A method for rapid and stable temperature control of a refrigeration system compartment

Abstract

This invention discloses a method for rapid and stable temperature control of a refrigeration system compartment. The method includes: acquiring the current target temperature and the actual temperature of the temperature-controlled compartment; obtaining the current temperature deviation of the temperature-controlled compartment based on the current target temperature and the actual temperature; determining the current control mode of the electronic expansion valve of the temperature-controlled compartment based on the current temperature deviation and the preset temperature deviation; and adjusting the opening degree of the electronic expansion valve according to the current control mode. This method enables rapid and stable temperature regulation of the compartment, shortening the time for the compartment temperature to reach a stable state, allowing the equipment to quickly reach the testing state, improving user testing efficiency, and simultaneously reducing the output of the heater during temperature balancing, achieving energy-saving operation of the equipment.

Description

[0001] This application is a divisional application of patent application number 202310113627.7 (the original application was filed on February 15, 2023, and the invention was entitled "A Method for Rapid and Stable Control of Room Temperature in a Refrigeration System"). Technical Field

[0002] This invention relates to the field of testing equipment technology, and in particular to a method for rapid and stable temperature control of a compartment in a refrigeration system. Background Technology

[0003] An electronic expansion valve is a refrigerant flow regulating device driven by a stepper motor. This device controls the movement of the valve needle by providing a logic digital signal to the stepper motor, thereby controlling the valve's flow rate and area. In applications with drastic load changes, high temperature control accuracy, or a wide operating range, traditional throttling elements (such as capillary tubes and thermostatic expansion valves) can no longer meet the requirements for temperature control accuracy and energy saving; therefore, the application of electronic expansion valves is becoming increasingly widespread.

[0004] In the control of electronic expansion valves, a regulation strategy that focuses on the superheat at the evaporator outlet is widely adopted. This strategy regulates the refrigerant flow by controlling the deviation between the target and actual superheat values. Specifically, when the system load increases, the superheat deviation increases, causing the electronic expansion valve to open wider, thus increasing the refrigerant flow into the evaporator. Conversely, when the system load decreases, the superheat deviation decreases, causing the electronic expansion valve to open less, thus decreasing the refrigerant flow into the evaporator. This evaporator outlet superheat control strategy ensures that the refrigeration system operates close to its maximum cooling capacity at all times. This plays a crucial role in ensuring sufficient heat exchange in the refrigeration equipment's heat exchangers, accelerating system cooling, and preventing liquid carryover during compressor suction.

[0005] However, for the refrigeration system of environmental testing equipment, when the chamber temperature approaches the target temperature, especially under a relatively low heat load, if the refrigeration system continues to operate close to its maximum cooling capacity, the following drawbacks will occur: Firstly, it will cause a large overshoot in the chamber temperature, requiring multiple oscillations during the temperature equilibrium process, thus prolonging the time to reach a stable state and hindering the equipment from quickly reaching the testing state. Secondly, it will cause the heater output to be too high during the temperature equilibrium process, which is detrimental to the energy-saving operation of the equipment. Summary of the Invention

[0006] This invention provides a method for rapid and stable temperature control of a refrigeration system compartment, enabling the compartment temperature to quickly reach a stable state, shortening the time required for the compartment temperature to reach a stable state, allowing the equipment to quickly reach the test state, and improving user testing efficiency.

[0007] According to one aspect of the present invention, a method for rapidly stabilizing and controlling the temperature of a compartment in a refrigeration system is provided, the method comprising:

[0008] Obtain the current target temperature and the actual temperature of the temperature-controlled room;

[0009] The current temperature deviation of the temperature-controlled room is obtained based on the current target temperature and the actual temperature of the temperature-controlled room; wherein, the current temperature deviation of the temperature-controlled room is the current target temperature of the temperature-controlled room minus the actual temperature of the temperature-controlled room.

[0010] The current control mode of the electronic expansion valve in the temperature control chamber is determined based on the current temperature deviation and the preset temperature deviation, and the opening degree of the electronic expansion valve is adjusted according to the current control mode.

[0011] If the current temperature deviation of the temperature control chamber is greater than or equal to the preset temperature deviation, then the current control mode of the electronic expansion valve of the temperature control chamber is the target opening control mode.

[0012] The target opening control mode is as follows: determine the current bypass mode of the refrigeration system, and determine the target constant temperature pre-balance opening lookup table based on the current bypass mode and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table; obtain the current target temperature of the temperature-controlled chamber and the current external ambient temperature, and determine the target selection calculation block in the target constant temperature pre-balance opening lookup table based on the current target temperature of the temperature-controlled chamber and the current external ambient temperature; determine the current preset opening of the electronic expansion valve of the temperature-controlled chamber according to the preset target opening value calculation algorithm based on the target selection calculation block.

[0013] Optionally, the algorithm for calculating the preset target opening value is as follows:

[0014]

[0015] in,

[0016]

[0017]

[0018] Where x1 is the minimum boundary value of the target temperature in the temperature-controlled chamber of the target calculation block, x2 is the maximum boundary value of the target temperature in the temperature-controlled chamber of the target calculation block, y1 is the minimum boundary value of the external ambient temperature of the target calculation block, y2 is the maximum boundary value of the external ambient temperature of the target calculation block, and f(Q) 11 f(Q) 12 f(Q) 21 f(Q)22 The preset opening values ​​at the four vertices of the calculation block are selected for the target in turn.

[0019] Optionally, determining the target isostatic pre-balancing opening lookup table based on the current bypass mode and the correspondence between the preset bypass mode and the preset isostatic pre-balancing opening lookup table includes:

[0020] Determine the current bypass mode number based on the current bypass mode;

[0021] Based on the current bypass mode's mode number, query the correspondence between the preset bypass mode and the preset isothermal pre-balancing opening lookup table to determine the target isothermal pre-balancing opening lookup table.

[0022] Optionally, the target constant temperature pre-balance opening lookup table consists of multiple characteristic point values ​​of the target temperature of the temperature-controlled room, multiple characteristic point values ​​of the external ambient temperature, and multiple calculation blocks divided according to each characteristic point value.

[0023] The step of determining the target selection calculation block based on the current target temperature of the temperature-controlled room and the current external ambient temperature in the target constant temperature pre-equilibrium opening lookup table includes:

[0024] The target selection calculation block is determined based on the current target temperature of the temperature-controlled room, the current external ambient temperature, and the values ​​of each feature point.

