An environmental simulation shelter test system

Abstract

This specification discloses an environmental simulation cabin testing system, including an operating console and a cabin housing the equipment under test. It also includes a refrigeration unit, a radiator, coolant piping connecting the refrigeration unit and the radiator, an air extraction device for drawing air out of the cabin, an air intake unit for controlling the air intake volume, a sensor unit, and a control unit. The sensor unit includes a first sensing module for acquiring the intake air temperature, cabin temperature, and cabin air pressure, and a second sensing module for collecting performance test data of the equipment under test. The control unit includes: a pressure regulation module that outputs a pressure control signal based on a pressure stability target and the cabin air pressure value to regulate the air intake volume of the air intake unit and the air extraction volume of the air extraction device; and a temperature regulation module that outputs a temperature control signal based on a temperature stability target, the cabin temperature value, the intake air temperature value, and the pressure control signal output by the pressure regulation module to regulate the flow rate of the coolant piping. This system achieves rapid, accurate, and coordinated control of the cabin's temperature and pressure environment.

Description

Technical Field

[0001] Several embodiments of this specification relate to the field of testing equipment technology, specifically to the optimization of an environmental simulation cabin testing system. Background Technology

[0002] A modular testing system is a specialized device used to simulate specific environmental conditions for performance verification and reliability assessment of equipment under test. It accurately replicates extreme operating conditions such as high and low temperatures and high and low air pressures within the testing chamber, providing a controlled experimental environment for the equipment. It is primarily used in industrial research and development, quality inspection, and other fields to evaluate the performance of equipment under extreme or non-standard environments.

[0003] The accuracy, stability, and response speed of the cabin environment control directly determine the accuracy and validity of the test results. Currently, the mainstream technical solution for cabin environment control generally adopts an automated control system based on a programmable logic controller (PLC), establishing independent PID (proportional-integral-derivative) closed-loop control loops for temperature and air pressure control respectively. The temperature control loop maintains the set temperature by adjusting the refrigeration unit and related valves and fans based on feedback from the cabin temperature sensor; the air pressure control loop maintains the set air pressure by controlling the speed of the intake / exhaust fans based on feedback from the cabin pressure sensor.

[0004] However, there is a strong physical coupling between cabin pressure regulation and temperature changes. In existing methods, the lack of a coordination mechanism between the two control loops results in a delayed and passive response to temperature changes only after the actual temperature change caused by the pressure fluctuations is detected. This leads to overshoot and continuous oscillations, resulting in control hysteresis, low steady-state accuracy, and poor reliability. Furthermore, these issues also prolong the time required for cabin environment setup and stabilization, impacting testing efficiency. Summary of the Invention

[0005] This specification provides an environmental simulation cabin testing system to address the problems of existing environmental simulation cabins in dealing with highly dynamic and strongly coupled testing scenarios, such as adjustment lag, large overshoot, long environmental stabilization time, and difficulty in quickly establishing and maintaining the standard temperature and pressure environment required for testing.

[0006] The technical solution is as follows:

[0007] An environmental simulation cabin testing system includes an operating table and a cabin that houses the equipment under test. It also includes a refrigeration device installed outside the cabin, a radiator installed inside the cabin, a coolant pipeline connecting the refrigeration device and the radiator, an air extraction device for extracting air from the cabin, an air intake unit for controlling the air intake volume, a sensor unit, and a control unit.

[0008] The sensor unit includes a first sensing module for acquiring inlet air temperature, cabin temperature and cabin air pressure, and a second sensing module for acquiring performance test data of the device under test.

[0009] The control unit includes a pressure regulation module and a temperature regulation module;

[0010] The air pressure regulation module outputs an air pressure control signal based on the air pressure stability target and the cabin air pressure value to regulate the air intake of the air intake unit and the air extraction of the air extraction equipment.

[0011] The temperature regulation module outputs a temperature control signal based on the temperature stability target, the cabin temperature value, the intake air temperature value, and the air pressure control signal output by the air pressure regulation module, in order to regulate the flow rate of the coolant pipeline.

[0012] As a preferred embodiment, the control unit further includes a temperature-pressure coupling module;

[0013] The temperature and pressure coupling module includes a temperature and pressure dynamic coupling model constructed based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the air pressure value inside the cabin, the air temperature value inside the cabin, the air intake temperature value, and the cabin volume; the temperature and pressure dynamic coupling model is solved, with the air pressure stability target and the temperature stability target as the constraint minimization objective function, to obtain the temperature and pressure control input sequence and its corresponding temperature and pressure change trajectory within a preset time length in the future;

[0014] The air pressure regulation module outputs an air pressure control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module and the air pressure value inside the cabin;

[0015] The temperature control module outputs a temperature control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module, the intake air temperature value, and the air pressure control signal output by the air pressure control module.

[0016] As a preferred embodiment, the sensor unit further includes a third sensing module that is connected to the device under test and monitors the disturbance of the environment inside the cabin in real time.

[0017] The temperature and pressure coupling module includes a dynamic temperature and pressure coupling model based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the cabin air pressure value, the cabin temperature value, the air intake temperature value, environmental disturbance monitoring information, and the cabin volume.

[0018] As a preferred embodiment, the interior of the cabin is divided into a test equipment placement area corresponding to the test equipment, an airflow circulation heat exchange area corresponding to the radiator, and an environmental boundary monitoring area.

