Device and method for testing performance of crimping type insulated gate bipolar transistor in deep sea salt mist environment

Abstract

The invention relates to a device and method for testing the performance of a crimping type insulated gate bipolar transistor in a deep sea salt mist environment, and the device comprises a to-be-tested IGBT, an electrical test loop, an IGBT module installation region, a sprayer, a PID controller, a salt water tank, and a salt mist box. Wherein the IGBT module installation area is arranged in the salt mist box, one end of the sprayer is connected with the side face of the IGBT module installation area through a spraying pipeline, the other end of the sprayer penetrates through the top of the IGBT module installation area through a recycling pipeline to be connected with the interior of the IGBT module installation area, and the PID controller is connected with the sprayer and the salt water tank through a pipeline and a data transmission line. One side of the salt water tank is connected with one side of the salt mist box; an IGBT to be tested is installed in the IGBT module installation area and is connected with the electrical test loop through a waterproof circuit, and the electrical test loop is installed outside the salt mist box. Compared with the prior art, different deep and far sea environment fluctuations in practical application can be simulated more truly.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment insulation technology, and in particular to a performance testing device and method for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment. Background Technology

[0002] Existing salt spray environment performance tests are mainly conducted through standards such as ISO 9227 and GB / T 10125. These standards are used to evaluate the corrosion resistance of metals and coatings in salt spray environments and are widely used in corrosion resistance testing of metal parts and coatings.

[0003] However, the commonly used methods are mainly designed for conventional atmospheric salt spray environments and do not fully cover the comprehensive environmental factors under special conditions in deep sea. For example, Chinese patent application CN114325251A discloses a salt spray simulation device and testing method for power distribution conductors, including a salt spray concentration test sensor connected inside a salt spray chamber. The salt spray chamber is connected to a box body with a built-in ultrasonic atomizing plate through a first connecting pipe. The ultrasonic atomizing plate is connected to a water tank through a second connecting pipe. The concentration inside the salt spray chamber can be adjusted by adjusting the ultrasonic atomizing plate and louvers, which can only simply adjust the smoke concentration.

[0004] The salt spray environment in deep-sea areas is characterized by significant concentration fluctuations, persistent high humidity, and strong wind coupling, resulting in environmental stresses that differ significantly from conventional salt spray conditions in laboratories. Furthermore, existing standards focus on evaluating the corrosion behavior of metallic materials and fail to provide specialized testing for the structural characteristics, electrical contact reliability, and long-term performance degradation mechanisms of power electronic modules such as press-fit insulated gate bipolar transistors (IGBTs). Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by providing a performance testing device and method for press-fit insulated gate bipolar transistors in deep-sea salt spray environments. By introducing a PID control system, the salt spray concentration can be dynamically adjusted according to real-time feedback during the test, ensuring that the salt spray environment is kept within the set range. This avoids the limitations of traditional methods where the concentration is fixed and cannot be adjusted, thus more realistically simulating the fluctuations of different deep-sea environments in actual applications.

[0006] The objective of this invention can be achieved through the following technical solutions: A performance testing device for a press-fit insulated gate bipolar transistor (IGBT) in a deep-sea salt spray environment includes the IGBT under test. The device comprises an electrical test circuit, an IGBT module mounting area, a sprayer, a PID controller, a salt water tank, and a salt spray chamber. The IGBT module installation area is located inside the salt spray chamber. One end of the sprayer is connected to the side of the IGBT module installation area via a spray pipe, and the other end is connected to the inside of the IGBT module installation area via a recovery pipe passing through the top of the IGBT module installation area. The PID controller is connected to the sprayer and the salt tank via a pipeline and a data transmission line. One side of the salt tank is connected to one side of the salt spray chamber. The IGBT under test is installed in the IGBT module installation area and connected to the electrical test circuit via a waterproof line. The electrical test circuit is installed outside the salt spray chamber.

[0007] Furthermore, the device also includes a computer interface module for receiving simulated parameters of deep-sea salt fog environment, the computer interface module being connected to the PID controller and the brine tank respectively via data transmission lines.

[0008] Furthermore, the salt spray chamber is equipped with sensors, which are connected to the computer interface module via a data transmission line. The sensors include a salt spray concentration sensor.