[0025] Optionally, the refrigeration system includes at least a first hot gas bypass solenoid valve, a second hot gas bypass solenoid valve, and a cold gas bypass solenoid valve;

[0026] Determining the current bypass mode of the refrigeration system includes: determining the current bypass mode of the refrigeration system based on the on / off states of the first hot gas bypass solenoid valve, the second hot gas bypass solenoid valve, and the cold gas bypass solenoid valve.

[0027] Optionally, after adjusting the opening degree of the electronic expansion valve according to the current control mode, the method further includes:

[0028] Determine whether the current target temperature has changed, and if it has changed, return to execute the operation of obtaining the current temperature deviation of the temperature control room based on the current target temperature of the temperature control room and the actual temperature of the temperature control room until the current target temperature no longer changes.

[0029] Optionally, if the current temperature deviation of the temperature control chamber is less than the preset temperature deviation, the current control mode of the electronic expansion valve of the temperature control chamber is the superheat deviation control mode.

[0030] Optionally, the superheat deviation control mode is:

[0031] The system obtains the current superheat and target superheat of the evaporator; and performs PID control on the opening of the electronic expansion valve based on the deviation between the current superheat and target superheat of the evaporator.

[0032] Optionally, the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table is a one-to-one correspondence.

[0033] Optionally, the bypass mode number is determined based on the number of all bypass modes in the refrigeration system, and each bypass mode corresponding to a mode number is provided with a constant temperature pre-balance opening lookup table.

[0034] The technical solution of this invention provides a method for rapid and stable temperature control of a refrigeration system compartment. This method includes: acquiring the current target temperature and the actual temperature of the temperature-controlled compartment; obtaining the current temperature deviation of the temperature-controlled compartment based on the current target temperature and the actual temperature; determining the current control mode of the electronic expansion valve of the temperature-controlled compartment based on the current temperature deviation and a preset temperature deviation; and adjusting the opening degree of the electronic expansion valve according to the current control mode. This method enables the following: by acquiring the current target temperature and the actual temperature of the temperature-controlled chamber in real time, and obtaining the current temperature deviation of the temperature-controlled chamber based on these two temperatures, the current control mode of the electronic expansion valve of the temperature-controlled chamber can be reasonably determined based on the current temperature deviation and the preset temperature deviation. Finally, the opening degree of the electronic expansion valve of the temperature-controlled chamber is controlled according to the obtained control mode to achieve rapid and stable temperature regulation of the chamber, shorten the time for the chamber temperature to reach a stable state, enable the equipment to quickly reach the test state, improve user testing efficiency, and at the same time reduce the output of the heater during the temperature balancing process, thereby achieving energy-saving operation of the equipment.

[0035] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram illustrating the extended time required for the intermediate chamber temperature to reach a stable state in existing technologies.

[0038] Figure 2 This is a schematic diagram showing that the heater output is too large during the temperature balancing process in the intermediate chamber of existing technology.

[0039] Figure 3 This is a flowchart of a method for rapidly stabilizing the temperature of a compartment in a refrigeration system, provided in an embodiment of the present invention.

[0040] Figure 4 This is a flowchart of another method for rapidly stabilizing the temperature of a refrigeration system compartment, provided in an embodiment of the present invention.

[0041] Figure 5 This is a flowchart of a control method for a target opening control mode of an electronic expansion valve provided in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the principle structure of a refrigeration system provided in an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram showing the distribution of various bypass modes of the refrigeration system provided in the embodiments of the present invention;

[0044] Figure 8 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 1 provided in this embodiment of the invention;

[0045] Figure 9 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to the bypass mode 2 provided in this embodiment of the invention;

[0046] Figure 10 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 3 provided in this embodiment of the invention;

[0047] Figure 11 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 4 provided in this embodiment of the invention;

[0048] Figure 12 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 5 provided in this embodiment of the invention;

[0049] Figure 13 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 6 provided in this embodiment of the invention;

[0050] Figure 14 This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to the bypass mode 7 provided in this embodiment of the invention;

[0051] Figure 15This is a schematic diagram of the structure of the constant temperature pre-balance opening lookup table corresponding to bypass mode 8 provided in this embodiment of the invention;

[0052] Figure 16 This is a flowchart of a control method for another electronic expansion valve target opening control mode provided in an embodiment of the present invention;

[0053] Figure 17 This is a block division diagram of a constant temperature pre-balance opening lookup table provided in an embodiment of the present invention;

[0054] Figure 18 This is a schematic diagram of bilinear interpolation provided in an embodiment of the present invention. Detailed Implementation

[0055] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0056] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0057] Figure 1 This is a schematic diagram illustrating the extended time required for the intermediate chamber temperature to reach a stable state in existing technologies. Figure 2 This diagram illustrates the excessive heater output during the temperature balancing process in the intermediate chamber of existing technology. The inventors discovered that the electronic expansion valve is a refrigerant flow regulating device driven by a stepper motor. This device controls the movement of the valve needle by providing a logic digital signal to the stepper motor, thereby controlling the valve flow and area. In applications with drastic load changes, high temperature control accuracy, or a wide operating range, traditional throttling elements (such as capillary tubes and thermostatic expansion valves) can no longer meet the requirements for temperature control accuracy and energy saving; therefore, the application of electronic expansion valves is becoming increasingly widespread.

[0058] In the control of electronic expansion valves, a large number of adjustment strategies are adopted with the superheat of the evaporator outlet as the control object. This strategy adjusts the refrigerant flow by controlling the deviation between the target value and the actual value of the superheat. For example, CN103743063 B discloses a control method for electronic expansion valves during air conditioning cooling, which is used to control the opening degree of electronic expansion valves in air conditioning systems. The air conditioning system includes a compressor, evaporator, condenser, electronic expansion valve and control system. Temperature sensors are respectively provided in the middle of the evaporator, the evaporator outlet and the middle of the condenser. Each temperature sensor is connected to the control system, and the electronic expansion valve adjusts its opening degree under the control of the control system. The opening degree control method includes: the electronic expansion valve opening degree initialization is completed and held for time t, and then the temperature Tc in the middle of the condenser is detected; (1) when Tc < T1, the electronic expansion valve is set to the minimum opening degree; (2) when Tc > Th, the electronic expansion valve is set to the maximum opening degree; (3) when T1 ≤ Tc ≤ Th, the temperature Tm in the middle of the evaporator and the temperature Tg at the evaporator outlet are detected, and the evaporator temperature is obtained. The outlet superheat ΔT = Tg - Tm; the target superheat Tsh at the evaporator outlet is set based on the detected condenser mid-temperature Tc, where Tsh = [a - (Tc - 45) * b] * Tsh0; when ΔT - Tsh > 1℃, the opening of the electronic expansion valve is increased; when -1℃ < ΔT - Tsh ≤ 1℃, the existing opening of the electronic expansion valve is maintained; when ΔT - Tsh ≤ -1℃, the opening of the electronic expansion valve is decreased; where T1 is the saturation temperature corresponding to the minimum allowable discharge pressure of the compressor, and Th is the saturation temperature corresponding to the maximum allowable discharge pressure of the compressor; a and b are correction parameters obtained through curve fitting; Tsh0 is the basic parameter of evaporator outlet superheat obtained by adjusting the opening of the electronic expansion valve to bring the refrigeration system to its optimal operating state under the standard refrigeration test conditions.