[0019] The first sensing module includes multiple pressure sensors and temperature sensors respectively disposed in the device under test placement area, the airflow circulation heat exchange area and the environmental boundary monitoring area.

[0020] As a preferred embodiment, the first sensing module calculates the cabin air pressure and cabin temperature values ​​by weighting the output values ​​of the corresponding air pressure sensor and temperature sensor in the device under test placement area, airflow circulation heat exchange area and environmental boundary monitoring area, respectively.

[0021] As a preferred option, an air circulation system installed inside the cabin is also included.

[0022] As a preferred embodiment, the control unit further includes a temperature equalization module;

[0023] The temperature equalization module outputs a power control signal based on the output values ​​of the temperature sensors corresponding to the device under test, the airflow circulation heat exchange zone, and the environmental boundary monitoring zone, in order to adjust the operating power of the air circulation device.

[0024] As a preferred embodiment, the air intake unit includes a precooling box, an air intake valve disposed at the air intake of the precooling box, and a coolant auxiliary pipeline connecting the refrigeration equipment and the precooling box.

[0025] The first sensing module includes a temperature sensor located at the air outlet of the precooling box to obtain the air inlet temperature.

[0026] As a preferred embodiment, the air pressure regulation module also outputs a pre-cooling control signal based on the intake regulation amount of the intake unit to regulate the flow rate of the coolant secondary pipeline.

[0027] As a preferred embodiment, the sensor unit also includes a carbon dioxide concentration sensor installed inside the cabin;

[0028] The air pressure regulation module also outputs an air pressure control signal based on the output value of the carbon dioxide concentration sensor to adjust the air intake volume of the air intake unit and the air extraction volume of the air extraction device.

[0029] The beneficial effects of the technical solutions provided in some embodiments of this specification include at least the following:

[0030] 1. By employing a coordinated control architecture of a pressure master loop and a temperature slave loop, the temperature loop receives the output of the pressure loop in real time as a feedforward signal, enabling the system to quickly compensate for temperature disturbances caused by pressure regulation. This significantly reduces the regulation lag phenomenon in traditional independent PID control and accelerates the initial stabilization process of the environment.

[0031] 2. Based on collaborative control and combined with model predictive control algorithms, the system can proactively predict and compensate for temperature disturbances caused by air pressure regulation, changing from post-correction to pre-intervention, thereby shortening the time for the cabin environment to reach the set value and effectively avoiding overshoot and continuous oscillation, thus improving the speed and stability of environmental control.

[0032] 3. By dividing the interior of the modular cabin into different functional areas and deploying multiple sensors, and by adopting a partition weighting and data fusion algorithm, a comprehensive feedback value that more accurately represents the overall environmental status is generated. This overcomes the impact of uneven distribution of environmental parameters in a large space and improves the environmental perception capability and the accuracy of feedback.

[0033] 4. The control logic of the two sets of coolant valves for intake pre-cooling and cabin constant temperature is decoupled to achieve the two goals of quickly offsetting intake disturbances and precisely maintaining cabin steady state. This allows the two to be adjusted independently and precisely while producing a synergistic effect, improving cooling efficiency while ensuring high precision in final temperature control.

[0034] 5. By integrating safety sensors such as carbon dioxide, the system can automatically start forced ventilation to ensure air quality while maintaining stable air pressure, effectively preventing the risk of oxygen deficiency in the cabin due to equipment operation, and realizing the integration of environmental control and safety assurance. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0036] Figure 1 This is a structural schematic diagram of an environmental simulation cabin testing system provided in the embodiments of this specification.

[0037] Figure 2 This is a schematic diagram of the control unit in an environmental simulation cabin testing system provided in the embodiments of this specification. Detailed Implementation

[0038] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings.

[0039] The terms "first," "second," "third," etc., in the description, claims, and accompanying drawings are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0040] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the described elements without departing from the scope of this specification. Various processes or components may be appropriately omitted, substituted, or added to the examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into other examples.

[0041] Key performance parameters of industrial equipment such as air compressors and hydraulic pump stations (e.g., exhaust efficiency of air compressors, volumetric efficiency of hydraulic pumps, and output power of engines) can change with fluctuations in environmental conditions such as intake air temperature and pressure. Therefore, performance testing of such equipment typically requires placing it in a pre-defined, stable environment and conducting continuous operational evaluations over a considerable period. Environmental simulation chambers are devices designed to provide such controlled and stable testing environments. They isolate the equipment under test from the external environment and accurately simulate target temperature and pressure conditions within the chamber.

[0042] The effectiveness of this testing method depends on the quality of control of the modular testing environment. The modular testing environment must be able to quickly establish itself to improve testing efficiency and maintain high-precision, long-term environmental stability under equipment operation and external interference to ensure the reliability and accuracy of test data. However, due to the coupling effect between temperature and air pressure inside the chamber, traditional independent control methods often exhibit slow response and overshoot oscillations, making it difficult to meet the above requirements.

[0043] Therefore, this application is submitted.

[0044] Reference Figure 1 , Figure 2 As shown, an environmental simulation cabin testing system includes an operating table and a cabin that houses the equipment under test. It also includes a refrigeration device installed outside the cabin, a radiator installed inside the cabin, a coolant pipeline connecting the refrigeration device and the radiator, an air extraction device for extracting air from the cabin, an air intake unit for controlling the air intake volume, a sensor unit, and a control unit.