[0009] Furthermore, the electrical test circuit is used for voltage, current, and temperature monitoring.

[0010] A performance testing method for a press-fit insulated gate bipolar transistor based on the performance testing device for deep-sea salt spray environments as described above, the method comprising: The simulation parameters of the deep-sea salt fog environment are input through the computer interactive interface module; Install the IGBT under test in the IGBT module mounting area and connect it to the electrical test circuit; The simulation parameters of the deep-sea salt fog environment are sent to the PID controller through the computer interface. The PID controller controls the sprayer to draw and atomize salt water from the salt tank according to the simulation parameters of the deep-sea salt fog environment, and generates the target salt fog environment in the salt fog chamber. Within a preset time period, environmental measurement data is continuously collected by the sensors inside the salt spray chamber, and electrical parameters of the IGBT are continuously collected by the electrical test circuit. The collected environmental measurement data and electrical parameters are analyzed to calculate the performance changes of IGBTs under different salt spray concentrations. Based on the calculation results and preset qualification standards, the performance of IGBTs in the salt spray environment is evaluated.

[0011] Furthermore, the electrical parameters of the IGBT under test include its voltage, current, contact resistance, and switching frequency.

[0012] Furthermore, the simulation parameters of the deep-sea salt fog environment include the target salt fog concentration, spray cycle and duty cycle, test chamber temperature and humidity settings, test time and data acquisition time.

[0013] Furthermore, the process of evaluating the performance of the IGBT under salt spray conditions includes: Based on the electrical parameters, the on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are calculated. The on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are compared with preset qualification standards. If all of them are better than the preset qualification standards, the performance evaluation result of the IGBT in the salt spray environment is determined to be qualified; otherwise, it is determined to be unqualified.

[0014] Furthermore, if the performance evaluation result of the IGBT under test in the salt spray environment is satisfactory, then all test data, environmental records and analysis results are compiled and a detailed performance test and evaluation report is automatically generated.

[0015] Furthermore, if the performance evaluation result of the IGBT under test in the salt spray environment is that the performance does not meet the standard, then a failure analysis is performed on the calculation result that is lower than the preset qualified standard, the stress conditions of the salt spray environment are adjusted, or optimization suggestions are made on the design, process and materials of the IGBT under test itself, and the corresponding conditions are adjusted. The performance test is then performed again under the adjusted conditions.

[0016] Compared with the prior art, the beneficial effects of the present invention include: 1. Dynamic Adjustment of Salt Fog Concentration: This technical solution introduces a PID control system to adjust the salt fog concentration in real time, simulating the characteristics of salt fog concentration fluctuations in different deep-sea salt fog environments. Compared with traditional methods, this dynamic adjustment can accurately reflect the salt fog concentration in deep-sea environments, improving the accuracy and reliability of the test and reducing test errors caused by concentration fluctuations.

[0017] 2. Multi-concentration test design: This scheme sets up different salt spray concentration gradients, and gradually adjusts the concentration through a PID control system, enabling a comprehensive evaluation of the impact of different salt spray concentrations on IGBT performance, especially changes in contact resistance. This innovative design provides more diversified test conditions, making the equipment design more adaptable to different salt spray environments, and improving the reliability of product corrosion resistance and long-term reliability testing.

[0018] 3. Long-term exposure and performance evaluation: This technical solution incorporates long-term exposure testing to evaluate the long-term performance changes of IGBT modules under different salt spray concentrations. Compared with short-term testing methods, this long-term test can comprehensively evaluate the degradation and failure of IGBTs in salt spray environments, helping manufacturers optimize designs, improve the stability and reliability of equipment in harsh environments, and extend product lifespan.

