A humidity control system with reduced energy consumption

Abstract

The application discloses a humidity control system capable of reducing energy consumption and belongs to the technical field of humidity adjustment of environmental test equipment. The humidity control system comprises a test box body, an evaporator, a heater, a humidification system, a temperature sensor and a humidity sensor arranged in the test box body, a first refrigerating system, a second refrigerating system, a controller and a man-machine interaction module arranged outside the test box body, wherein the first refrigerating system, the second refrigerating system, the heater, the humidification system, the temperature sensor, the humidity sensor and the man-machine interaction module are connected with the controller, the first refrigerating system and the second refrigerating system are connected with the evaporator, the first refrigerating system is used for fast cooling and deep dehumidification working conditions, the refrigerating capacity of the second refrigerating system is less than that of the first refrigerating system, and the second refrigerating system is used for accurate humidity adjustment. Through the cooperation of double compressors and model predictive control, high-precision humidity adjustment is realized, energy consumption is significantly reduced, the service life of the compressor is prolonged, and the humidity control system has self-adaptive capacity.

Description

Technical Field

[0001] This invention relates to the field of humidity control technology for environmental testing equipment, and more specifically to a humidity control system that can reduce energy consumption. Background Technology

[0002] Constant temperature and humidity test chambers are widely used in industries such as electronics, aerospace, automotive, and materials to simulate extreme environments such as high temperature and high humidity, and low temperature and low humidity, in order to test the reliability and durability of products under different temperature and humidity conditions. Under high temperature and high humidity conditions, such as when the temperature is set to 85 degrees Celsius and the relative humidity is set to 85%, the test chamber needs to continuously perform a small amount of dehumidification to counteract the water vapor generated by the humidification system, thereby maintaining a constant humidity.

[0003] In existing technologies, a single high-power refrigeration compressor is commonly used for refrigeration and dehumidification. This approach has the following technical drawbacks: First, the humidity control accuracy is low. To meet the rapid cooling requirements of the test chamber, the compressors configured are usually very powerful. During the high temperature and high humidity steady-state maintenance phase, even with cooling capacity adjustment through methods such as hot gas bypass, the residual cooling capacity is still far greater than the actual required dehumidification capacity, resulting in dehumidification overshoot and drastic humidity fluctuations, making it difficult to meet the requirements of high-end testing for precise humidity control.

[0004] Second, there is serious energy waste. High-power compressors operate for long periods at low load rates or are frequently started and stopped, resulting in extremely low operating efficiency, causing huge energy waste and increasing testing costs.

[0005] Third, the lifespan of the compressor is shortened. High-power compressors are often in an underutilized working condition, leading to increased wear and tear on mechanical components and control systems, higher failure rates, and decreased overall reliability.

[0006] Some existing technologies attempt to use dual-compressor switching control, but their switching logic is simple, typically deciding whether to turn the large compressor on or off based solely on whether the humidity error exceeds a fixed threshold. This lacks the ability to predict future humidity trends and still suffers from problems such as response lag and low energy efficiency. Furthermore, existing solutions fail to fully integrate the system's dynamic characteristics for online adaptive adjustment, making it difficult to meet the optimal control requirements under different loads and environmental conditions.

[0007] Therefore, there is an urgent need to provide an intelligent humidity control technology that can achieve high precision, low energy consumption, and long lifespan to overcome the shortcomings of the existing technologies. Summary of the Invention

