An integrated vacuum pump testing method

Abstract

The present application relates to the technical field of device testing method, and particularly relates to a kind of integrated vacuum pump testing method, comprising the following steps: establishing adsorption saturation state in closed test cavity, including filling mixed gas into test cavity, gradually reducing the temperature of cavity wall of test cavity, so that gas molecules are adsorbed on the inner wall of cavity;Apply sudden load to the vacuum pump to be tested, including starting the vacuum pump while triggering the infrared heating module, so that the temperature of the cavity wall of the test cavity rises to a predetermined temperature at a predetermined heating rate;Collect desorption dynamic parameters to generate desorption characteristic values, including real-time monitoring of gas release during the desorption process, combining desorption time constant and average vacuum, to calculate the release rate of adsorbed gas.The present application improves the accuracy and repeatability of evaluating the weak gas handling performance of the vacuum pump, and is suitable for quality detection and dynamic performance comparison analysis of high-sensitivity vacuum devices.

Description

Technical Field

[0001] This invention relates to the field of equipment testing methods, and in particular to an integrated vacuum pump testing method. Background Technology

[0002] As a key component in high vacuum systems, the vacuum pump's ability to pump out trace amounts of gas directly affects the ultimate vacuum and stable operating performance of the overall system. Existing vacuum pump performance testing methods mainly rely on steady-state pumping speed measurement or ultimate vacuum determination, often ignoring the vacuum pump's response characteristics to weak release sources such as adsorbed gas and condensed moisture, making it difficult to fully reflect its actual pumping capacity under unsteady load conditions.

[0003] In gas adsorption-desorption performance testing, traditional methods typically employ a liquid nitrogen cold trap to cool the wall surface and form an adsorption layer, followed by natural heating to release the adsorbed gas. However, this method suffers from problems such as uncontrollable cooling rate, delayed desorption triggering, uneven temperature distribution, and difficulty in precise process synchronization, leading to significant fluctuations in test results. Furthermore, the lack of high-resolution data acquisition and quantitative indicators during desorption makes it impossible to accurately assess the response behavior of the vacuum pump to transient loads.

[0004] In addition, existing methods generally rely on manual judgment of adsorption equilibrium and the timing of desorption termination, lacking dynamic criteria and statistical validity determination mechanisms, resulting in test procedures that depend on experience and lack reproducibility. Summary of the Invention

[0005] This invention provides an integrated vacuum pump testing method that can accurately characterize the dynamic performance of a vacuum pump in a controlled adsorption environment through spatiotemporal co-loading and real-time data analysis.

[0006] An integrated vacuum pump testing method includes the following steps:

[0007] S1, establishing an adsorption saturation state in a closed test chamber, including filling the test chamber with a mixed gas and controlling the chamber wall temperature to gradually decrease so that gas molecules are adsorbed on the inner wall of the chamber.

[0008] S2, apply a sudden load to the vacuum pump under test, including starting the vacuum pump and triggering the infrared heating module at the same time, so that the temperature of the test chamber wall rises to the predetermined temperature at a predetermined heating rate;

[0009] S3, collect dynamic parameters of desorption to generate desorption characteristic values, including real-time monitoring of gas release during the desorption process, and calculate the adsorbed gas release rate η by combining the desorption time constant and average vacuum degree.

[0010] Optionally, S1 specifically includes:

[0011] S11, a mixture of nitrogen and water vapor with a volume ratio of 3:1 is introduced into the sealed test chamber through a multi-channel gas distribution system to control the gas pressure within a preset range;

[0012] S12, activate the semiconductor cooling module to reduce the temperature of the inner wall of the cavity from room temperature to -35°C at a step rate and maintain the current temperature;

[0013] S13, when the fluctuation range of the cavity vacuum monitoring value is less than the predetermined fluctuation threshold, it is determined that the adsorption saturation state has been reached.