[0019] 4. Comprehensive Evaluation of Electrical Performance and Contact Stability: By combining salt spray concentration adjustment and long-term exposure testing, this approach comprehensively evaluates issues such as electrical performance degradation and poor contact in IGBT modules, especially under long-term exposure environments. This innovative method helps manufacturers better understand the long-term performance of their devices in salt spray environments, thereby optimizing electrical contact and packaging design and improving the overall reliability and stability of their products. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the salt spray test apparatus of the present invention; Figure 2 This is a schematic diagram of the working principle of the PID control system of the present invention; Figure 3 This is a connection diagram of the IGBT module and the electrical test circuit of the present invention; Figure 4 This is a logic diagram of the salt spray test system of the present invention; Figure 5 This is a flowchart of the salt spray test of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0022] Example 1 This embodiment discloses a performance testing device for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment, such as... Figure 1 As shown, the device includes the IGBT under test, an electrical test circuit, an IGBT module mounting area 1, a sprayer 2, a PID controller 3, a salt water tank 4, and a salt spray chamber 5.

[0023] The core of the device is a salt spray chamber 5. The IGBT module installation area 1 is set inside the salt spray chamber 5. One end of the sprayer 2 is connected to the side of the IGBT module installation area 1 through a spray pipe, and the other end is connected to the inside of the IGBT module installation area 1 through a recovery pipe. The PID controller 3 is connected to the sprayer 2 and the brine tank 4 through a pipeline and a data transmission line. One side of the brine tank 4 is connected to one side of the salt spray chamber 5.

[0024] The IGBT under test is installed in the IGBT module installation area 1 and connected to the electrical test circuit through a waterproof line. The electrical test circuit is installed outside the salt spray chamber 5.

[0025] The sprayer is connected to the brine tank 4 via a pipeline. The brine tank 4 is used to store and supply brine of a specific concentration to simulate a deep-sea environment. An external PID controller 3 is installed in the salt spray chamber 5. The PID controller 3 is configured to... Figure 2 The control system shown is used to receive sensor signals and precisely control the working state of the sprayer 2.

[0026] The device also includes a computer interface module for receiving simulated parameters of the deep-sea salt spray environment. This computer interface module is connected to the PID controller 3 and the brine tank 4 via data transmission lines, forming a complete closed-loop testing system. The overall layout clearly demonstrates the integrated design of salt spray environment simulation, sample installation, and automated control.

[0027] The salt spray chamber 5 is equipped with sensors, which are connected to the computer interface module via data transmission lines. The sensors include a salt spray concentration sensor.

[0028] Electrical test circuits such as Figure 3 As shown, it includes a voltage, current and temperature monitoring system, where G is the gate, C is the collector and E is the emitter.

[0029] Example 2 This embodiment, based on Embodiment 1 above, discloses a performance testing method for a performance testing device for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment as described above. The method is as follows: Figure 5 The test process shown below includes the following specific test steps: Step S101, Salt spray test environment setting: Input the simulation parameters of the deep-sea salt spray environment through the computer interactive interface module; Step S102, IGBT module installation: Install the IGBT under test in IGBT module installation area 1 and connect it to the electrical test circuit, such as... Figure 3 As shown; Step S103: Start the test system: Simulation parameters of the deep-sea salt fog environment are sent to the PID controller 3 via the computer interface. The PID controller 3, based on these parameters, controls the sprayer 2 to draw and atomize salt water from the salt water tank 4, generating the target salt fog environment within the salt fog chamber 5. Simultaneously, various sensors installed within the chamber, such as the salt fog concentration sensor, continuously collect environmental "measurement data" and feed it back to the computer, forming a data set. Figure 4 The closed-loop control circuit shown ensures the accuracy and stability of environmental parameters. Under this environment, the electrical performance of the IGBT module is tested. The test circuit principle is shown below. Figure 3 And began collecting its performance data in real time; Step S104, Long-term exposure test: The IGBT module is subjected to long-term exposure for a specified period, such as 72 hours to several weeks, under the stable salt spray environment set in step S103 to simulate its long-term service conditions in the extreme environment of the deep sea. Throughout the exposure period, the system continuously monitors and records environmental parameters and intermittent or periodic performance data of the module; Step S105, Performance Data Analysis and Evaluation: After the long-term exposure test, analyze the collected environmental measurement data and electrical parameters, calculate the performance changes of IGBTs under different salt spray concentrations, and evaluate the performance of IGBTs in the salt spray environment based on the calculation results and the preset qualification standards.