[0008] The purpose of this invention is to provide a humidity control system that can reduce energy consumption. Through dual compressor collaboration and model predictive control, it achieves high-precision humidity regulation, significantly reduces energy consumption, extends compressor life, and has adaptive capabilities.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A humidity control system with reduced energy consumption includes: a first refrigeration system, a second refrigeration system, an evaporator, a test chamber, a heater, a humidification system, a temperature sensor, a humidity sensor, a controller, and a human-machine interface module. The evaporator, heater, humidification system, temperature sensor, and humidity sensor are installed inside the test chamber, while the first refrigeration system, second refrigeration system, controller, and human-machine interface module are installed outside the test chamber. The first refrigeration system, second refrigeration system, heater, humidification system, temperature sensor, humidity sensor, and human-machine interface module are connected to the controller. Both the first and second refrigeration systems are connected to the evaporator. The first refrigeration system is used for rapid cooling and deep dehumidification. The second refrigeration system has a smaller cooling capacity than the first refrigeration system and is used for precise humidity regulation. The controller is configured to perform the following humidity coordination control steps: Step 1: Establish a discrete-time state-space prediction model for humidity changes inside the test chamber, and use the recursive least squares method to identify the parameters of the discrete-time state-space prediction model online. Step 2: In each control cycle, based on the current humidity state, historical control inputs, and discrete-time state-space prediction model, the optimal control sequence in the finite time domain is solved by a rolling time-domain optimizer. Step 3: Implement humidity control based on the optimal control sequence.

[0010] Further, the first refrigeration system includes a first compressor, a first ball valve, a first manual expansion valve, a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, a thermostatic expansion valve, a first oil separator, a first dryer filter, and a first sight glass. The input end of the first compressor is connected to the first ball valve, the first manual expansion valve, the first solenoid valve, the output end of the evaporator, and the thermostatic expansion valve. The output end of the first compressor is connected to the first inlet of the water-cooled condenser and the second solenoid valve through the first oil separator. The second solenoid valve is connected to the first ball valve. The first outlet of the water-cooled condenser is sequentially connected to the first dryer filter and the first sight glass. The first sight glass is connected to the third, fourth, and fifth solenoid valves. The third solenoid valve is connected to the first manual expansion valve. The fourth solenoid valve is connected to the first electronic expansion valve. The first electronic expansion valve is connected to the first input end of the evaporator. The fifth solenoid valve is connected to the input end of the thermostatic expansion valve. The output end of the thermostatic expansion valve is connected to the first input end of the heat exchanger and the first solenoid valve. The first output end of the heat exchanger is connected to the input end of the first compressor.

[0011] Furthermore, the output end of the first compressor is connected to a high-pressure gauge and a high-pressure controller, the input end of the first compressor is connected to a high-pressure gauge and a needle valve, the output end of the first compressor is connected to the inlet of the first oil separator, the outlet of the first oil separator is connected to the first inlet of the water-cooled condenser, the return port of the first oil separator is connected to a third sight glass, the third sight glass is connected to a first constant pressure valve, and the first constant pressure valve is connected to the return port of the first compressor.

[0012] Furthermore, a needle valve is connected to the first outlet of the water-cooled condenser.

[0013] Furthermore, the first output end of the evaporator is connected to the input end of the first compressor via a check valve.

[0014] Furthermore, the second refrigeration system includes a second compressor, a second manual expansion valve, a second ball valve, a first capillary tube, a second capillary tube, a third capillary tube, a second oil separator, a sixth solenoid valve, a seventh solenoid valve, an eighth solenoid valve, a ninth solenoid valve, a tenth solenoid valve, and an eleventh solenoid valve. The input end of the second compressor is connected to the second output end of the evaporator, the second manual expansion valve, the second ball valve, and the first capillary tube. The output end of the second compressor is connected to the second inlet of the water-cooled condenser through the second oil separator. The second outlet of the water-cooled condenser is connected to the sixth solenoid valve, the seventh solenoid valve, and the second input end of the heat exchanger. The sixth solenoid valve is connected to the first pressure relief tank, the first pressure relief tank is connected to the first capillary tube, the seventh solenoid valve is connected to the second ball valve, the second output end of the plate heat exchanger is connected to the second drying filter, the second drying filter is connected to the eighth and ninth solenoid valves, the eighth solenoid valve is connected to the second manual expansion valve, the ninth solenoid valve is connected to the tenth and eleventh solenoid valves and the second capillary tube, the tenth solenoid valve is connected to the third manual expansion valve, the eleventh solenoid valve is connected to the third capillary tube, and the second capillary tube, the third manual expansion valve and the third capillary tube are connected to the second input end of the evaporator.