[0014] Optionally, the fluctuation range of the vacuum monitoring value in S13 is calculated as follows:

[0015] in, P(t) represents the change in vacuum level per unit time, where P(t) is the vacuum level reading of the cavity at time t, and 10 min is the time window.

[0016] The predetermined fluctuation threshold is set to 0.15 kPa / 10 min;

[0017] When the fluctuation range of the cavity vacuum level monitoring value per unit time meets the following conditions:

[0018] Furthermore, if this condition is met three times consecutively, it is determined that the test chamber has reached the adsorption saturation state. "Meeting three times consecutively" means that the fluctuation condition is less than 0.15 kPa in at least three adjacent time windows.

[0019] Optionally, the multi-channel gas distribution system is used to fill the sealed test chamber with a mixed gas composed of nitrogen and water vapor, specifically including:

[0020] Nitrogen channel: includes nitrogen gas source and mass flow meter;

[0021] Water vapor channel: includes an ultrasonic atomizing water vapor generator and an atomization rate control valve, wherein the atomization rate control valve adjusts the atomization flow rate according to the target output ratio;

[0022] Gas mixing chamber: The nitrogen gas and water vapor are fully mixed in the gas mixing chamber, which is equipped with a stainless steel tubular static mixer.

[0023] Proportional feedback control module: Real-time acquisition of flow information and chamber pressure data of nitrogen and water vapor channels; Adjustment of mass flow meter and atomization rate control valve through proportional-integral-derivative algorithm in main controller to ensure that the volume ratio of mixed gas is controlled at 3:1.

[0024] Optionally, S2 specifically includes:

[0025] S21, while sending a start signal to the vacuum pump under test, triggers the ring-shaped distributed infrared heating module;

[0026] S22, through infrared radiation of a preset wavelength, causes the temperature of the inner wall of the test chamber to rise from -35℃ to 65℃ at a rate of 12-15℃ / s.

[0027] S23 uses a thermocouple array to collect real-time data on the test chamber wall and calculates the temperature gradient of the test chamber wall. When the maximum local temperature difference reaches the maximum temperature threshold, the compensation heater is activated to perform temperature equalization control.

[0028] Optionally, the infrared heating module employs multiple sets of infrared heaters arranged in a ring, with a radiation wavelength covering 2.5–4.0 μm.

[0029] Optionally, the maximum local temperature difference is calculated as: ΔT max =max(T) i )-min(T i ),i=1,2,...,16; when ΔT max When the temperature exceeds 8℃, the zone compensation heater is activated, and the compensation power is dynamically adjusted according to the temperature difference in each zone.

[0030]

[0031] Among them, T i Let i be the temperature value measured by the i-th thermocouple. The average temperature at the current 16 points, ΔT max This represents the maximum temperature difference in the real-time temperature distribution of the cavity wall. This represents the output power of the compensation heater in region i.

[0032] Optionally, S3 specifically includes:

[0033] S31, the amount of gas released during the desorption process ΔQ is monitored in real time by a quadrupole mass spectrometer;

[0034] S32, a capacitive thin-film vacuum gauge is used to record the vacuum degree change curve, and the desorption time t corresponding to the time constant τ is extracted;

[0035] S33, Calculate the average vacuum level P m ;

[0036] S34, output the adsorbed gas release rate according to the formula for adsorbed gas release rate. The data is considered valid when the standard deviation of the η value is less than the data validity standard deviation threshold after multiple consecutive calculations.

[0037] Optionally, the gas release amount ΔQ is calculated as follows:

[0038]

[0039] Where k is the cavity volume calibration coefficient, A i Let A be the peak area corresponding to mass number 18 in the i-th sampling. bas denoted as the baseline area of ​​the mass channel, and n as the number of samplings during the desorption process.