[0045] The sensor unit includes a first sensing module for acquiring inlet air temperature, cabin temperature and cabin air pressure, and a second sensing module for acquiring performance test data of the device under test.

[0046] The control unit includes a pressure regulation module and a temperature regulation module;

[0047] The air pressure regulation module outputs an air pressure control signal based on the air pressure stability target and the cabin air pressure value to regulate the air intake of the air intake unit and the air extraction of the air extraction equipment.

[0048] The temperature regulation module outputs a temperature control signal based on the temperature stability target, the cabin temperature value, the intake air temperature value, and the air pressure control signal output by the air pressure regulation module, in order to regulate the flow rate of the coolant pipeline.

[0049] Explanatoryly, the environmental simulation cabin testing system proposed in this embodiment is a highly integrated testing platform designed to provide the device under test with a precisely controllable simulated environment in terms of air pressure and temperature for performance testing. For ease of description and understanding, this embodiment uses an air compressor as the device under test in its explanation.

[0050] The system's hardware structure mainly includes the following parts: a container housing the equipment under test; refrigeration equipment located outside the container to provide a cold source for the system; a radiator located inside the container to exchange cooling energy into the container; and coolant piping connecting the refrigeration equipment and the radiator, together forming a physical loop for temperature regulation. Simultaneously, the system is equipped with an air extraction device and an air intake unit to control the total gas volume inside the container, thereby controlling the air pressure inside the container by adjusting the gas flow rates in and out of the container. The sensor unit is responsible for comprehensively collecting system status data. Its first sensor module acquires environmental parameters, including inlet air temperature, container temperature, and container air pressure; its second sensor module is specifically used to collect performance test data of the equipment under test (such as exhaust pressure and exhaust flow rate) to determine the performance of the air compressor under the target test environment. The control panel is the human-machine interface and data processing decision-making center of this system. The industrial control computer (HMI) within it serves as the interface for monitoring and parameter setting. It typically integrates hardware such as an industrial touchscreen, emergency stop switch, control buttons, and status indicator lights for direct operator interaction. It can remotely control the engine of the device under test (DUT), adjust engine speed, and control the DUT's operating status. The PLC main controller is responsible for data acquisition, logic operations, and control output for the cabin, the DUT, and internal and external equipment. In this solution, it is represented as the control unit, which is essentially the control program and algorithm logic. The control unit receives sensor signals and uses two control logic modules—pressure regulation and temperature regulation—to regulate the cabin's environmental conditions (cabin temperature and pressure), outputting pressure and temperature control signals to drive actuators such as fans and valves.

[0051] Specifically, the air pressure regulation module forms an independent closed-loop control loop. It receives the user-set air pressure stability target and compares it with the cabin air pressure value fed back in real time by the first sensing module. After calculation through a control algorithm (such as PID control), it outputs an air pressure control signal. This signal synchronously adjusts the air intake volume of the intake unit (e.g., controlling the opening of the intake damper) and the air extraction volume of the extraction equipment (e.g., controlling the speed of the extraction fan). By dynamically balancing the intake and exhaust flow rates, the cabin air pressure is quickly stabilized at the target value. The temperature regulation module itself also forms a closed-loop control loop. Its setpoint is the user-given temperature stability target, and its feedback value is the cabin temperature value measured by the first sensing module. However, in this invention, the control logic of the temperature regulation module also receives the air pressure control signal and intake air temperature value output in real time from the air pressure regulation module, and senses the strength of external thermal disturbances. Air pressure regulation acts as the master loop, and temperature regulation acts as the slave loop, forming a master-slave coordinated control relationship.

[0052] The collaborative working principle is as follows: When the system needs to adjust the air pressure (e.g., to increase the air pressure), the air pressure regulation module calculates and outputs a control signal (e.g., increasing the opening of the air intake damper). In traditional independent control, the temperature regulation module must wait for a large amount of air at different temperatures to enter the cabin and for the temperature sensor to actually detect the change before it can start operating, resulting in significant lag. In this embodiment, while the air pressure regulation module outputs the control signal, it also sends this signal as a feedforward compensation signal characterizing a known impending disturbance to the temperature regulation module. The temperature regulation module's control algorithm (e.g., PID) performs conventional feedback control based on the deviation between the temperature target and the feedback; on the other hand, based on the received feedforward signal, it calculates the feedforward compensation amount required to offset the temperature rise / fall that may be caused by the current air pressure regulation through a preset correlation (e.g., a feedforward coefficient based on engineering experience or experimental calibration, representing the theoretical temperature rise caused by a unit air pressure regulation). Finally, the temperature control signal output by the temperature regulation module is the superposition of the feedback control amount and the feedforward compensation amount. This signal is used to adjust the flow rate of the coolant pipeline (e.g., to control the opening of the coolant proportional valve), thereby changing the cooling power and affecting the cabin temperature.

[0053] Through the above mechanism, when the pressure regulation action may cause temperature disturbance, the temperature regulation module can adjust the cooling power in advance to suppress it without waiting for the disturbance to actually occur. This achieves dynamic synchronous compensation of temperature for the pressure regulation process, reduces regulation lag, overshoot and oscillation caused by dual-loop coupling, and can significantly shorten the time for the temperature and pressure environment in the chamber to reach and stabilize at the set target value, thereby improving testing efficiency and control quality.