[0059] To improve the reliability of the regulation strategy that uses the evaporator outlet superheat as the control object, CN 112303972 B discloses an electronic expansion valve control method, system, and refrigeration system. The method includes: real-time detection of evaporator superheat Δ; PID regulation of the opening of the electronic expansion valve based on the difference between the evaporator superheat Δ and a set target evaporator superheat Δ; when the evaporator superheat Δ is greater than the set liquid-carrying protection superheat Δ, the regulation coefficient of the PID regulation is set to: proportional coefficient Kp, integral time constant Ti, and derivative time constant Td; otherwise, the regulation coefficient of the PID regulation is set to: proportional coefficient Kp, anti-liquid-carrying integral time constant Ti, and derivative time constant Td.

[0060] The regulation strategy, which uses the evaporator outlet superheat as the control object, regulates the refrigerant flow by controlling the deviation between the target and actual superheat values. Specifically, when the system load increases, the superheat deviation increases, leading to a larger opening of the electronic expansion valve and thus an increase in the refrigerant flow into the evaporator; conversely, when the system load decreases, the superheat deviation decreases, leading to a smaller opening of the electronic expansion valve and a smaller refrigerant flow into the evaporator. This evaporator outlet superheat control strategy ensures that the refrigeration system operates close to its maximum cooling capacity at all times. This is crucial for ensuring sufficient heat exchange in the refrigeration equipment's heat exchangers, accelerating system cooling, and preventing liquid carryover during compressor suction. However, for refrigeration systems in environmental testing equipment, when the chamber temperature Tipv approaches the target temperature Tisv, especially under lower heat loads, if the refrigeration system continues to operate close to its maximum cooling capacity, the following shortcomings arise: Firstly, such as... Figure 1 As shown, this results in a large overshoot in the chamber temperature Tipv. The Tipv temperature equilibrium process requires multiple oscillations, thus prolonging the time to reach a steady state, which is detrimental to the equipment's ability to quickly reach the test state. On the other hand, as... Figure 2 As shown, this results in an excessively high heater output of heater HT during the temperature equilibrium process, which is detrimental to the energy-saving operation of the equipment.

[0061] Therefore, embodiments of the present invention provide a method for rapid and stable temperature control of a refrigeration system compartment, so as to enable the compartment temperature to quickly reach a stable state, shorten the time for the compartment temperature to reach a stable state, enable the equipment to quickly reach the test state, and improve the user's testing efficiency.

[0062] Figure 3 This is a flowchart illustrating a method for rapidly stabilizing the temperature of a compartment in a refrigeration system, as provided in an embodiment of the present invention. (Reference) Figure 3 The method includes:

[0063] S110: Obtain the current target temperature and the actual temperature of the temperature-controlled room.

[0064] The current target temperature of the temperature-controlled room can be obtained through the temperature settings or management platform of the temperature-controlled room. The actual temperature of the temperature-controlled room can be obtained through temperature sensors.

[0065] S120. Obtain the current temperature deviation of the temperature control room based on the current target temperature and the actual temperature of the temperature control room.

[0066] Let Tipv_err be the current temperature deviation of the temperature-controlled room. Then Tipv_err is:

[0067] Tipv_err = Tisv - Tipv

[0068] Where Tisv is the current target temperature of the temperature-controlled room, and Tipv is the actual temperature of the temperature-controlled room.

[0069] S130. Determine the current control mode of the electronic expansion valve of the temperature control chamber based on the current temperature deviation and the preset temperature deviation, and adjust the opening degree of the electronic expansion valve according to the current control mode.

[0070] The specific value of the preset temperature deviation can be set according to the actual situation, and no specific limit is set here.

[0071] In the technical solution of this embodiment, the working principle of the rapid and stable temperature control method for the refrigeration system compartment is as follows: (Refer to...) Figure 3 First, the current target temperature and actual temperature of the temperature-controlled chamber are acquired. Then, the current temperature deviation of the temperature-controlled chamber is calculated based on these two values. Finally, the current control mode of the electronic expansion valve in the temperature-controlled chamber is determined based on the current temperature deviation and the preset temperature deviation, and the valve opening is adjusted accordingly. This method achieves rapid and stable temperature regulation of the chamber by acquiring the current target temperature and actual temperature in real time, calculating the current temperature deviation, determining the appropriate control mode for the electronic expansion valve based on this deviation and the preset temperature deviation, and finally controlling the valve opening according to the obtained mode. This results in rapid and stable temperature adjustment of the chamber, shortening the time it takes for the temperature to stabilize, enabling the equipment to quickly reach the testing state, improving user testing efficiency, and reducing heater output during temperature balancing, thus achieving energy-saving operation of the equipment.

[0072] Figure 4 This is a flowchart of another method for rapidly stabilizing and controlling the temperature of a refrigeration system compartment, provided in an embodiment of the present invention. Optionally, based on the above embodiments, refer to... Figure 4 The method includes:

[0073] S210: Obtain the current target temperature and the actual temperature of the temperature-controlled room.

[0074] S220. The current temperature deviation of the temperature control room is obtained based on the current target temperature and the actual temperature of the temperature control room.

[0075] S230. Determine whether the current temperature deviation of the temperature control room is less than the preset temperature deviation; if yes, proceed to step S240; otherwise, proceed to step S250.

[0076] The electronic expansion valve offers two opening control modes: superheat deviation control and target opening control. By comparing the current temperature deviation of the controlled chamber with the preset temperature deviation, the electronic expansion valve's opening control mode can be automatically and rationally switched, resulting in more reasonable opening control and enabling rapid and stable temperature control of the controlled chamber.