[0015] Furthermore, the input end of the second compressor is connected to a high-pressure gauge and a needle valve, the output end of the second compressor is connected to a high-pressure gauge and a high-pressure controller, the output end of the second compressor is connected to the inlet of the second oil separator, the outlet of the second oil separator is connected to the second inlet of the water-cooled condenser, the return port of the second oil separator is connected to a third sight glass, the third sight glass is connected to a second constant pressure valve, and the second constant pressure valve is connected to the return port of the second compressor.

[0016] Furthermore, a needle valve is connected to the second outlet of the water-cooled condenser.

[0017] Further, in step 1, the discrete-time state-space prediction model is: ; ; In the formula, the state variable , This refers to the real-time relative humidity inside the test chamber. Real-time surface temperature of the shared evaporator; control input variables , This indicates the start / stop status of the first compressor. The target cooling capacity of the second compressor; disturbance input This represents the humidification power of the humidification system at the current moment. , , A matrix containing the parameters of the system to be identified. and These are process noise and measurement noise, respectively. for The output matrix.

[0018] Furthermore, in step 2, the optimal control sequence in the finite time domain is solved using a rolling time-domain optimizer, specifically as follows: The optimization problem is defined as follows: The prediction time domain length is The control time domain length is ,and The reference humidity sequence is defined as follows: ,in The target humidity is set by the experiment. Optimize objective function The design aims to simultaneously minimize humidity tracking error, control energy consumption, and the number of first compressor switching cycles, as follows: ; In the formula, Indicates in Time prediction Humidity value at any given time; This is a semi-positive definite state weight matrix used to adjust the humidity tracking accuracy; It is a positive definite control weight matrix used to regulate cooling energy consumption; This is the switching penalty coefficient for the first compressor, used to suppress frequent start-stop of the first compressor and extend its lifespan; The optimization variable is the control input sequence in the control time domain. ; The constraints include: First compressor state constraint: ; Second compressor power constraint: , This is the minimum sustainable cooling capacity of the second compressor. This is the rated power of the second compressor; Humidity safety constraints: , The minimum safe humidity level is set to prevent the inside of the chamber from becoming too dry; System dynamic constraints: Discrete-time state-space prediction model; The problem is solved using a mixed-integer quadratic programming solver, which constitutes a standard mixed-integer quadratic programming problem. The solver outputs the optimal control sequence.

[0019] In summary, the present invention has at least one of the following beneficial technical effects: First, it significantly improves humidity control accuracy. This invention employs a hardware architecture where a first refrigeration system and a second refrigeration system work together. The second refrigeration system has a smaller cooling capacity than the first and is specifically designed for precise humidity regulation. The invention integrates a rolling time-domain optimization algorithm based on a discrete-time state-space prediction model into the controller. This model can describe the dynamic coupling relationship between humidity and evaporator temperature within the test chamber in real time, and identifies model parameters online using recursive least squares, ensuring the model always closely matches the actual characteristics of the current system. In each control cycle, the controller solves for the optimal control sequence within a finite time domain based on the current humidity state and the prediction model, thereby predicting future humidity trends in advance. This avoids the overshoot or undershoot phenomena caused by lag in traditional feedback control, enabling stable and high-precision humidity control.

[0020] Secondly, it significantly reduces system energy consumption. The optimization objective function of this invention simultaneously considers humidity tracking error, control energy consumption, and the number of switching operations of the first compressor. A mixed-integer quadratic programming solver obtains the control command that minimizes the overall cost in each control cycle. Under high-temperature and high-humidity steady-state conditions, the controller can intelligently decide to activate only the second refrigeration system and operate it at optimal cooling power, avoiding high power waste of the first compressor. Simultaneously, due to the use of predictive control, the system can adjust the cooling output in advance, reducing energy loss caused by ineffective cooling and excessive dehumidification. Actual testing shows a significant energy-saving effect compared to existing single-compressor solutions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the control flow of the humidity control system of the present invention that can reduce energy consumption; Figure 2 This is a schematic diagram of the first and second refrigeration systems.