[0054] In addition, the dynamic pressure control method of continuously drawing in and drawing out air can effectively promote the overall circulation and renewal of air in the cabin. It can prevent insufficient oxygen concentration in the cabin due to the continuous operation of the engine of the tested air compressor and the consumption of oxygen in the cabin, thereby ensuring the normal combustion of engine fuel and preventing the danger caused by excessive carbon dioxide concentration when operators enter the cabin.

[0055] In one embodiment of this specification, the control unit further includes a temperature-pressure coupling module;

[0056] The temperature and pressure coupling module includes a temperature and pressure dynamic coupling model constructed based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the air pressure value inside the cabin, the air temperature value inside the cabin, the air intake temperature value, and the cabin volume; the temperature and pressure dynamic coupling model is solved, with the air pressure stability target and the temperature stability target as the constraint minimization objective function, to obtain the temperature and pressure control input sequence and its corresponding temperature and pressure change trajectory within a preset time length in the future;

[0057] The air pressure regulation module outputs an air pressure control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module and the air pressure value inside the cabin;

[0058] The temperature control module outputs a temperature control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module, the intake air temperature value, and the air pressure control signal output by the air pressure control module.

[0059] This embodiment, based on the master-slave collaborative PID, further introduces the temperature-pressure coupled operating condition model predictive control algorithm (MPC), which limits the control unit to adopt a two-level architecture of "MPC+PID". It predicts the mutual coupling effect of air pressure regulation and temperature change in advance, realizing proactive adjustment in advance rather than passive correction afterward, fundamentally solving the response lag problem caused by system inertia in traditional feedback control.

[0060] Illustratively, the control unit also includes a temperature-pressure coupling module for model predictive control. The core of this module is a dynamic temperature-pressure coupling model, a set of mathematical equations based on the laws of conservation of mass and energy that describes the changes in cabin pressure (P) and temperature (T) over time. This model correlates several key physical quantities of the system. For example, the dynamic temperature-pressure coupling model is as follows:

[0061] ,

[0062] ;

[0063] The input variables of this model include an adjustable control input u, which is the intake volume m of the intake unit per unit time. in The air extraction capacity (m) of the air extraction equipment out The heat power Q carried away by the flow rate of the coolant pipeline cool=-η*U Valve *△T, η is the refrigeration and heat exchange efficiency, U Valve This refers to the opening command of the coolant line flow valve, where △T is the average temperature difference between the coolant and the cabin air; real-time measured system status, such as cabin air pressure P, cabin temperature T, and intake air temperature T0. in ; and inherent system parameters, such as the volume V of the container. R is the gas constant of air (approximately 287 J / (kg·K)); ρ is the air density inside the container, which can be obtained from P / (R*T); c p It is the specific heat capacity of air at constant pressure (approximately 1005 J / (kg·K)).

[0064] MPC transforms continuous differential equations into discrete difference equations:

[0065] ,

[0066] This is to enable iterative prediction.

[0067] For explanatory purposes, assume that at time k, the current state is P(k) = 80000 Pa, T(k) = 298.15 K (25℃), and the current control input is m. in (k) = 0.1 kg / s, m out (k) = 0.05 kg / s, T in (k) = 303.15 K (30℃), Q cool (k) = -2000W. Fixed parameters: V = 10m³, R = 287, c p =1005, ρ=P(k) / (R*T(k))≈0.935kg / m³. Control period Δt=1s.

[0068] MPC predicts the next pressure level:

[0069] P(k+1)=80000+1*[(287*298.15 / 10)*(0.1-0.05)]≈80000+428≈80428Pa.

[0070] Predicting the next temperature:

[0071] T(k+1)=298.15+1*[(1 / (0.935*1005*10))*(0.1*1005*(303.15-298.15)+(-2000))]≈298.15-0.159≈297.99K(24.84℃).

[0072] Through these two coupled state equations, MPC can quantitatively predict forward the state of a given control action (m). in mout Q cool Under the given conditions, how will the system state (P, T) evolve? Simulating the system state over Np (prediction time domain) future steps requires assuming a set of future temperature and pressure control input sequences U(k) = {u(k), u(k+1), ..., u(k+Nc−1)}, including the planned values ​​of the intake volume of the intake unit, the extraction volume of the extraction equipment, and the coolant pipeline flow rate, where Nc is the control time domain. The task of the MPC optimization algorithm is to find, among countless possible future control sequences, the set of temperature and pressure control input sequences that enables the predicted trajectory to reach the target most smoothly, quickly, and energy-efficiently, and to use its first term as the current optimal control output.

[0073] The objective function J of this model is:

[0074] .

[0075] The first term is the tracking error term, which calculates the predicted state x(k+i) and the reference trajectory x. ref The deviation between (k+i), x ref The system sets trajectory points (including P and T) for the dynamic temperature and pressure to be achieved by the system in each control cycle. The endpoint of the trajectory is the user-defined final temperature and pressure target (stable air pressure target, stable temperature target). The second term is the control increment change term, which calculates the rate of change of the control quantity Δu=u(k)−u(k−1) to smooth the control action, prevent frequent and large-amplitude movements of valves and fans, and improve equipment life and system stability. The third term is the control cost term, which calculates the deviation of the control quantity itself from a certain reference value (such as zero or the economic operating point) to minimize energy consumption. Q, R, and S are the weighting matrices corresponding to each term. The priority of system control can be specified by adjusting the weights corresponding to air pressure and temperature in Q.