[0077] Specifically, if the current temperature deviation of the temperature-controlled chamber is less than the preset temperature deviation, step S240 is executed, meaning the opening control mode of the electronic expansion valve of the temperature-controlled chamber is set to superheat deviation control mode. Under this control mode, the equipment maintains a good cooling rate performance. If the current temperature deviation of the temperature-controlled chamber is greater than or equal to the preset temperature deviation, step S250 is executed, meaning the opening control mode of the electronic expansion valve of the temperature-controlled chamber is set to target opening control mode. This mode enables rapid temperature control of the chamber, shortening the time to reach a stable state, allowing the equipment to quickly reach the testing state, improving user testing efficiency. Simultaneously, the heater output is reduced during temperature balancing, enabling energy-saving operation of the equipment. Therefore, by comparing the current temperature deviation of the temperature-controlled chamber with the preset temperature deviation, the opening control mode of the electronic expansion valve of the temperature-controlled chamber is automatically and reasonably configured, achieving rapid and stable temperature control of the chamber.

[0078] The current control mode of the electronic expansion valve in the temperature control compartment of S240 is the superheat deviation control mode.

[0079] Specifically, if the current temperature deviation of the temperature control chamber is less than the preset temperature deviation, then step S240 is executed, that is, the opening control mode of the electronic expansion valve of the temperature control chamber is the superheat deviation control mode. Under this control mode, the equipment can maintain a better cooling rate performance.

[0080] Optionally, the superheat deviation control mode is as follows: obtain the current superheat and target superheat of the evaporator; and perform PID adjustment on the opening of the electronic expansion valve according to the deviation between the current superheat and target superheat of the evaporator.

[0081] The current control mode of the S250 temperature control compartment electronic expansion valve is the target opening control mode.

[0082] Specifically, if the current temperature deviation of the temperature control chamber is greater than or equal to the preset temperature deviation, then step S250 is executed, that is, the opening control mode of the electronic expansion valve of the control chamber is set to the target opening control mode. Through the control of this mode, the temperature of the chamber can be quickly controlled, the time to enter the stable state can be shortened, and the equipment can quickly reach the test state, improving the user's test efficiency. At the same time, the heater output is reduced during the temperature balancing process, which can realize energy-saving operation of the equipment.

[0083] S260. Determine whether the current target temperature has changed. If it has changed, return to the operation of step S220; otherwise, the program ends.

[0084] The process includes, after determining the current control mode for the opening of the electronic expansion valve and adjusting the opening of the electronic expansion valve according to the current control mode, further determining whether the current target temperature has changed. If it has changed, the process returns to step S220, redetermines the current temperature deviation of the temperature control chamber based on the current target temperature and the actual temperature of the temperature control chamber, and redetermines the opening control mode of the electronic expansion valve of the temperature control chamber by re-comparing the current temperature deviation of the temperature control chamber with the preset temperature deviation. This allows the opening control mode of the electronic expansion valve to be automatically adjusted according to the actual target temperature changes, thereby achieving accurate and reasonable control of the chamber temperature.

[0085] Specifically, it determines whether the current target temperature has changed, and if it has changed, it returns to the operation of obtaining the current temperature deviation of the temperature control room based on the current target temperature and the actual temperature of the temperature control room until the current target temperature no longer changes.

[0086] In the technical solution of this embodiment, the working principle of the rapid and stable temperature control method for the refrigeration system compartment is as follows: (Refer to...) Figure 4First, the current target temperature and the actual temperature of the temperature-controlled chamber are obtained. Then, the current temperature deviation of the temperature-controlled chamber is calculated based on these two temperatures. Next, it is determined whether the current temperature deviation is less than the preset temperature deviation. If so, the current control mode of the electronic expansion valve in the temperature-controlled chamber is set to superheat deviation control mode. Otherwise, the current control mode is set to target opening control mode. Finally, the opening of the electronic expansion valve is adjusted according to the current control mode. Furthermore, after adjusting the opening of the electronic expansion valve according to the current control mode, it is further determined whether the current target temperature has changed. If a change occurs, the process returns to calculating the current temperature deviation based on the current target temperature and the actual temperature of the temperature-controlled chamber until the current target temperature no longer changes. This method enables the following: by acquiring the current target temperature and the actual temperature of the temperature-controlled chamber in real time, and obtaining the current temperature deviation of the temperature-controlled chamber based on these two temperatures, the current temperature deviation can be accurately and reasonably determined by comparing it with the preset temperature deviation. Finally, the opening of the electronic expansion valve of the temperature-controlled chamber is controlled according to the obtained control mode to achieve rapid and stable temperature regulation of the chamber, shortening the time for the chamber temperature to reach a stable state, enabling the equipment to quickly reach the testing state, improving user testing efficiency, and reducing the output of the heater during the temperature balancing process, thus achieving energy-saving operation of the equipment.

[0087] Figure 5 This is a flowchart of a control method for a target opening control mode of an electronic expansion valve provided in an embodiment of the present invention. Optionally, refer to... Figure 5 The method includes:

[0088] S251. Determine the current bypass mode of the refrigeration system, and based on the current bypass mode and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table, determine the target constant temperature pre-balance opening lookup table.

[0089] There are various bypass modes in refrigeration systems, which are related to the type and number of bypass solenoid valves (including hot gas bypass solenoid valves and / or cold gas bypass solenoid valves) in the refrigeration system.

[0090] The correspondence between the preset bypass mode and the preset isothermal pre-balancing opening lookup table is one-to-one; that is, each bypass mode corresponds to a specific isothermal pre-balancing opening lookup table. Therefore, after determining the current bypass mode of the refrigeration system, the current isothermal pre-balancing opening lookup table can be determined based on the correspondence between the preset bypass mode and the preset isothermal pre-balancing opening lookup table.

[0091] S252. Obtain the current target temperature and current external ambient temperature of the temperature control chamber, and determine the current preset opening of the electronic expansion valve of the temperature control chamber based on the current target temperature of the temperature control chamber, the current external ambient temperature, and the target constant temperature pre-balance opening lookup table.

