of the compressor and the outlet temperature of the evaporator.
  7. 7. The method of claim 6, wherein calculating the opening of the liquid bypass electronic expansion valve of the environmental test chamber to be controlled based on the current temperature parameter comprises: based on the current temperature parameter, utilizing a liquid bypass electronic expansion valve opening formula Calculating the opening of the liquid bypass electronic expansion valve, wherein Q is the opening of the liquid bypass electronic expansion valve, K 2 、I 2 、D 2 is the proportional coefficient, integral coefficient and differential coefficient of proportional-integral-differential control of the liquid bypass electronic expansion valve, Q (tau) is the liquid bypass control deviation, tau is any time within the total cooling time t, T a is the compressor suction temperature, T eo is the evaporator outlet temperature, A ij is the first target value in the first database, i is the number of evaporation temperatures, j is the number of temperatures in the tank, m is the liquid bypass gain factor, T is the temperature in the tank, and T Q is the temperature constant of the electronic expansion valve.
  8. 8. The method of controlling linear cooling of an environmental chamber according to claim 1, wherein after determining a linear target temperature at any time based on the linear cooling rate, the method further comprises: and establishing a second database among the linear target temperature, the linear cooling rate and a second target value, wherein the second target value is a target value of the difference between the evaporator air inlet temperature and the in-box temperature.
  9. 9. An environmental test chamber, characterized in that the environmental test chamber comprises a chamber body, a control system and a refrigerating system, wherein the control system executes the linear cooling control method of the environmental test chamber according to any one of the claims 1-8; the control system comprises a display unit, a sensor unit and a control unit, wherein the sensor unit is arranged in the box body, the display unit is arranged on the surface of the box body, the control unit is arranged in or outside the box body, and the display unit and the sensor unit are respectively and electrically connected with the control unit; the refrigerating system is arranged in the box body and comprises a compressor, a condenser, an evaporator fan, a main circuit electronic expansion valve and a liquid bypass electronic expansion valve; the main path electronic expansion valve, the evaporator, the compressor and the condenser are sequentially connected in series to form a loop, the liquid bypass electronic expansion valve is connected in parallel with the two ends of the evaporator and the main path electronic expansion valve, and the evaporator fan is arranged at the evaporator.
  10. 10. The environmental chamber of claim 9 wherein the sensor unit comprises an in-chamber temperature sensor, an evaporator inlet air temperature sensor, an evaporator outlet temperature sensor, a compressor suction temperature sensor; The evaporator inlet temperature sensor is arranged at the inlet of the evaporator, the evaporator outlet temperature sensor is arranged at the outlet of the evaporator, and the compressor suction temperature sensor is arranged at the air suction port of the compressor; The control unit comprises a liquid bypass electronic expansion valve control module, a main circuit electronic expansion valve control module and an acquisition calculation control module; the acquisition calculation control module is respectively and electrically connected with a sensor in the sensor unit, the liquid bypass electronic expansion valve control module and the main circuit electronic expansion valve; The liquid bypass electronic expansion valve control module is electrically connected with the liquid bypass electronic expansion valve; and the main electronic expansion valve control module is electrically connected with the main electronic expansion valve and the evaporator fan respectively.

Description

Linear cooling control method of environment test box and environment test box The application discloses a linear cooling control method of an environment test box and a divisional application of the environment test box, which are applied for 24 months of 2024 in 05 months, the application number 2024106563969 and the patent name. Technical Field The embodiment of the invention relates to the technical field of temperature control, in particular to a linear cooling control method of an environment test box and the environment test box. Background At present, a fixed-frequency compressor is mostly used for linear cooling, and the cooling capacity requirement in the early and middle stages of cooling is smaller than the capacity requirement of the compressor, so that the throttle valve adopts multi-branch combination and performs switch control in a temperature division interval. When the throttle valves of different branches are opened, the cooling capacity of the system is suddenly increased, so that the linear cooling temperature curve is greatly fluctuated, and at the moment, the system can adopt a heating countermeasure mode to reach curve stability again. When the throttle valve is opened, if the type selection or adjustment is unreasonable, the suction liquid of the compressor can be caused, and the reliability of the system is affected. Meanwhile, the control of the fan is also critical, when the air quantity of the fan is smaller, the refrigerant in the evaporator cannot be completely evaporated, and when the air quantity of the fan is larger, the energy conservation performance is poorer. In addition, in the earlier stage of cooling, because the initial temperature of cooling is higher, can lead to the compressor to breathe in higher temperature. To prevent overheating of the compressor motor, it is necessary to spray liquid to the compressor suction line, reducing the compressor suction line temperature. However, when the control accuracy of the liquid spraying amount is poor, the liquid is carried by the air suction of the compressor, and the operation reliability of the system is affected. Therefore, optimizing the system control and operation in the linear cooling process is important for the stability of the linear cooling temperature curve, the simplification of the system, the energy saving of the system and the reliability of the system operation. Disclosure of Invention The embodiment of the invention provides a linear cooling control method of an environment test box and the environment test box, which solve the technical problems of poor stability of a linear cooling temperature curve and poor system operation reliability in the linear cooling process of the existing environment test box. In a first aspect, an embodiment of the present invention provides a linear cooling control method for an environmental test chamber, where the control method includes: Determining the linear cooling rate of an environment test chamber to be controlled; determining a linear target temperature at any moment based on the linear cooling rate; acquiring current temperature parameters of the environment to be controlled test box, wherein the current temperature parameters comprise the temperature in the environment to be controlled test box, the inlet temperature of an evaporator, the outlet temperature of the evaporator, the inlet air temperature of the evaporator and the air suction temperature of a compressor; Calculating the opening of a main circuit electronic expansion valve, the opening of a liquid bypass electronic expansion valve and the rotating speed of an evaporator fan of the environment to be controlled test box based on the linear target temperature and the current temperature parameter respectively; Based on the calculated opening of the main electronic expansion valve, the opening of the liquid bypass electronic expansion valve and the rotating speed of the evaporator fan, the main electronic expansion valve, the liquid bypass electronic expansion valve and the evaporator fan of the environment test box to be controlled are respectively controlled to act, so that the linear cooling control of the environment test box to be controlled is realized; Calculating the rotation speed of the evaporator fan of the environment to be controlled test box based on the linear target temperature and the current temperature parameter comprises the following steps: based on the linear target temperature and the current temperature parameter, utilizing an evaporator fan rotating speed formula Calculating the rotation speed of the evaporator fan, wherein H is the rotation speed of the evaporator fan, K 3、I3、D3 is the proportional coefficient, integral coefficient and differential coefficient of proportional-integral-differential control of the rotation speed of the evaporator fan, H (tau) is the control deviation of the rotation speed of the evaporator fan, tau is any time within the total cooling time t,T ai