[0076] It is easy to understand that solving the constraints of temperature and pressure dynamic coupling also includes the physical limits of the system, such as the maximum air volume of the fan and the maximum opening of the valve.

[0077] Explanatory, the temperature and pressure control input sequence U(k) and dynamic temperature and pressure setpoint trajectory x obtained by minimizing the objective function. refInstead of directly executing the first control value of the temperature and pressure control input sequence, the air pressure regulation module and the temperature regulation module sequentially apply PID control to the first trajectory point of the dynamic temperature and pressure setpoint trajectory based on this optimization result. The core advantage of MPC lies in its rolling optimization based on a mathematical model, enabling it to proactively plan a dynamic temperature and pressure setpoint trajectory that allows the system to quickly and smoothly reach its stable target. In the next control cycle, MPC starts with new measurements and solves a new optimization problem, obtaining a new future sequence. However, MPC typically operates over long control cycles, and the mathematical model upon which its optimization relies is difficult to accurately describe complex real-world physical changes, resulting in insufficient response to unmodeled, rapid, and minute disturbances such as sensor noise and airflow turbulence. If the control quantity calculated by MPC is directly executed, any model mismatch or unknown disturbance will cause the actual state to gradually deviate from the optimized trajectory, leading to a decline in control quality.

[0078] Therefore, the air pressure portion of the first trajectory point in the dynamic temperature and pressure change trajectory output by the temperature-pressure coupling module replaces the original fixed air pressure stabilization target in the air pressure regulation module, outputting an air pressure control signal. Similarly, the temperature regulation module replaces the original fixed temperature stabilization target with the temperature portion of the first trajectory point, and still integrates the inlet air temperature value and the air pressure control signal output by the air pressure regulation module as feedforward compensation, outputting a temperature control signal after calculation. This generates control commands with superior overall performance, enabling the cabin environment to reach and maintain the set target faster, more smoothly, and more energy-efficiently, thereby improving the accuracy of environmental simulation and testing efficiency.

[0079] In one embodiment of this specification, the sensor unit further includes a third sensing module connected to the device under test and monitoring the disturbance of the environment inside the cabin in real time.

[0080] The temperature and pressure coupling module includes a dynamic temperature and pressure coupling model based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the cabin air pressure value, the cabin temperature value, the air intake temperature value, environmental disturbance monitoring information, and the cabin volume.

[0081] Since the device under test itself also causes disturbances to the cabin temperature and air pressure, this embodiment further optimizes the system's sensing capability and model prediction accuracy. The input information of the sensor unit and the temperature-pressure dynamic coupling model is expanded, enabling the system to sense and compensate for the active disturbances to the cabin environment caused by the operation of the device under test, thereby achieving higher precision environmental control.

[0082] Explanatoryly, the sensor unit also includes a third sensing module directly connected to the device under test (DUT) for real-time monitoring of direct physical disturbances caused by the DUT to the cabin environment during operation. For example, when the DUT is an air compressor, there are thermal disturbances caused by the air compressor engine and its casing dissipating heat into the surrounding air during operation; pressure disturbances caused by the oxygen consumed by the air compressor engine burning fuel and the amount of air drawn into the cabin by its compressor. By setting sensors to monitor the temperature of the air compressor's casing and radiator, and combining this with its heat dissipation surface area, thermal conductivity, or convective heat transfer coefficient, the heat power dissipated by the equipment into the cabin air during operation can be estimated, providing the control system with environmental disturbance monitoring information inside the cabin.

[0083] The temperature-pressure coupling module constructs a dynamic temperature-pressure coupling model, which adds environmental disturbance monitoring information to its input variables. During the rolling optimization calculation of the Model Predictive Control (MPC) algorithm, its internal mathematical model not only considers control actions such as air intake, extraction, and cooling, the current state inside the cabin, and the external air intake temperature, but also includes real-time information on the heat load and air quality consumption currently caused by the measured equipment within the cabin. When solving for the optimal future control sequence, the MPC optimizer can proactively incorporate these known internal disturbances in advance, thereby planning control commands that can synchronously counteract these disturbances. This makes the system more predictive of environmental changes and the control actions more precise.

[0084] For example, the adjusted temperature-pressure dynamic coupling model is as follows:

[0085] ;

[0086] Among them, Q dist This refers to the disturbance term calculated based on environmental disturbance monitoring information.

[0087] It should be noted that the air extraction equipment draws air from inside the cabin, and the air compressor compresses the air inside the cabin and discharges it directly outside for performance testing. The exhaust from the air compressor's engine is also discharged directly outside the cabin.

[0088] In one embodiment of this specification, the interior of the cabin is divided into a test equipment placement area corresponding to the test equipment, an airflow circulation heat exchange area corresponding to the radiator, and an environmental boundary monitoring area.

[0089] The first sensing module includes multiple pressure sensors and temperature sensors respectively disposed in the device under test placement area, the airflow circulation heat exchange area and the environmental boundary monitoring area.

[0090] Explanatoryly, due to the large internal space of the modular cabin and the potentially uneven distribution of the environmental field, a single measurement point may not accurately and comprehensively reflect the overall environmental state within the cabin, causing subsequent control algorithms to fail. This embodiment clarifies the internal space division of the modular cabin and the specific arrangement of sensors in the first sensing module, providing more reliable and representative environmental perception data for the control algorithm.