[0030] Step S106, Performance Compliance Determination: Based on the analysis results of step S105, and according to preset qualification standards such as performance degradation rate not exceeding a certain threshold, determine whether the performance of the tested IGBT module meets the standards. Figure 5 As shown, this judgment determines the subsequent process; Step S107, Generate Test Report: If step S106 determines "yes" and the performance meets the standard, the process ends, and the system organizes all test data, environmental records and analysis results to automatically generate a detailed performance test and evaluation report. Step S108, Adjust parameters or optimize design: If step S106 determines "no" and the performance does not meet the standard, proceed to this step. Based on the failure analysis results, adjust the salt spray environment stress conditions, or propose optimization suggestions for the design, process, and materials of the IGBT itself. After that, the process can return to step S101 and retest and verify under the adjusted conditions.

[0031] The electrical parameters of the IGBT under test include its voltage, current, contact resistance, and switching frequency.

[0032] The simulation parameters for deep-sea salt spray environments include target salt spray concentration, spray cycle and duty cycle, test chamber temperature and humidity settings, test time and data acquisition time.

[0033] In step S103, the PID controller 3 controls the sprayer 2 to draw and atomize salt water from the salt water tank 4 and generate the target salt spray environment in the salt spray chamber 5 based on the simulation parameters of the deep-sea salt spray environment. The PID control formula is as follows: in, This is a proportionality coefficient used to control the sensitivity of salt spray intensity to the current concentration deviation. This is the integral coefficient, used to eliminate steady-state errors and ensure that the concentration remains accurately at the target value over a long period. This is the differential coefficient, used to suppress abrupt changes in concentration and improve the smoothness of salt spray concentration variations.

[0034] In PID control, the output signal u(t) drives the following actuators: Sprayer spray pressure; Spray valve opening; Spray pulse duty cycle; Salt solution pump flow rate; During PID control, the proportional coefficient is adjusted so that when u(t)>0, the salt spray concentration in the device is increased (e.g., by increasing the sprayer's injection pressure, increasing the spray valve opening, etc.), and the further u(t) deviates from the origin, the stronger the adjustment force; conversely, the further it deviates from the origin, the lower the salt spray concentration in the device.

[0035] In step S105, the collected environmental measurement data and electrical parameters are preprocessed before analysis. The preprocessing specifically includes: ① Filtering: Used to remove noise and ensure data authenticity; The raw data is initially screened to distinguish between environmental measurement data from sensors inside the salt spray chamber and electrical parameters from electrical test circuits. The environmental measurement data includes salt spray concentration and humidity, while the electrical parameters include voltage, current, contact resistance, and switching frequency. Identify the noise characteristics of two types of data: environmental data noise is mostly random high-frequency fluctuations, while electrical parameter noise may contain electromagnetic coupling interference and transient anomalies caused by poor contact. Based on noise characteristics, different filtering methods are adopted. For environmental data, the moving average filtering method is used, and the sliding window size is set according to the acquisition frequency. For electrical parameters, Kalman filtering or a combination of median filtering and moving average is used. Median filtering removes peak outliers, and then moving average is used to smooth the remaining fluctuations. Kalman filtering requires preset process noise variance based on the electrical characteristics of the IGBT module and preset observation noise variance based on the accuracy of the test circuit. Obtain the filtered data sequence and verify the filtering effect using the 3σ criterion: calculate the mean μ and standard deviation σ of the filtered data, remove the remaining outliers that exceed the range of [μ-3σ, μ+3σ], and fill in the gaps using linear interpolation of adjacent data to avoid data breaks.

[0036] ② Discretization and synchronization processing: used to unify data dimensions and achieve spatiotemporal matching; Data acquisition frequency and timestamp standardization: Extract timestamps from all raw data to determine the baseline sampling frequency: Using the acquisition frequency of electrical parameters as the baseline, downsample the continuous acquisition frequency of environmental data to the baseline frequency; if the acquisition time of electrical parameters is irregular, use linear interpolation to fill in the missing values ​​of the baseline time nodes; Time axis alignment and data windowing: A unified time axis is constructed with the test start time as the origin, and all filtered data is mapped to discrete nodes of this time axis; the data is windowed according to the test stage, and the data is divided into sub-windows such as "environmental stability stage, long-term exposure stage and concentration adjustment stage", ensuring that the time nodes of environmental data and electrical parameters correspond one-to-one within each window; Discretized data format standardization: integrate multi-dimensional data at each time point into a time-parameter sample vector with unified sample vector dimensions.