[0092] Specifically, when it is determined that the current temperature deviation of the temperature-controlled chamber is less than the preset temperature deviation, the electronic expansion valve is set to a reasonable preset opening degree when the refrigeration system reaches a constant temperature stable state under the current operating condition (i.e., the current bypass mode, the current target temperature of the temperature-controlled chamber, and the current external ambient temperature). This can achieve the pre-adjustment and release of refrigeration capacity, thereby better suppressing the temperature overshoot of the temperature-controlled chamber, reducing the number of oscillations, shortening the time to enter a constant temperature state, and achieving rapid and stable temperature control of the chamber.

[0093] The implementation principle of the target opening control mode of the electronic expansion valve provided in this embodiment is as follows: First, determine the current bypass mode of the refrigeration system, and determine the target constant temperature pre-balance opening lookup table based on the current bypass mode and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table. Then, obtain the current target temperature of the temperature control chamber and the current external ambient temperature, and determine the current preset opening of the electronic expansion valve in the temperature control chamber based on the current target temperature of the temperature control chamber, the current external ambient temperature, and the target constant temperature pre-balance opening lookup table. Therefore, by determining that the current temperature deviation of the temperature-controlled chamber is less than the preset temperature deviation, the target constant temperature pre-balance opening lookup table can be determined by using the current bypass mode of the refrigeration system and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table. This allows the current preset opening of the electronic expansion valve in the temperature-controlled chamber to obtain a reasonable preset opening value for the electronic expansion valve, thereby achieving pre-adjustment and release of the cooling capacity. This effectively suppresses the temperature overshoot in the temperature-controlled chamber, shortens the time to enter the constant temperature state, and achieves rapid and stable temperature control of the chamber, enabling rapid attainment of the test state and improving user testing efficiency. Furthermore, when it is determined that the current temperature deviation of the temperature-controlled compartment is less than the preset temperature deviation, the current bypass mode of the refrigeration system is determined, and the target constant temperature pre-balance opening lookup table is determined based on the correspondence between the bypass mode and the preset bypass mode and the preset constant temperature pre-balance opening lookup table. The reasonable preset opening value of the electronic expansion valve in the temperature-controlled compartment is then determined. Since different bypass modes correspond to different constant temperature pre-balance opening lookup tables, the corresponding constant temperature pre-balance lookup table can be determined based on the actual bypass mode operating conditions of the refrigeration system. Then, the reasonable preset opening value of the electronic expansion valve can be further determined based on the constant temperature pre-balance lookup table.

[0094] Figure 6This is a schematic diagram of a refrigeration system provided in an embodiment of the present invention. Optionally, the refrigeration system includes at least a first hot gas bypass solenoid valve, a second hot gas bypass solenoid valve, and a cold gas bypass solenoid valve; determining the current bypass mode of the refrigeration system includes: determining the current bypass mode of the refrigeration system based on the on / off states of the first hot gas bypass solenoid valve, the second hot gas bypass solenoid valve, and the cold gas bypass solenoid valve.

[0095] The environmental testing equipment consists of a chamber, a control system, and a refrigeration system. The chamber is primarily constructed of thermal insulation material, and the temperature within the chamber can be adjusted arbitrarily within a specified range. The control system comprises a touchscreen, a PLC controller, temperature sensors, pressure sensors, and related expansion modules. (Reference) Figure 6 The refrigeration system mainly consists of a compressor (COMP), a condenser (COND), an evaporator (EVAP), an electronic expansion valve (EEV), a heater (HT), a condenser fan (FAN1), a circulating fan (FAN2), solenoid valves, and capillary tubes. The principle of the refrigeration system is as follows: Figure 6 As shown, the cooling process is as follows: the high-temperature, high-pressure gaseous refrigerant at the compressor COMP outlet enters the condenser COND and condenses into liquid refrigerant. It then passes through the electronic expansion valve EEV, where its pressure is reduced to the evaporator EVAP inlet, where it vaporizes and absorbs heat for cooling. The system is equipped with a heater HT. When the chamber temperature approaches the target temperature, the PID control of the heater HT is activated to adjust the heat load, achieving precise temperature control within the chamber. In cooling mode, the electronic expansion valve EEV dynamically adjusts its opening based on the superheat at the evaporator EVAP outlet. When the external load is very low, the superheat at the evaporator EVAP outlet decreases, potentially leading to low or even zero cooling output from the refrigeration system. Therefore, a hot gas bypass circuit is typically used to unload energy from the refrigeration system to maintain the minimum suction pressure. Furthermore, to maintain a reasonable suction temperature for the compressor and prevent overheating, the refrigeration system may also be equipped with a cold gas bypass circuit. For example, Figure 6 A hot gas bypass circuit consisting of a first hot gas bypass solenoid valve SV1, a second hot gas bypass solenoid valve SV2, a first hot gas bypass capillary tube CAP1, and a second hot gas bypass capillary tube CAP2 is shown, as well as a cold gas bypass circuit consisting of a cold gas bypass solenoid valve SV3 and a cold gas bypass capillary tube CAP3. Furthermore, see reference... Figure 6 The refrigeration system also includes an ambient temperature sensor ST1, an evaporator outlet temperature sensor ST2, a compartment temperature sensor ST3, and an evaporator outlet pressure sensor SP.

[0096] Figure 7This is a schematic diagram illustrating the distribution of various bypass modes in a refrigeration system provided in this embodiment of the invention. For example, taking a refrigeration system equipped with a first hot gas bypass solenoid valve SV1, a second hot gas bypass solenoid valve SV2, and a cold gas bypass solenoid valve SV3, the refrigeration system can be classified into eight bypass modes based on their on / off states. The specific details of each bypass mode are as follows: Figure 7 As shown in the diagram. "1" represents the solenoid valve being ON, and "0" represents the solenoid valve being OFF. For example, in the fourth bypass mode MODF_bypass3, the first hot gas bypass solenoid valve SV1 is ON, the second hot gas bypass solenoid valve SV2 is OFF, and the cold gas bypass solenoid valve SV3 is OFF.

[0097] It should be noted that the various bypass modes included in the refrigeration system are related to the specific structure of the thermal bypass circuit and / or cold bypass circuit of the refrigeration system. The eight cases listed here are only illustrative examples, and the specific settings can be made according to the actual situation. No specific limitations are made here.