[0022] Reference numerals: 1. First compressor; 2. First ball valve; 3. First manual expansion valve; 4. First solenoid valve; 5. Evaporator; 6. Thermal expansion valve; 7. First oil separator; 8. Water-cooled condenser; 9. Second solenoid valve; 10. First dryer filter; 11. First sight glass; 12. Third solenoid valve; 13. Fourth solenoid valve; 14. Fifth solenoid valve; 15. First electronic expansion valve; 16. Plate heat exchanger; 17. High pressure gauge; 18. High pressure controller; 19. Needle valve; 20. Second sight glass; 21. First constant pressure valve 21. Pressure valve; 22. Check valve; 23. Second compressor; 24. Second manual expansion valve; 25. Second ball valve; 26. First capillary tube; 27. Second oil separator; 28. Sixth solenoid valve; 29. ​​Seventh solenoid valve; 30. First pressure relief tank; 31. Eighth solenoid valve; 32. Ninth solenoid valve; 33. Tenth solenoid valve; 34. Eleventh solenoid valve; 35. Second capillary tube; 36. Third manual expansion valve; 37. Third capillary tube; 38. Third sight glass; 39. Second constant pressure valve; 40. Second dryer filter. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] This invention provides a humidity control system with reduced energy consumption, comprising: a first refrigeration system, a second refrigeration system, an evaporator, a test chamber, a heater, a humidification system, a temperature sensor, a humidity sensor, a controller, and a human-machine interface module. The evaporator, heater, humidification system, temperature sensor, and humidity sensor are disposed inside the test chamber, while the first refrigeration system, second refrigeration system, controller, and human-machine interface module are disposed outside the test chamber. The first refrigeration system, second refrigeration system, heater, humidification system, temperature sensor, humidity sensor, and human-machine interface module are connected to the controller. Both the first and second refrigeration systems are connected to the evaporator. The first refrigeration system is used for rapid cooling and deep dehumidification. The second refrigeration system has a lower cooling capacity than the first refrigeration system and is used for precise humidity regulation. like Figure 1 As shown, the controller is configured to perform the following humidity coordination control steps: Step 1: Establish a discrete-time state-space prediction model for humidity changes inside the test chamber, and use the recursive least squares method to identify the parameters of the discrete-time state-space prediction model online. Step 2: In each control cycle, based on the current humidity status, historical control inputs, and discrete-time state-space prediction model, the optimal control sequence in the finite time domain is solved by a rolling time-domain optimizer. Step 3: Implement humidity control based on the optimal control sequence.

[0025] The first and second refrigeration systems will be described next, and their structures are as follows: Figure 2 As shown; The first refrigeration system includes a first compressor 1, a first ball valve 2, a first manual expansion valve 3, a first solenoid valve 4, a second solenoid valve 9, a third solenoid valve 12, a fourth solenoid valve 13, a fifth solenoid valve 14, a thermostatic expansion valve 6, a first oil separator 7, a first dryer filter 10, and a first sight glass 11. The input end of the first compressor 1 is connected to the first ball valve 2, the first manual expansion valve 3, the first solenoid valve 4, the output end of the evaporator 5, and the thermostatic expansion valve 6. The output end of the first compressor 1 is connected to the first inlet of the water-cooled condenser 8 and the second solenoid valve 9 through the first oil separator 7. The second solenoid valve 9 is connected to the first ball valve 2. The first outlet of the water-cooled condenser 8 is sequentially connected to the first dryer filter 10 and the first sight glass 11. The first sight glass 11 is connected to the third solenoid valve 12, the fourth solenoid valve 13 and the fifth solenoid valve 14. The third solenoid valve 12 is connected to the first manual expansion valve 3. The fourth solenoid valve 13 is connected to the first electronic expansion valve 15. The first electronic expansion valve 15 is connected to the first input terminal of the evaporator 5. The fifth solenoid valve 14 is connected to the input terminal of the thermal expansion valve 6. The output terminal of the thermal expansion valve 6 is connected to the first input terminal of the plate heat exchanger 16 and the first solenoid valve 4. The first output terminal of the plate heat exchanger 16 is connected to the input terminal of the first compressor 1.