[0040] Optionally, the formula for calculating the adsorbed gas release rate is as follows:

[0041] The beneficial effects of this invention are:

[0042] This invention provides a vacuum pump testing method that can form a stable adsorption layer under controlled low-temperature conditions. Gas desorption is induced by high-energy infrared rapid heating and simultaneous loading with a vacuum pump. Combined with dynamic acquisition via dual-channel mass spectrometry and vacuum level, key characteristic parameters such as desorption release rate are extracted. This method has advantages such as fast heating response, good temperature field uniformity, high accuracy in gas release detection, and clear quantification of characteristic criteria. It improves the accuracy and repeatability of evaluating the weak gas handling performance of vacuum pumps and is suitable for quality testing and dynamic performance comparison analysis of high-sensitivity vacuum devices.

[0043] This invention uses a multi-channel gas distribution system to precisely fill a sealed test chamber with a nitrogen-to-water vapor mixture in a volume ratio of 3:1. A semiconductor refrigeration module is used to lower the chamber wall temperature in a stepped temperature control manner to form a stable adsorption saturation layer. At the same time, the vacuum fluctuation threshold is used as a criterion to dynamically determine whether the adsorption has reached a steady state. This invention overcomes the indeterministic problem of traditional methods that rely on fixed time for judgment, ensuring that the subsequent desorption process starts at the same point and that the data has good repeatability.

[0044] This invention employs a ring-shaped distribution of infrared heating modules, which are synchronously triggered at the moment the vacuum pump starts. The cavity wall is rapidly heated with infrared radiation of a predetermined wavelength, optimizing the excitation of ice crystal desorption kinetics. Combined with a thermocouple array to construct a temperature field monitoring network, when a local temperature difference is detected to be greater than the temperature threshold, the zone compensation heater is automatically activated to achieve active temperature uniformity control, significantly reducing phenomena such as desorption lag and local saturation shift caused by uneven temperature field.

[0045] This invention uses a capacitive thin-film vacuum gauge to extract the time point corresponding to the vacuum response time constant τ as the desorption duration t. At the same time, it integrates a quadrupole mass spectrometer to collect the gas release amount ΔQ at high frequency and calculates the average vacuum degree P by integration, outputting the desorption characteristic parameter η. To ensure the reliability of the results, the standard deviation of the η value in three independent experiments is used as the validity threshold to construct a multi-index fusion system for evaluating desorption performance, which improves the quantitative capability and data stability of the testing system. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in this 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 for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of the testing method flow according to an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of the formation of a mixed gas according to an embodiment of the present invention. Detailed Implementation

[0049] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. For some well-known technologies, those skilled in the art may also use other alternative methods to implement the invention. Moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0050] like Figures 1-2 As shown, an integrated vacuum pump testing method includes the following steps:

[0051] S1, establishing an adsorption saturation state in a closed test chamber, including filling the test chamber with a mixed gas and controlling the chamber wall temperature to gradually decrease so that gas molecules are adsorbed on the inner wall of the chamber.

[0052] S2, apply a sudden load to the vacuum pump under test, including starting the vacuum pump and triggering the infrared heating module at the same time, so that the temperature of the test chamber wall rises to the predetermined temperature at a predetermined heating rate;

[0053] S3 collects dynamic parameters of desorption to generate desorption characteristic values ​​(release rate), including real-time monitoring of the gas release during the desorption process. Combined with the desorption time constant and average vacuum degree, the adsorbed gas release rate η is calculated. The value of η essentially characterizes the rate of adsorbed gas release per unit vacuum pressure; a larger value indicates stronger adsorption on the material surface and weaker anti-interference capability of the vacuum pump.

[0054] The sealed test chamber is a simulated working environment chamber independent of the vacuum pump under test. It is specifically designed to simulate the gas adsorption-desorption environment of the vacuum pump in actual operation. It is sealed to the air inlet of the vacuum pump under test through a flange interface. The mixed gas injection and infrared heating module both act on the sealed test chamber.