[0098] The correspondence between the preset bypass mode and the preset thermostatic pre-balancing opening lookup table is one-to-one. That is, for each bypass mode MODE_bypassi, a corresponding electronic expansion valve thermostatic pre-balancing opening lookup table is set. When the bypass mode MODE_bypassi changes, simply select the corresponding thermostatic pre-balancing opening lookup table according to the correspondence between the preset bypass mode and the preset thermostatic pre-balancing opening lookup table to calculate the current preset opening value Deevi_j_t of the electronic expansion valve. Specifically:

[0099] When MODE_bypassi = MODE_bypass0, Deevi_j_t = Deevi_j, mb0;

[0100] When MODE_bypassi = MODE_bypass1, Deevi_j_t = Deevi_j,mb1;

[0101] When MODE_bypassi = MODE_bypass2, Deevi_j_t = Deevi_j,mb2;

[0102] When MODE_bypassi = MODE_bypass3, Deevi_j_t = Deevi_j,mb3;

[0103] When MODE_bypassi = MODE_bypass4, Deevi_j_t = Deevi_j,mb4;

[0104] When MODE_bypassi = MODE_bypass5, Deevi_j_t = Deevi_j,mb5;

[0105] When MODE_bypassi = MODE_bypass6, Deevi_j_t = Deevi_j,mb6;

[0106] When MODE_bypassi = MODE_bypass7, Deevi_j_t = Deevi_j, mb7.

[0107] Figures 8-15 These are schematic diagrams of the isothermal pre-balancing opening lookup tables corresponding to bypass modes 1-8, respectively. In bypass mode 1, i.e., when MODE_bypassi = MODE_bypass0, Deevi_j and mb0 are determined according to... Figure 8 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 2, i.e., when MODE_bypassi = MODE_bypass1, Deevi_j,mb1 is calculated according to... Figure 9 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 3, i.e., when MODE_bypassi = MODE_bypass2, Deevi_j,mb2 is calculated according to... Figure 10 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 4, i.e., when MODE_bypassi = MODE_bypass3, Deevi_j,mb3 is calculated according to... Figure 11 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 5, i.e., when MODE_bypassi = MODE_bypass4, Deevi_j,mb4 is calculated according to... Figure 12 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 6, i.e., when MODE_bypassi = MODE_bypass5, Deevi_j,mb5 is calculated according to... Figure 13 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 7, i.e., when MODE_bypassi = MODE_bypass6, Deevi_j,mb6 is calculated according to... Figure 14 The isothermal pre-balance opening lookup table shown is used for calculation; in bypass mode 8, i.e., when MODE_bypassi = MODE_bypass7, Deevi_j,mb7 is calculated according to... Figure 15 The constant temperature pre-balance opening degree lookup table shown is used for calculation.

[0108] Figure 16 This is a flowchart of a control method for another electronic expansion valve target opening control mode provided in an embodiment of the present invention. Optionally, refer to... Figure 16 The method includes:

[0109] S2501. Determine the mode number of the current bypass mode based on the current bypass mode.

[0110] Refrigeration systems typically have multiple bypass modes, the specific number of which depends on the on / off state of the solenoid valves used. The bypass mode number is assigned based on the total number of bypass modes available in the refrigeration system, and each mode number corresponds to a specific constant temperature pre-balancing opening lookup table.

[0111] S2502. Based on the current bypass mode mode number, query the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table to determine the target constant temperature pre-balance opening lookup table.

[0112] Since each bypass mode corresponding to a mode number has a corresponding constant temperature pre-balance opening lookup table, after determining that the refrigeration system has entered a quasi-constant temperature state, the corresponding mode number can be determined according to the current bypass mode of the refrigeration system. Then, based on the mode number of the bypass mode, the current constant temperature pre-balance opening lookup table can be determined by querying the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table, that is, the target constant temperature pre-balance opening lookup table can be determined.

[0113] S2503. Based on the current target temperature of the temperature-controlled room and the current external ambient temperature, determine the target selection calculation block in the target constant temperature pre-balance opening query table.

[0114] The real-time target temperature of the temperature-controlled compartment and the real-time external ambient temperature may differ under different bypass modes of the refrigeration system. Therefore, the corresponding target selection calculation block may also be different. Thus, after determining the bypass mode of the refrigeration system and its corresponding target isothermal pre-balancing opening lookup table, it is also necessary to determine the current target selection calculation block based on the current target temperature of the temperature-controlled compartment and the current external ambient temperature.

[0115] Figure 17 This is a schematic diagram of the block division of a constant temperature pre-balancing opening lookup table provided in an embodiment of the present invention. Optionally, the target constant temperature pre-balancing opening lookup table consists of multiple characteristic point values ​​of the target temperature of the temperature-controlled room, multiple characteristic point values ​​of the external ambient temperature, and multiple calculation blocks divided according to each characteristic point value. Determining the target selection calculation block in the target constant temperature pre-balancing opening lookup table based on the current target temperature of the temperature-controlled room and the current external ambient temperature includes: determining the target selection calculation block based on the current target temperature of the temperature-controlled room, the current external ambient temperature, and each characteristic point value.

[0116] The constant temperature pre-balance opening lookup table is divided into calculation blocks based on the target temperature of the room and the external ambient temperature, and there should be no overlapping areas between the calculation blocks.

[0117] For example, refer to Figure 17 The target temperature of the temperature-controlled room has multiple characteristic point values, including Tisv,min, Tisv1,eevi_j, Tisv2,eevi_j, Tisv3,eevi_j, and Tisv,max; the external ambient temperature has multiple characteristic point values, including Tiat,max, Tiat2,eevi_j, Tiat1,eevi_j, and Tiat,min. The calculation blocks divided according to these characteristic point values ​​include blocks OV1-OV4, blocks OV9-OV12, and blocks 1-12.

[0118] Among them, in the various constant temperature pre-balance opening lookup tables:

[0119] Tisv1,eevi_j=INT[(Tisv2,eevi_j+Tisv,min) / 2];

[0120] Tisv2,eevi_j=INT[(Tisv2,eevi_j+Tisv,min) / 2];

[0121] Tisv3,eevi_j=INT[(Tisv,max+Tisv,min) / 2];

[0122] Tiat, max=45; Tiat, min=0; Tiat2, eevi_j=35;

[0123] Tiat1,eevi_j=25; Tisv,max=150; Tisv,min=-40.