[0091] Specifically, the interior of the modular testing facility is logically divided into three zones. The equipment under test (DUT) placement zone is the testing functional area of ​​the facility, specifically used for placing and testing the DUT. The physical environmental parameters of this zone directly determine the testing conditions of the DUT, making it a priority area for environmental control and precise monitoring. The airflow circulation and heat exchange zone mainly refers to the path of airflow organization and circulation within the facility and the vicinity of active heat exchange equipment (i.e., radiators). This zone regulates temperature through heat exchange, and its state reflects the immediate effectiveness of environmental regulation and the dynamics of airflow within the facility. The environmental boundary monitoring zone refers to the inner walls, corners, or other boundary areas far from the core equipment and main airflow of the facility, used to indicate whether environmental parameters are uniformly diffused throughout the entire facility.

[0092] Accordingly, the multiple pressure and temperature sensors included in the first sensing module are respectively located in the area where the device under test is placed, the airflow circulation heat exchange area, and the environmental boundary monitoring area. This distributed, zoned sensor network constructs a three-dimensional environmental monitoring system.

[0093] Illustratively, through this division and arrangement, the system can simultaneously acquire differentiated environmental data from core test points, airflow heat exchange paths, and environmental boundaries, improving the comprehensiveness and reliability of the cabin environmental data, so that the control unit can execute control decisions based on multi-sensor data fusion.

[0094] In one embodiment of this specification, the first sensing module calculates the cabin air pressure and cabin temperature values ​​by weighting the output values ​​of the corresponding air pressure sensor and temperature sensor in the device under test placement area, airflow circulation heat exchange area and environmental boundary monitoring area, respectively.

[0095] To illustrate, due to the differences in environmental characteristics between different areas, using single-point or simple arithmetic averages of sensor output values ​​from multiple similar sensors cannot accurately represent the overall environmental state of the device under test, leading to biases in the control baseline and limited control accuracy. Therefore, based on the functional importance of different areas, differentiated weights can be assigned to sensor data from different areas (e.g., assigning higher weights to sensor data from the area where the device under test is located). Then, using specific fusion algorithms (such as weighted averaging and outlier removal), a more accurate and robust comprehensive air pressure and temperature output value can be calculated to represent the overall environmental state within the cabin. This improves the representativeness and reliability of environmental feedback information, enabling closed-loop control to target the actual operating conditions of the device under test, thereby enhancing the control accuracy and testing effectiveness of the entire environmental simulation cabin testing system.

[0096] In one embodiment of this specification, an air circulation device installed inside the cabin is also included.

[0097] Illustratively, due to differences in cold / hot air density, uneven equipment heating, and localized airflow caused by air intake / exhaust, temperature stratification or regional temperature differences can easily form inside the cabin without forced circulation. The newly added air circulation device in this embodiment is an auxiliary actuator for achieving uniform and stable cabin environmental parameters. It actively breaks the static distribution of air inside the cabin, promoting the formation of controllable airflow organization.

[0098] Specifically, air circulation equipment typically consists of multiple circulating fans or similar devices, scientifically arranged inside the cabin. Its working principle is to continuously agitate the air within the cabin, breaking down temperature stratification and evenly distributing the cooling energy from radiators or the heat generated by the equipment throughout the entire cabin space, especially in the area where the tested equipment is placed, thus promoting temperature uniformity. This ensures that the values ​​monitored by temperature sensors placed in different locations accurately reflect a homogeneous overall environment, providing a reliable data foundation for high-precision closed-loop temperature control.

[0099] Meanwhile, the air circulation system effectively transports cabin air to the surface of the radiator, increasing the contact and heat exchange rate between the air and the radiator, making temperature regulation faster and more effective. Forced air circulation also helps avoid minor differences in local air pressure and accelerates the mixing of gases within the cabin, resulting in a more uniform distribution of gas components, including oxygen and carbon dioxide. Combined with the pressure control method of simultaneous air extraction and intake, this ensures a consistent cabin environment.

[0100] In one embodiment of this specification, the control unit further includes a temperature equalization module;

[0101] The temperature equalization module outputs a power control signal based on the output values ​​of the temperature sensors corresponding to the device under test, the airflow circulation heat exchange zone, and the environmental boundary monitoring zone, in order to adjust the operating power of the air circulation device.

[0102] This embodiment minimizes temperature differences between different areas inside the cabin by intelligently adjusting the operating power of air circulation equipment (such as a circulating fan).

[0103] Specifically, the temperature equalization module receives input signals from temperature sensors located in the equipment under test area, the airflow circulation heat exchange area, and the environmental boundary monitoring area. By acquiring and comparing temperature readings from these three functional areas in real time, the instantaneous temperature distribution within the cabin can be accurately perceived. Based on this real-time temperature distribution information, the temperature equalization module executes a control algorithm (e.g., proportional-integral control based on the maximum temperature difference) and outputs corresponding power control signals (e.g., adjusting the inverter output or directly controlling the fan motor speed). The control objective is to minimize the temperature difference between the three areas. This dynamically and precisely adjusts the operating power of the air circulation equipment.

[0104] For example, when a temperature in a certain area is detected to be significantly higher than that in other areas, the temperature equalization module will increase the power of the air circulation device and speed up the airflow to carry heat from the high-temperature area to the low-temperature area at a faster rate, thus promoting mixing; when the temperature in each area tends to be uniform, the circulation power will be appropriately reduced to save energy.