[0055] The integrated testing method of this invention integrates the construction of the adsorption environment, the application of sudden load, the control of infrared heating, the synchronous acquisition of vacuum degree and gas release, the calculation of characteristic parameters and the determination of data validity into the same closed-loop testing process. The various parts are linked and coordinated with each other, avoiding the problems of being scattered, relying on multiple sets of devices and manual judgment in traditional testing, and realizing the integration of the structure and function of the testing system.

[0056] S1 specifically includes:

[0057] S11, a nitrogen-water vapor mixture with a volume ratio of 3:1 is introduced into the sealed test chamber through a multi-channel gas distribution system, and the total gas pressure P is controlled. g It stabilizes in the 50kPa-80kPa range.

[0058] S12, activate the semiconductor cooling module to control the temperature T inside the cavity wall. wall It is cooled from room temperature to -35°C at a rate of ≤5°C / min.

[0059] S13, Real-time monitoring of cavity vacuum degree P(t), when the change in vacuum degree per unit time meets the following condition:

[0060] Furthermore, if this condition is met three times consecutively, the test chamber is determined to have reached adsorption saturation.

[0061] Among them, P g T is the stable pressure of the gas mixture within the cavity. wall To test the temperature of the inner wall of the cavity, P(t) is the vacuum reading of the cavity at time t. The value represents the change in vacuum level per unit time; "three consecutive times" means that the above fluctuation conditions are all less than 0.15 kPa in at least three adjacent time windows (10 minutes each).

[0062] The multi-channel gas distribution system is used to precisely fill a sealed test chamber with a mixture of nitrogen and water vapor, specifically including the following:

[0063] Nitrogen channel: includes a high-purity nitrogen source and a mass flow meter. The nitrogen source provides high-purity nitrogen; the mass flow meter is used to accurately adjust and monitor the nitrogen flow rate in real time. It has a digital control interface and can interact with the main control system for data exchange and closed-loop feedback control.

[0064] Water vapor channel: includes an ultrasonic atomizing water vapor generator and an atomization rate control valve. The water vapor generator operates at a frequency of 1.7MHz and is used to atomize deionized water into water vapor with a particle size of less than 5μm. The atomization rate control valve adjusts the atomization flow rate according to the target output ratio. The control valve communicates with the main control system and adjusts the atomization intensity by adjusting the water supply rate and the drive frequency.

[0065] Gas mixing chamber: Nitrogen and water vapor are thoroughly mixed in the gas mixing chamber, which uses a stainless steel tubular static mixer.

[0066] The proportional feedback control module includes a gas proportional acquisition module, a main controller, and a feedback adjustment unit. It collects flow information and chamber pressure data of nitrogen and water vapor channels in real time. The MFC and atomization rate control valve are adjusted through the proportional-integral-derivative (PID) algorithm in the main controller to ensure that the mixed gas volume ratio is stably controlled at 3:1. When the mixing ratio or chamber pressure deviates from the set value, the output of each channel is automatically corrected to achieve dynamic closed-loop control.

[0067] The following is a specific scheme for how the PID control algorithm in a proportional feedback control system adjusts the mass flow meter (MFC) and the atomization rate control valve to maintain a stable volume ratio of nitrogen to water vapor mixture at 3:1:

[0068] I. Control Target: Let the target volume ratio be: in, The real-time volumetric flow rate of the nitrogen channel is measured by the MFC. The equivalent volumetric flow rate of the water vapor channel is estimated by the atomization rate control valve.

[0069] II. Definition of Error:

[0070] The real-time mixing ratio is:

[0071] The error is defined as: e(t) = R target -R(t);

[0072] III. PID Control Formula

[0073] The regulation signal u(t) from the MFC output or the atomizing valve input to the PID controller is calculated as follows:

[0074]

[0075] Among them, K p K is the proportional gain, used to adjust the system response speed. i For integral gain, to eliminate steady-state error, K d The differential gain is used to suppress error oscillations, and u(t) is the control output signal that can be used for adjustment.

[0076] Nitrogen MFC opening (if water vapor flow rate is stable);

[0077] Or the atomization rate control valve's drive frequency / water supply rate (if nitrogen flow rate is the reference).