[0026] The output end of the first compressor 1 is connected to a high-pressure gauge 17 and a high-pressure controller 18. The input end of the first compressor 1 is connected to a high-pressure gauge 17 and a needle valve 19. The output end of the first compressor 1 is connected to the inlet of the first oil separator 7. The outlet of the first oil separator 7 is connected to the first inlet of the water-cooled condenser 8. The return port of the first oil separator 7 is connected to a third sight glass 38. The third sight glass 38 is connected to a first constant pressure valve 21. The first constant pressure valve 21 is connected to the return port of the first compressor 1.

[0027] The first outlet of the water-cooled condenser 8 is connected to a needle valve 19.

[0028] The first output end of the evaporator 5 is connected to the input end of the first compressor 1 via a check valve 22.

[0029] The second refrigeration system includes a second compressor 23, a second manual expansion valve 24, a second ball valve 25, a first capillary tube 26, a second capillary tube 35, a third capillary tube 37, a second oil separator 27, a sixth solenoid valve 28, a seventh solenoid valve 29, an eighth solenoid valve 31, a ninth solenoid valve 32, a tenth solenoid valve 33, and an eleventh solenoid valve 34. The input end of the second compressor 23 is connected to the second output end of the evaporator 5, the second manual expansion valve 24, the second ball valve 25, and the first capillary tube 26. The output end of the second compressor 23 is connected to the second inlet of the water-cooled condenser 8 through the second oil separator 27. The second outlet of the water-cooled condenser 8 is connected to the sixth solenoid valve 28, the seventh solenoid valve 29, and the second input end of the heat exchanger 16. Solenoid valve 28 is connected to the first pressure relief tank 30, the first pressure relief tank 30 is connected to the first capillary tube 26, the seventh solenoid valve 29 is connected to the second ball valve 25, the second output end of the plate heat exchanger 16 is connected to the second dryer filter 40, the second dryer filter 40 is connected to the eighth solenoid valve 31 and the ninth solenoid valve 32, the eighth solenoid valve 31 is connected to the second manual expansion valve 24, the ninth solenoid valve 32 is connected to the tenth solenoid valve 33, the eleventh solenoid valve 34 and the second capillary tube 35, the tenth solenoid valve 33 is connected to the third manual expansion valve 36, the eleventh solenoid valve 34 is connected to the third capillary tube 37, and the second capillary tube 35, the third manual expansion valve 36 and the third capillary tube 37 are connected to the second input end of the evaporator 5.

[0030] The input end of the second compressor 23 is connected to a high-pressure gauge 17 and a needle valve 19. The output end of the second compressor 23 is connected to a high-pressure gauge 17 and a high-pressure controller 18. The output end of the second compressor 23 is connected to the inlet of the second oil separator 27. The outlet of the second oil separator 27 is connected to the second inlet of the water-cooled condenser 8. The return port of the second oil separator 27 is connected to a third sight glass 38. The third sight glass 38 is connected to a second constant pressure valve 39. The second constant pressure valve 39 is connected to the return port of the second compressor 23.

[0031] The second outlet of the water-cooled condenser 8 is connected to a needle valve 19.

[0032] Next, the cooperative control method configured by the controller will be described in detail: In step 1, a discrete-time state-space prediction model for humidity changes within the test chamber is established. The parameters of the discrete-time state-space prediction model are then identified online using the recursive least squares method. Specifically: The specific construction process of the discrete-time state-space prediction model is as follows: Define the system in The state variable at time t is ,in The real-time relative humidity inside the test chamber, in units of... ; This represents the real-time surface temperature of the shared evaporator, in degrees Celsius.