[0124] Specifically, determining the target selection calculation block based on the current target temperature of the temperature-controlled room, the current external ambient temperature, and the values ​​of various characteristic points means that the calculation block corresponding to the current target temperature of the temperature-controlled room and / or the current external ambient temperature meeting certain characteristic point value range conditions is the target selection calculation block. For example, when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat>Tiat,max AND Tisv,min≤Tisv<Tisv1,eevi_j, then the target selection calculation block is calculation block OV1; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat>Tiat,max AND Tisv1,eevi_j≤Tisv<Tisv2,eevi_j, then the target selection calculation block is calculation block OV2; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat>Tiat,max AND Tisv2,eevi_j≤Tisv<Tisv3,eevi_j,eevi_j≤Tisv<Tisv3,eevi_j≤Tisv<Tisv1 ... When i_j, the target uses calculation block OV3; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat>Tiat,maxANDTisv3,eevi_j≤Tisv≤Tisv,max, the target uses calculation block OV4; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat2,eevi_j<Tiat≤Tiat,maxANDTisv,min≤Tisv<Tisv1,eevi_j, the target uses calculation block 1.

[0125] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat2,eevi_j<Tiat≤Tiat,maxAND

[0126] If Tisv1, eevi_j≤Tisv<Tisv2, eevi_j, then the target uses computation block 2.

[0127] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat2,eevi_j<Tiat≤Tiat,maxAND

[0128] When Tisv2, eevi_j≤Tisv<Tisv3, eevi_j, the target computation block is computation block 3;

[0129] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat2,eevi_j<Tiat≤Tiat,maxAND

[0130] When Tisv3, eevi_j≤Tisv≤Tisv,max, the target uses computation block 4.

[0131] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat1,eevi_j<Tiat≤Tiat2,eevi_jAND

[0132] When Tisv,min≤Tisv<Tisv1,eevi_j, the target computation block is computation block 5;

[0133] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiatl,eevi_j<Tiat≤Tiat2,eevi_jAND

[0134] When Tisv1, eevi_j≤Tisv<Tisv2, eevi_j, the target computation block is computation block 6.

[0135] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat1,eevi_j<Tiat≤Tiat2,eevi_jAND

[0136] When Tisv2, eevi_j≤Tisv<Tisv3, eevi_j, the target computation block is computation block 7.

[0137] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiatl,eevi_j<Tiat≤Tiat2,eevi_jAND

[0138] When Tisv3, eevi_j≤Tisv≤Tisv,max, the target computation block is computation block 8.

[0139] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat,min≤Tiat≤Tiat1,eevi_jAND

[0140] When Tisv,min≤Tisv<Tisv1,eevi_j, the target computation block is computation block 9;

[0141] When the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat,min≤Tiat≤Tiat1,eevi_jAND

[0142] When Tisv1,eevi_j≤Tisv<Tisv2,eevi_j, the target calculation block is calculation block 10; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat,min≤Tiat≤Tiat1,eevi_jAND

[0143] When Tisv2,eevi_j≤Tisv<Tisv3,eevi_j, the target calculation block is calculation block 11; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat,min≤Tiat≤Tiat1,eevi_jAND

[0144] When Tisv3, eevi_j ≤ Tisv ≤ Tisv,max, the target calculation block is calculation block 12; when the current target temperature of the temperature-controlled chamber and the current external ambient temperature satisfy: Tiat < Tiat,min AND Tisv,min ≤ Tisv < Tisv1,eevi_j, the target calculation block is calculation block OV9; when the current target temperature of the temperature-controlled chamber and the current external ambient temperature satisfy: Tiat < Tiat,min AND Tisv1,eevi_j ≤ Tisv < Tisv2,eevi_j When j, the target calculation block is selected as calculation block OV10; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat<Tiat,minANDTisv2,eevi_j≤Tisv<Tisv3,eevi_j, the target calculation block is selected as calculation block OV11; when the current target temperature of the temperature-controlled room and the current external ambient temperature satisfy: Tiat<Tiat,minANDTisv3,eevi_j≤Tisv≤Tisv,max, the target calculation block is selected as calculation block OV12.

[0145] It should be noted that the specific number and values ​​of the characteristic point values ​​included in the target temperature of the temperature-controlled room and the characteristic point values ​​included in the external ambient temperature in the constant temperature pre-balancing opening lookup table can be set according to the actual situation, and no specific limitation is made here. Similarly, the specific number of divisions of each block in the constant temperature pre-balancing opening lookup table can also be set according to the actual situation, and no specific limitation is made here.

[0146] S2504. Based on the target, select the calculation block and determine the current preset opening degree of the electronic expansion valve of the temperature control chamber according to the preset target opening degree value calculation algorithm.

[0147] Once the target calculation block is determined, it is only necessary to calculate the current preset opening degree of the electronic expansion valve in the temperature control chamber according to the preset target opening degree calculation algorithm.

[0148] Optionally, the preset target opening value calculation algorithm is as follows:

[0149]

[0150] in,

[0151]

[0152]

[0153] Where x1 is the minimum boundary value of the target temperature in the temperature-controlled chamber of the target calculation block, x2 is the maximum boundary value of the target temperature in the temperature-controlled chamber of the target calculation block, y1 is the minimum boundary value of the external ambient temperature of the target calculation block, y2 is the maximum boundary value of the external ambient temperature of the target calculation block, and f(Q) 11 f(Q) 12 f(Q) 21 f(Q) 22 The preset opening values ​​at the four vertices of the calculation block are selected for the target in turn.

[0154] Figure 18 This is a schematic diagram of bilinear interpolation provided in an embodiment of the present invention. The algorithm for calculating the preset target opening value is a bilinear interpolation algorithm, as shown in the schematic diagram below. Figure 18 As shown.

[0155] For example, assuming the target uses computation block 1, then Tisv,min represents the minimum boundary value of Tisv for the target uses computation block 1, Tisv1,eevi_j represents the maximum boundary value of Tisv for the target uses computation block 1, Tiat2,eevi_j represents the minimum boundary value of Tiat for the target uses computation block 1, and Tiat,max represents the maximum boundary value of Tiat for the target uses computation block 1. The preset values ​​of the opening at the four vertices of the target uses computation block 1 are Deevi_j,mbi_01, Deevi_j,mbi_02, Deevi_j,mbi_06, and Deevi_j,mbi_07.

[0156] but:

[0157] in,

[0158] in,

[0159] It should be noted that if calculation block 2, calculation block 3, ..., calculation block 12 are selected, the calculation principle and steps of Deevi_j_t are exactly the same as those of calculation block 1, and so on.