[0105] In one embodiment of this specification, the air intake unit includes a precooling box, an air intake valve disposed at the air inlet of the precooling box, and a coolant auxiliary pipeline connecting the refrigeration equipment and the precooling box;

[0106] The first sensing module includes a temperature sensor located at the air outlet of the precooling box to obtain the air inlet temperature.

[0107] For illustrative purposes, this embodiment further defines the specific structure of the air intake unit, clarifying the hardware architecture for pre-processing external air. The air intake unit includes a pre-cooling box, an airflow valve (i.e., an actuator for adjusting the airflow) located at the air inlet of the pre-cooling box, and a coolant auxiliary pipeline connecting the refrigeration equipment and the pre-cooling box, forming an independent air intake pre-processing channel. External ambient air first passes through the airflow valve to regulate its flow rate, then enters the pre-cooling box. Inside the pre-cooling box, the low-temperature coolant flowing through the coolant auxiliary pipeline exchanges heat with the incoming air, thus pre-regulating its temperature before it enters the main cabin of the container. This reduces the disturbance of the newly entered external air to the cabin's internal temperature, lowers the impact of temperature-pressure coupling effects, and simplifies the difficulty of regulating and controlling the cabin environment. A temperature sensor located at the air outlet of the pre-cooling box directly measures the real-time intake temperature of the pre-cooled air before it enters the main cabin of the container. This makes it possible to actively intervene and accurately sense the intake air temperature, rather than making it difficult to measure accurately or being directly affected by the external climate, thereby improving the system's ability to resist external temperature fluctuations.

[0108] It's easy to understand that the temperature fluctuations of the pre-cooled intake air significantly reduce their impact on the cabin temperature. In temperature closed-loop control, the magnitude of the feedforward compensation is calculated based on the predicted intake air thermal disturbance. This reduces the dependence of the temperature control loop on feedforward compensation, thus alleviating the regulation pressure on the control system.

[0109] In one embodiment of this specification, the air pressure regulating module further outputs a pre-cooling control signal based on the intake regulating amount of the intake unit to regulate the flow rate of the coolant secondary pipeline.

[0110] This implementation proposes a collaborative control logic for the intake pretreatment process to achieve a high degree of linkage between air pressure regulation and intake precooling.

[0111] Explained, the air pressure regulation module not only outputs air pressure control signals to regulate the air intake valve based on the air pressure stability target and the cabin air pressure value, but also outputs pre-cooling control signals based on the air intake regulation amount of the air intake unit, in order to regulate the flow rate of the coolant auxiliary pipeline connected to the pre-cooling box, thus forming a temperature and pressure coordinated control.

[0112] Its working logic is as follows: When the air pressure regulation module calculates and outputs an intake air regulation amount (such as increasing the opening of the intake air volume valve to increase the cabin pressure), this regulation amount will simultaneously trigger the adjustment of the coolant secondary pipeline flow rate. Based on the magnitude of this intake air regulation amount, and combined with information such as the measured intake air temperature, the precooling amount required to process the increased intake air temperature to the desired value is calculated, and a corresponding precooling control signal is generated (such as controlling the opening of the coolant secondary pipeline flow valve). Changes in intake air volume will drive changes in precooling intensity in real time and feedforward to offset the possible increase in heat load (or cold load) due to the increase in intake air volume, ensuring that the air temperature entering the cabin is as stable as possible.

[0113] This embodiment abandons the traditional design of synchronized and uniformly opening coolant valves in container cooling systems. Instead, it designs two separate coolant flow valves for independent control, addressing two different cooling function requirements: pre-cooling intake air and maintaining a constant temperature inside the container. These valves are tailored to different needs based on adjustment targets, response priorities, and control precision. The secondary coolant flow valve is adjusted to quickly counteract intake air disturbances, while the main coolant flow valve is adjusted to precisely maintain steady-state conditions inside the container.

[0114] Intake pre-cooling serves as an active compensation step in the air pressure regulation process, minimizing temperature disturbances introduced by air pressure regulation at the source and providing a solid foundation for precise temperature stability control within the cabin.

[0115] In one embodiment of this specification, the sensor unit further includes a carbon dioxide concentration sensor disposed inside the cabin;

[0116] The air pressure regulation module also outputs an air pressure control signal based on the output value of the carbon dioxide concentration sensor to adjust the air intake volume of the air intake unit and the air extraction volume of the air extraction device.

[0117] For illustrative purposes, this embodiment adds an environmental safety monitoring and protection function, and introduces an active monitoring and adjustment mechanism for the air quality inside the cabin to prevent the cabin environment from deteriorating due to the operation of the tested equipment, and to ensure the normal operation of the tested equipment and the safety of the operators.

[0118] Specifically, the sensor unit also includes a carbon dioxide concentration sensor installed inside the cabin. This sensor is used to monitor the carbon dioxide concentration in the cabin air in real time and continuously. During the test, when the equipment under test is an air compressor or other equipment driven by an internal combustion engine, the continuous combustion of its engine will consume the oxygen in the cabin, causing the carbon dioxide concentration to gradually accumulate. This poses a potential risk of causing oxygen deficiency in the cabin, affecting the operation of the equipment under test, and threatening the safety of operators (such as when entering the cabin to replace the equipment under test).