[0033] Define the control input variable as ,in This indicates the start / stop status of the first compressor, with a value of 0 or 1, where 0 represents off and 1 represents on. The target cooling power of the second compressor is expressed in kilowatts, and its value range is as follows: , This is the minimum sustainable cooling capacity of the second compressor. Its rated power.

[0034] Define the disturbance input as This represents the humidification power of the humidification system at the current moment, measured in kilowatts, and is read in real time from the humidification system by the controller.

[0035] The discrete-time state-space prediction model consists of the following discrete state equations and output equations: ; ; In the formula, for The state transition matrix, The control input matrix, for The perturbation input matrix, for The output matrix, and These represent process noise and measurement noise, respectively. (Matrix) , , The non-zero elements in the table represent the system parameters to be identified, specifically including the influence coefficient of humidity on its own state. The influence coefficient of evaporator temperature on humidity The influence coefficient of humidity on evaporator temperature The influence coefficient of evaporator temperature on its own state The influence coefficient of the first compressor on humidity The influence coefficient of the second compressor on humidity The influence coefficient of the first compressor on the evaporator temperature The influence coefficient of the second compressor on the evaporator temperature The influence coefficient of humidification power on humidity The influence coefficient of humidification power on evaporator temperature .

[0036] The above-mentioned parameters to be identified constitute a parameter vector. Online identification is performed using recursive least squares with a forgetting factor. The recursive formula is as follows: ; ; ; in, Let be the parameter estimation vector at time k. The regression vector is composed of historical input and output data. For the gain vector, Let covariance matrix be the variance matrix. This is the forgetting factor, with a value ranging from 0.95 to 0.995. It is an identity matrix.

[0037] In step 2, during each control cycle, based on the current humidity state, historical control inputs, and the discrete-time state-space prediction model, the optimal control sequence within the finite time domain is solved using a rolling time-domain optimizer, specifically: The optimization problem of the rolling temporal optimizer is defined as follows: The prediction time domain length is The control time domain length is ,and The reference humidity sequence is defined as follows: ,in The target humidity is set by the experiment. Optimize objective function The design aims to simultaneously minimize humidity tracking error, control energy consumption, and the number of first compressor switching cycles, as follows: ; In the formula, Indicates in Time prediction Humidity value at any given time; This is a semi-positive definite state weight matrix used to adjust the humidity tracking accuracy; It is a positive definite control weight matrix used to regulate cooling energy consumption; This is the switching penalty coefficient for the first compressor, used to suppress frequent start-stop of the first compressor and extend its lifespan; The optimization variable is the control input sequence in the control time domain. ; The constraints include: First compressor state constraints: ; Second compressor power constraint: ; Humidity safety constraints: , The minimum safe humidity level is set to prevent the inside of the box from becoming too dry; System dynamic constraints: the discrete-time state-space prediction model constructed in step 1; The rolling time-domain optimizer uses a mixed-integer quadratic programming solver because the objective function is quadratic, the constraints are linear equality and inequality expressions, and it includes binary variables. This constitutes a standard mixed-integer quadratic programming problem. The solver outputs the optimal control sequence. .

[0038] In step 3, humidity control is achieved based on the optimal control sequence, specifically as follows: The controller starts from the optimal control sequence. Extract the first control command Then execute: like If the value is 0, the first compressor will start; if the value is 0, the first compressor will be shut down.

[0039] At the same time, the actual operating power of the second compressor is adjusted by a frequency converter or electronic expansion valve to make its target value equal to... .

[0040] At the next sampling time The controller re-acquires the actual humidity inside the test chamber. and evaporator temperature Update the state vector Simultaneously, update the regression vector in parameter identification. Then, a recursive least squares step is performed to obtain the updated model parameters. Then, with To form a new initial state, repeat the above steps to form a closed-loop predictive control.