[0078] IV. Application Logic:

[0079] Real-time data collection and

[0080] Calculate the actual mixing ratio R(t) and the error e(t);

[0081] The error is input into the PID controller to generate the adjustment signal u(t);

[0082] The controller outputs a new setpoint to the MFC and / or atomizing valve based on the adjustment strategy.

[0083] The control cycle is typically set to 0.5 to 1.0 seconds to ensure dynamic stability of the mixing ratio.

[0084] The semiconductor cooling module is used to reduce the temperature of the inner wall of a sealed test chamber from room temperature to -35°C at a controlled rate, achieving a controllable step-cooling process to promote the uniform formation of the adsorption layer. It mainly includes the following components:

[0085] 1. Thermoelectric cooler: including multi-stage Peltier plate array, preferably a five-stage low-temperature cascade type (LairdCP5-127 series or equivalent custom device);

[0086] 2. Temperature control drive circuit module: A closed-loop constant current driver composed of a PWM modulation chip and a high-power MOSFET receives temperature setting commands from the main control system, adjusts the operating voltage of the thermoelectric cooler in real time, and realizes step-by-step temperature control rate setting.

[0087] 3. Temperature sensing and feedback: The sensor type is PT1000 thin film thermistor, which is installed at the four corners and bottom of the cavity to form a temperature sampling matrix, realize closed-loop temperature control and temperature gradient monitoring, ensure accurate segmentation of temperature drop rate, and meet the requirements of ice crystal control and adsorption layering.

[0088] 4. Heat dissipation system:

[0089] Hot-end cooling method: liquid cooling circulation system + high-efficiency heat exchanger, or forced air cooling fin assembly;

[0090] Liquid cooling configuration: microchannel cold plate + coolant pump + heat exchanger;

[0091] Maintain stable heat dissipation at the hot end of the thermoelectric cooler to prevent heat buildup from causing performance degradation at the cold end.

[0092] S2 specifically includes:

[0093] S21, at the same time the vacuum pump under test is started, a synchronous trigger signal is sent to the ring-shaped infrared heating module, triggering the infrared heating module to emit infrared radiation with a wavelength of 2.5-4μm.

[0094] S22, using infrared radiation heating to raise the temperature T of the inner wall of the test chamber. wall (t) at a rate: The temperature is increased from an initial temperature of -35°C to 65°C, with the heating phase including the ice crystal phase transition range.

[0095] S23, by real-time acquisition of temperature distribution through a 16-point thermocouple array installed on the inner wall of the cavity, the maximum local temperature difference is calculated: ΔT max =max(T) i )-min(T i ),i=1,2,...,16; when ΔT max When the temperature exceeds 8℃, the zone compensation heater is activated, and the compensation power is dynamically adjusted according to the temperature difference in each zone.

[0096]

[0097] T wall (t) represents the temperature of the inner wall of the cavity at a certain moment. T represents the rate of temperature increase of the cavity wall. i Let i be the temperature value measured by the i-th thermocouple. The average temperature at the current 16 points, ΔT max This represents the maximum temperature difference in the real-time temperature distribution of the cavity wall. This represents the output power of the compensation heater in region i.

[0098] The "ice crystal phase transition range" refers to the temperature range within which ice crystals transform from a solid to a liquid state (i.e., melt) during a temperature increase. Within this range, the substance undergoes a phase transition process, characterized by the fact that although the temperature continues to rise, the energy is mainly used to destroy the ice crystal structure (overcoming the lattice binding energy) rather than to cause the temperature to rise rapidly. For solid systems containing adsorbed water molecules (ice layers or microcrystalline water adsorbed on the cavity walls), this process is usually accompanied by structural loosening and enhanced water desorption. In a vacuum testing chamber, this stage is the critical temperature range where desorption behavior is most active.