[0160] The implementation principle of the target opening control mode of the electronic expansion valve provided in this embodiment is as follows: First, the mode number of the current bypass mode is determined according to the current bypass mode. Then, based on the mode number of the current bypass mode, the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table is queried to determine the target constant temperature pre-balance opening lookup table. Second, the target selection calculation block is determined in the target constant temperature pre-balance opening lookup table based on the current target temperature of the temperature control chamber and the current external ambient temperature. Finally, the current preset opening of the electronic expansion valve in the temperature control chamber is determined according to the preset target opening value calculation algorithm based on the target selection calculation block. Therefore, by determining that the current temperature deviation of the temperature-controlled chamber is less than the preset temperature deviation, the target constant temperature pre-balance opening lookup table can be determined by using the current bypass mode of the refrigeration system, the bypass mode number, and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table. This allows for the determination of the current preset opening of the electronic expansion valve in the temperature-controlled chamber, thus obtaining a reasonable preset opening value for the electronic expansion valve. This enables the pre-adjustment and release of refrigeration capacity, effectively suppressing the temperature overshoot in the temperature-controlled chamber, shortening the time to reach constant temperature, achieving rapid and stable temperature control of the chamber, quickly reaching the test state, and improving user testing efficiency. Furthermore, when it is determined that the current temperature deviation of the temperature-controlled compartment is less than the preset temperature deviation, the system determines the current bypass mode of the refrigeration system and, based on the mode number of the bypass mode and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table, determines the target constant temperature pre-balance opening lookup table. Then, based on the current target temperature of the temperature-controlled compartment and the current external ambient temperature, the system selects the target calculation block from the target constant temperature pre-balance opening lookup table. Based on the target calculation block, the system calculates the reasonable preset opening value of the electronic expansion valve in the temperature-controlled compartment according to the preset target opening value calculation algorithm. Since different bypass modes correspond to different constant temperature pre-balance opening lookup tables, the corresponding constant temperature pre-balance lookup table can be determined according to the actual bypass mode operating condition of the refrigeration system. Furthermore, the reasonable preset opening value of the electronic expansion valve can be further determined based on the constant temperature pre-balance lookup table, thus enabling the refrigeration system to adapt to various operating conditions, expanding its application range and improving its applicability.

[0161] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0162] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for rapid and stable temperature control of a compartment in a refrigeration system, characterized in that, The refrigeration system includes at least a first hot gas bypass solenoid valve, a second hot gas bypass solenoid valve, and a cold gas bypass solenoid valve; the method includes: Obtain the current target temperature and the actual temperature of the temperature-controlled room; The current temperature deviation of the temperature-controlled room is obtained based on the current target temperature and the actual temperature of the temperature-controlled room; wherein, the current temperature deviation of the temperature-controlled room is the current target temperature of the temperature-controlled room minus the actual temperature of the temperature-controlled room. The current control mode of the electronic expansion valve in the temperature control chamber is determined based on the current temperature deviation and the preset temperature deviation, and the opening degree of the electronic expansion valve is adjusted according to the current control mode. If the current temperature deviation of the temperature control chamber is greater than or equal to the preset temperature deviation, then the current control mode of the electronic expansion valve of the temperature control chamber is the target opening control mode. The target opening control mode is as follows: determine the current bypass mode of the refrigeration system, and determine the target constant temperature pre-balance opening lookup table based on the current bypass mode and the correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table; obtain the current target temperature of the temperature control chamber and the current external ambient temperature, and determine the target selection calculation block in the target constant temperature pre-balance opening lookup table based on the current target temperature of the temperature control chamber and the current external ambient temperature; determine the current preset opening of the electronic expansion valve of the temperature control chamber according to the preset target opening value calculation algorithm based on the target selection calculation block; Determining the current bypass mode of the refrigeration system includes: determining the current bypass mode of the refrigeration system based on the on / off states of the first hot gas bypass solenoid valve, the second hot gas bypass solenoid valve, and the cold gas bypass solenoid valve.

2. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, The algorithm for calculating the preset target opening value is as follows: in, in, The minimum boundary value of the target temperature in the temperature-controlled chamber of the calculation block is selected as the target. The maximum boundary value of the target temperature in the temperature-controlled chamber of the calculation block is selected as the target. The minimum boundary value of the external ambient temperature of the computational block is selected for the target. The maximum boundary value of the external ambient temperature of the computational block is selected for the target. , , , The preset opening values ​​at the four vertices of the calculation block are selected for the target in turn.

3. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, The step of determining the target isostatic pre-balancing opening lookup table based on the current bypass mode and the correspondence between the preset bypass mode and the preset isostatic pre-balancing opening lookup table includes: Determine the current bypass mode number based on the current bypass mode; Based on the current bypass mode's mode number, query the correspondence between the preset bypass mode and the preset isothermal pre-balancing opening lookup table to determine the target isothermal pre-balancing opening lookup table.

4. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, The target constant temperature pre-balance opening lookup table consists of multiple characteristic point values ​​of the target temperature of the temperature-controlled room, multiple characteristic point values ​​of the external ambient temperature, and multiple calculation blocks divided according to each characteristic point value. The step of determining the target selection calculation block based on the current target temperature of the temperature-controlled room and the current external ambient temperature in the target constant temperature pre-equilibrium opening lookup table includes: The target selection calculation block is determined based on the current target temperature of the temperature-controlled room, the current external ambient temperature, and the values ​​of each feature point.

5. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, After adjusting the opening degree of the electronic expansion valve according to the current control mode, the method further includes: Determine whether the current target temperature has changed, and if it has changed, return to execute the operation of obtaining the current temperature deviation of the temperature control room based on the current target temperature of the temperature control room and the actual temperature of the temperature control room until the current target temperature no longer changes.

6. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, If the current temperature deviation of the temperature control chamber is less than the preset temperature deviation, then the current control mode of the electronic expansion valve of the temperature control chamber is the superheat deviation control mode.

7. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 6, characterized in that, The superheat deviation control mode is as follows: The system obtains the current superheat and target superheat of the evaporator; and performs PID control on the opening of the electronic expansion valve based on the deviation between the current superheat and target superheat of the evaporator.

8. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 1, characterized in that, The correspondence between the preset bypass mode and the preset constant temperature pre-balance opening lookup table is a one-to-one correspondence.

9. The method for rapid and stable temperature control of a refrigeration system compartment according to claim 3, characterized in that, The bypass mode number is determined based on the total number of bypass modes in the refrigeration system, and each bypass mode corresponding to a mode number has a corresponding constant temperature pre-balance opening lookup table.

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