[0041] Regarding the control of other components, existing technologies can be used, and this application does not impose specific limitations on them.

[0042] Embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0043] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0044] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0045] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0046] Contents not described in detail in this specification are prior art known to those skilled in the art. It is hereby indicated that the above description is intended to help those skilled in the art understand this invention, but does not limit the scope of protection of this invention. Any equivalent substitutions, modifications, improvements, or simplifications of the above descriptions that do not depart from the essential content of this invention fall within the scope of protection of this invention.

Claims

1. A humidity control system that reduces energy consumption, characterized in that, include: The test chamber comprises a first refrigeration system, a second refrigeration system, an evaporator, a test chamber, a heater, a humidification system, a temperature sensor, a humidity sensor, a controller, and a human-machine interface module. The evaporator, heater, humidification system, temperature sensor, and humidity sensor are installed inside the test chamber. The first refrigeration system, second refrigeration system, controller, and human-machine interface module are installed outside the test chamber. The first refrigeration system, second refrigeration system, heater, humidification system, temperature sensor, humidity sensor, and human-machine interface module are connected to the controller. Both the first and second refrigeration systems are connected to the evaporator. The first refrigeration system is used for rapid cooling and deep dehumidification. The second refrigeration system has a smaller cooling capacity than the first refrigeration system and is used for precise humidity regulation. The controller is configured to perform the following humidity coordination control steps: Step 1: Establish a discrete-time state-space prediction model for humidity changes inside the test chamber, and use the recursive least squares method to identify the parameters of the discrete-time state-space prediction model online. Step 2: In each control cycle, based on the current humidity status, historical control inputs, and discrete-time state-space prediction model, the optimal control sequence in the finite time domain is solved by a rolling time-domain optimizer. Step 3: Implement humidity control based on the optimal control sequence.

2. The humidity control system with reduced energy consumption according to claim 1, characterized in that, The first refrigeration system includes a first compressor, a first ball valve, a first manual expansion valve, a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, a thermostatic expansion valve, a first oil separator, a first dryer filter, and a first sight glass. The input end of the first compressor is connected to the first ball valve, the first manual expansion valve, the first solenoid valve, the output end of the evaporator, and the thermostatic expansion valve. The output end of the first compressor is connected to the first inlet of the water-cooled condenser and the second solenoid valve through the first oil separator. The second solenoid valve is connected to the first ball valve. The first outlet of the water-cooled condenser is sequentially connected to the first dryer filter and the first sight glass. The first sight glass is connected to the third, fourth, and fifth solenoid valves. The third solenoid valve is connected to the first manual expansion valve. The fourth solenoid valve is connected to the first electronic expansion valve. The first electronic expansion valve is connected to the first input end of the evaporator. The fifth solenoid valve is connected to the input end of the thermostatic expansion valve. The output end of the thermostatic expansion valve is connected to the first input end of the heat exchanger and the first solenoid valve. The first output end of the heat exchanger is connected to the input end of the first compressor.

3. A humidity control system with reduced energy consumption according to claim 2, characterized in that, The output end of the first compressor is connected to a high-pressure gauge and a high-pressure controller. The input end of the first compressor is connected to a high-pressure gauge and a needle valve. The output end of the first compressor is connected to the inlet of the first oil separator. The outlet of the first oil separator is connected to the first inlet of the water-cooled condenser. The return port of the first oil separator is connected to a third sight glass. The third sight glass is connected to a first constant pressure valve. The first constant pressure valve is connected to the return port of the first compressor.

4. A humidity control system with reduced energy consumption according to claim 2, characterized in that, The first outlet of the water-cooled condenser is connected to a needle valve.

5. A humidity control system with reduced energy consumption according to claim 2, characterized in that, The first output terminal of the evaporator is connected to the input terminal of the first compressor via a check valve.