[0099] The infrared heating module uses six sets of silicon carbide radiators arranged in a ring, with a single set power of 2.4kW and a radiation wavelength coverage of 2.5–4.0μm;

[0100] Energy spectrum distribution:

[0101] 2.5–3.0 μm: accounting for 45%, used to excite surface adsorption of water molecules;

[0102] 3.0–3.5 μm: accounting for 38%, used to penetrate the ice crystal layer and promote desorption;

[0103] 3.5–4.0 μm: accounting for 17%, used to maintain substrate temperature.

[0104] S3 specifically includes:

[0105] S31, using a quadrupole mass spectrometer to monitor the gas release ΔQ during the desorption process in real time, with a sampling frequency of not less than 100Hz, and calculating the release amount through digital integration:

[0106]

[0107] Where k is the cavity volume calibration coefficient (if the cavity is 5L, k = 0.078), A i The mass number corresponding to the i-th sample The peak area, A base The baseline area of ​​the mass channel is denoted as n, and the number of samplings during the desorption process is denoted as n.

[0108] S32, a capacitive thin-film vacuum gauge is used to record the vacuum degree change curve, and the desorption time t corresponding to the characteristic time constant τ is extracted, where τ is defined as:

[0109] τ=twhenP(t)=P0-0.632·(P0-P e );

[0110] Where P0 is the initial vacuum level (Pa) at the moment of heating start-up, P e For the stable value of vacuum degree, when The vacuum degree at that moment is taken as P(t), which is the vacuum degree reading at time t, and τ is the time constant of the system vacuum response, which is actually used to define the desorption time.

[0111] "0.632" is a standard mathematical constant derived from the first-order exponential decay model. It is used to describe the vacuum desorption process and reflects the definition of the characteristic time constant τ in desorption kinetics. In physical systems (including vacuum, temperature, pressure, etc.), the dynamic response of a first-order system can be described in the following exponential form: P(t) = P e +(P0-P e )·e -t / τ When t = τ, the above equation becomes:

[0112] P(τ)=P e +(P0-P e )·e -1 =P e +(P0-P e 0.368;

[0113] Therefore: P(τ)=P0-0.632·(P0-P e This means that when the system changes from P0 to P... eThe time taken to reach 63.2% of the total change during the process is defined as the time constant τ.

[0114] S33, Calculate the average vacuum level P m The integral average method is defined as follows:

[0115] Where t is the desorption time extracted from τ, and P(τ) is the function of vacuum degree changing with time in the time interval [0, t].

[0116] S34, the adsorbed gas release rate η is output according to the following formula:

[0117] Furthermore, when the standard deviation σ of the η value is calculated from three consecutive trials... η If the value is less than 0.02, the data set is considered valid.

[0118]

[0119] Where, η i Let i be the adsorbed gas release rate calculated in the i-th time. N represents the average of three calculations. u This is the number of sampling rounds in the validity criterion, with a default value of 3. 0.02 is the standard deviation threshold for data validity.