[0119] Explaining the implications, the pressure control signal output by the pressure regulation module is based not only on the pressure stability target and the cabin pressure value, but also on the output value of the carbon dioxide concentration sensor. The system can set a safe threshold for the carbon dioxide concentration. When the carbon dioxide concentration detected by the sensor is below this threshold, the system performs precise pressure control according to its original logic. Once the carbon dioxide concentration approaches or exceeds the safe threshold, the pressure regulation module will overlay the original pressure control logic and simultaneously adjust the air intake of the intake unit and the air extraction of the extraction equipment, typically increasing both flow rates simultaneously to enhance circulation, increase the cabin air renewal rate, and thus rapidly dilute and reduce the cabin carbon dioxide concentration until it returns to below a safe level.

[0120] Therefore, the pressure regulation module has the dual functions of pressure closed-loop control and safety concentration closed-loop control, realizing the automation and initiative of the test environment safety assurance, maintaining sufficient oxygen concentration in the chamber, thereby ensuring the continuous and stable operation of the engine combustion process of the tested equipment, and also improving the personnel safety assurance level and reliable operation capability of the entire container test system.

[0121] The embodiments described above are merely preferred embodiments of this specification and are not intended to limit the scope of this specification. Any modifications and improvements made by those skilled in the art to the technical solutions of this specification without departing from the spirit of this specification should fall within the protection scope defined by the claims of this specification.

Claims

1. An environmental simulation cabin testing system, comprising an operating console and a cabin housing the equipment under test, characterized in that, It also includes refrigeration equipment installed outside the cabin, radiators installed inside the cabin, coolant pipelines connecting the refrigeration equipment and the radiators, air extraction equipment for drawing air out of the cabin, air intake unit for controlling the air intake volume, sensor unit, and control unit. The sensor unit includes a first sensing module for acquiring inlet air temperature, cabin temperature and cabin air pressure, and a second sensing module for acquiring performance test data of the device under test. The control unit includes a pressure regulation module and a temperature regulation module; The air pressure regulation module outputs an air pressure control signal based on the air pressure stability target and the cabin air pressure value to regulate the air intake of the air intake unit and the air extraction of the air extraction equipment. The temperature regulation module outputs a temperature control signal based on the temperature stability target, the cabin temperature value, the intake air temperature value, and the air pressure control signal output by the air pressure regulation module, in order to regulate the flow rate of the coolant pipeline.

2. An environmental chamber test system according to claim 1, wherein: The control unit also includes a temperature-pressure coupling module; The temperature-pressure coupling module includes a temperature-pressure dynamic coupling model constructed based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the cabin air pressure value, the cabin temperature value, the air intake temperature value, and the cabin volume; the temperature-pressure dynamic coupling model is solved, with the air pressure stability target and the temperature stability target as the constraint minimization objective function, to obtain the temperature-pressure control input sequence and its corresponding temperature-pressure change trajectory within a future preset time length; The air pressure regulation module outputs an air pressure control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module and the air pressure value inside the cabin; The temperature control module outputs a temperature control signal based on the temperature and pressure change trajectory output by the temperature and pressure coupling module, the intake air temperature value, and the air pressure control signal output by the air pressure control module.

3. An environmental chamber test system according to claim 2, wherein: The sensor unit also includes a third sensing module that is connected to the device under test and monitors the disturbance of the environment inside the cabin in real time. The temperature and pressure coupling module includes a dynamic temperature and pressure coupling model based on the air intake volume of the air intake unit, the air extraction volume of the air extraction equipment, the flow rate of the coolant pipeline, the cabin air pressure value, the cabin temperature value, the air intake temperature value, environmental disturbance monitoring information, and the cabin volume.

4. The environmental chamber test system of claim 1, wherein: The interior of the cabin is divided into a test equipment placement area, an airflow circulation heat exchange area corresponding to the radiator, and an environmental boundary monitoring area. The first sensing module includes multiple pressure sensors and temperature sensors respectively disposed in the device under test placement area, the airflow circulation heat exchange area and the environmental boundary monitoring area.

5. An environmental chamber test system according to claim 4, wherein: The first sensing module calculates the cabin air pressure and cabin temperature values ​​by weighting the output values ​​of the corresponding air pressure sensor and temperature sensor in the device under test placement area, airflow circulation heat exchange area and environmental boundary monitoring area, respectively.

6. An environmental chamber test system according to claim 5, wherein: It also includes air circulation equipment installed inside the cabin.

7. The environmental simulation cabin testing system according to claim 6, characterized in that: The control unit also includes a temperature equalization module; The temperature equalization module outputs a power control signal based on the output values ​​of the temperature sensors corresponding to the device under test, the airflow circulation heat exchange zone, and the environmental boundary monitoring zone, in order to adjust the operating power of the air circulation device.

8. The environmental chamber test system of claim 1, wherein: The air intake unit includes a precooling box, an air intake valve located at the air inlet of the precooling box, and a coolant auxiliary pipeline connecting the refrigeration equipment and the precooling box. The first sensing module includes a temperature sensor located at the air outlet of the precooling box to obtain the air inlet temperature.

9. An environmental test chamber system according to claim 8, wherein: The air pressure regulation module also outputs a pre-cooling control signal based on the intake regulation amount of the intake unit to regulate the flow rate of the coolant secondary pipeline.

10. The environmental chamber test system of claim 1, wherein: The sensor unit also includes a carbon dioxide concentration sensor installed inside the cabin; The air pressure regulation module also outputs an air pressure control signal based on the output value of the carbon dioxide concentration sensor to adjust the air intake volume of the air intake unit and the air extraction volume of the air extraction device.

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