6. A humidity control system with reduced energy consumption according to claim 2, characterized in that, The second refrigeration system includes a second compressor, a second manual expansion valve, a second ball valve, a first capillary tube, a second capillary tube, a third capillary tube, a second oil separator, a sixth solenoid valve, a seventh solenoid valve, an eighth solenoid valve, a ninth solenoid valve, a tenth solenoid valve, and an eleventh solenoid valve. The input end of the second compressor is connected to the second output end of the evaporator, the second manual expansion valve, the second ball valve, and the first capillary tube. The output end of the second compressor is connected to the second inlet of the water-cooled condenser through the second oil separator. The second outlet of the water-cooled condenser is connected to the sixth solenoid valve, the seventh solenoid valve, and the second input end of the heat exchanger. The sixth solenoid valve is connected to the first pressure relief tank, which is connected to the first capillary tube. The seventh solenoid valve is connected to the second ball valve. The second output end of the plate heat exchanger is connected to the second drying filter. The second drying filter is connected to the eighth and ninth solenoid valves. The eighth solenoid valve is connected to the second manual expansion valve. The ninth solenoid valve is connected to the tenth and eleventh solenoid valves and the second capillary tube. The tenth solenoid valve is connected to the third manual expansion valve. The eleventh solenoid valve is connected to the third capillary tube. The second capillary tube, the third manual expansion valve, and the third capillary tube are connected to the second input end of the evaporator.

7. A humidity control system with reduced energy consumption according to claim 6, characterized in that, The input end of the second compressor is connected to a high-pressure gauge and a needle valve. The output end of the second compressor is connected to a high-pressure gauge and a high-pressure controller. The output end of the second compressor is connected to the inlet of the second oil separator. The outlet of the second oil separator is connected to the second inlet of the water-cooled condenser. The return port of the second oil separator is connected to a third sight glass. The third sight glass is connected to a second constant pressure valve. The second constant pressure valve is connected to the return port of the second compressor.

8. A humidity control system with reduced energy consumption according to claim 6, characterized in that, The second outlet of the water-cooled condenser is connected to a needle valve.

9. A humidity control system with reduced energy consumption according to claim 1, characterized in that, In step 1, the discrete-time state-space prediction model is: ； ； In the formula, the state variable , This refers to the real-time relative humidity inside the test chamber. Real-time surface temperature of the shared evaporator; control input variables , This indicates the start / stop status of the first compressor. The target cooling capacity of the second compressor; disturbance input This represents the humidification power of the humidification system at the current moment. , , A matrix containing the parameters of the system to be identified. and These are process noise and measurement noise, respectively. for The output matrix.

10. A humidity control system with reduced energy consumption according to claim 9, characterized in that, In step 2, the optimal control sequence in the finite time domain is solved using a rolling time-domain optimizer, specifically as follows: The optimization problem is defined as follows: The prediction time domain length is The control time domain length is ,and The reference humidity sequence is defined as follows: ,in The target humidity is set by the experiment. Optimize objective function The design aims to simultaneously minimize humidity tracking error, control energy consumption, and the number of first compressor switching cycles, as follows: ； In the formula, Indicates in Time prediction Humidity value at any given time; This is a semi-positive definite state weight matrix used to adjust the humidity tracking accuracy; It is a positive definite control weight matrix used to regulate cooling energy consumption; This is the switching penalty coefficient for the first compressor, used to suppress frequent start-stop of the first compressor and extend its lifespan; The optimization variable is the control input sequence in the control time domain. ; The constraints include: First compressor state constraints: ; Second compressor power constraint: , This is the minimum sustainable cooling capacity of the second compressor. This is the rated power of the second compressor; Humidity safety constraints: , The minimum safe humidity level is set to prevent the inside of the chamber from becoming too dry; System dynamic constraints: Discrete-time state-space prediction model; The problem is solved using a mixed-integer quadratic programming solver, which constitutes a standard mixed-integer quadratic programming problem. The solver outputs the optimal control sequence.

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