[0120] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0121] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An integrated vacuum pump testing method, characterized in that, Includes the following steps: S1, establishing an adsorption saturation state in a closed test chamber, including filling the test chamber with a mixed gas and controlling the chamber wall temperature to gradually decrease so that gas molecules are adsorbed on the inner wall of the chamber. S2, apply a sudden load to the vacuum pump under test, including starting the vacuum pump and triggering the infrared heating module at the same time, so that the temperature of the test chamber wall rises to the predetermined temperature at a predetermined heating rate; S3, collect desorption dynamic parameters to generate desorption characteristic values, including real-time monitoring of gas release during the desorption process, and calculate the adsorbed gas release rate by combining the desorption time constant and average vacuum degree; S1 specifically includes: S11, a mixture of nitrogen and water vapor with a volume ratio of 3:1 is introduced into the sealed test chamber through a multi-channel gas distribution system to control the gas pressure within a preset range; S12, activate the semiconductor cooling module to reduce the temperature of the inner wall of the cavity from room temperature to -35°C at a step rate and maintain the current temperature; S13, when the fluctuation range of the cavity vacuum monitoring value is less than the predetermined fluctuation threshold, it is determined that the adsorption saturation state has been reached. The fluctuation range of the vacuum monitoring value in S13 is calculated as follows: ; in, P(t) represents the change in vacuum level per unit time, where P(t) is the vacuum level reading of the cavity at time t, and 10 min is the time window. The predetermined fluctuation threshold is set to 0.15 kPa / 10 min; When the fluctuation range of the cavity vacuum level monitoring value per unit time meets the following conditions: Furthermore, if this condition is met three times consecutively, it is determined that the test chamber has reached adsorption saturation. "Meeting three times consecutively" means that the fluctuation condition is less than 0.15 kPa in at least three adjacent time windows. S2 specifically includes: S21, while sending a start signal to the vacuum pump under test, triggers the ring-shaped distributed infrared heating module; S22, through infrared radiation of a preset wavelength, causes the temperature of the inner wall of the test chamber to rise from -35℃ to 65℃ at a rate of 12-15℃ / s. S23: The test chamber wall is collected in real time by thermocouple array and the temperature gradient of the test chamber wall is calculated. When the maximum local temperature difference is greater than the maximum temperature threshold, the compensation heater is started to perform temperature equalization control. The maximum local temperature difference is calculated as: ΔT max =max(T) i )-min(T i ), i=1,2,...,16; when ΔT max When the temperature exceeds 8℃, the compensation heater is activated, and the compensation power is dynamically adjusted according to the temperature difference in each zone. ； Among them, T i Let i be the temperature value measured by the i-th thermocouple. The average temperature at the current 16 points, ΔT max This represents the maximum temperature difference in the real-time temperature distribution of the cavity wall. This represents the output power of the compensation heater in region i.

2. The integrated vacuum pump testing method according to claim 1, characterized in that, The multi-channel gas distribution system is used to fill the sealed test chamber with a mixture of nitrogen and water vapor, specifically including: Nitrogen channel: includes nitrogen gas source and mass flow meter; Water vapor channel: includes an ultrasonic atomizing water vapor generator and an atomization rate control valve, wherein the atomization rate control valve adjusts the atomization flow rate according to the target output ratio; Gas mixing chamber: The nitrogen gas and water vapor are fully mixed in the gas mixing chamber, which is equipped with a stainless steel tubular static mixer; Proportional feedback control module: Real-time acquisition of flow information and chamber pressure data of nitrogen and water vapor channels; Adjustment of mass flow meter and atomization rate control valve through proportional-integral-derivative algorithm in main controller to ensure that the volume ratio of mixed gas is controlled at 3:

1.

3. The integrated vacuum pump testing method according to claim 1, characterized in that, The infrared heating module uses multiple sets of infrared heaters arranged in a ring, with a radiation wavelength covering 2.5–4.0 μm.

4. The integrated vacuum pump testing method according to claim 1, characterized in that, S3 specifically includes: S31, the amount of gas released during the desorption process ΔQ is monitored in real time by a quadrupole mass spectrometer; S32, a capacitive thin-film vacuum gauge is used to record the vacuum degree change curve, and the desorption time t corresponding to the time constant τ is extracted; S33, Calculate the average vacuum level P m ; S34, output the adsorbed gas release rate η according to the formula for the adsorbed gas release rate. When the standard deviation of the η value is less than the data validity standard deviation threshold after multiple consecutive calculations, the data is determined to be valid.

5. The integrated vacuum pump testing method according to claim 4, characterized in that, The gas release amount ΔQ is calculated as follows: ; Where k is the cavity volume calibration coefficient, A i Let A be the peak area corresponding to mass number 18 in the i-th sampling. base denoted as the baseline area of ​​the mass channel, and n as the number of samplings during the desorption process.

6. The integrated vacuum pump testing method according to claim 5, characterized in that, The formula for calculating the adsorbed gas release rate is as follows: .

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