[0037] ③ Normalization: Used to eliminate dimensional differences and support cross-parameter comparison; Parameter classification and value range determination: Parameters are classified by type into environmental (salt spray concentration, humidity), electrical performance (voltage, current, switching frequency), and contact characteristics (contact resistance). The maximum and minimum values ​​of each type of parameter in all discrete samples are calculated, and the value range is recorded. The influence of outliers on the range is eliminated. If a parameter has extreme outliers, they have been eliminated in the filtering stage. Here, the maximum and minimum values ​​are calculated only based on valid data. Normalization calculation: The Min-Max normalization method is adopted. For all parameters in each time-parameter sample vector, the normalized value is calculated according to the maximum and minimum values ​​of the corresponding categories, and the time normalized parameter vector is generated. The mapping table between the original parameter values ​​and the normalized values ​​is retained to facilitate subsequent reverse tracing.

[0038] The overall preprocessing process is as follows: raw data → filtering (denoising) → discretization and synchronization (spatiotemporal matching) → normalization (dimensional unification) → for subsequent performance analysis.

[0039] Each preprocessing stage generates intermediate data files containing original values, processed values, parameter configurations, and processing time, facilitating traceability and reproducibility. The final normalized data is stored according to the test stage and salt spray concentration gradient, supporting multi-dimensional analysis needs.

[0040] The process of evaluating the performance of IGBTs in a salt spray environment includes: Based on electrical parameters, the on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are calculated. The on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are compared with the preset pass / fail standards. If all of them are better than the preset pass / fail standards, the performance evaluation result of the IGBT in the salt spray environment is judged to meet the standards; otherwise, it is judged to fail to meet the standards.

[0041] In another embodiment, the performance evaluation process includes: Calculate performance drift: Find the change of each physical quantity relative to its initial value; The coupling relationship between environmental stress and performance changes is analyzed, and its expression is as follows: in, Salt spray concentration, For exposure time, and As weight, This refers to a performance drift. Based on the performance drift obtained by comparing with literature and qualification standards, the performance degradation is specifically analyzed using models, including the exponential decay model, the piecewise linear degradation model, and the threshold drift model.

[0042] If the performance evaluation result of the IGBT under test in the salt spray environment is satisfactory, then all test data, environmental records and analysis results will be compiled and a detailed performance test and evaluation report will be automatically generated.

[0043] If the performance evaluation result of the IGBT under test in the salt spray environment is that the performance does not meet the standard, then a failure analysis is performed on the calculation result that is lower than the preset qualified standard, the stress conditions of the salt spray environment are adjusted, or optimization suggestions are made on the design, process and materials of the IGBT under test itself, and the corresponding conditions are adjusted. The performance test is then carried out again under the adjusted conditions.

[0044] The failure analysis process and optimization suggestions in this embodiment are based on existing research on IGBT failure mechanisms, and the process specifically includes: 1. Input the test results; 2. Based on existing conclusions, such as: Increased contact resistance suggests that salt spray corrosion leads to oxidation and contact degradation at the crimped interface. Increased VCE leads to increased thermal resistance at the chip-substrate interface and deterioration of heat transfer due to corrosion. Increased leakage current – ​​surface insulation layer damaged by salt spray and damp heat; Increased switching energy – deterioration of internal parasitic parameters leading to increased energy loss; The final failure analysis conclusions were obtained.

[0045] Examples of optimization conclusions are as follows: Increased contact resistance: Improve the crimping interface material (gold plating, nickel plating) to enhance oxidation resistance; Salt spray penetration leads to corrosion: Strengthen by adding sealing rings and epoxy resin encapsulation; Increased thermal resistance: Optimize heat sink structure and contact flatness; Surface insulation degradation: Add anti-salt spray coating (silicone film, fluorinated film); Long-term performance drift: Adjust the clamping force and improve the interface roughness.

[0046] Example 3 Based on Embodiment 2, this embodiment provides an electronic device, including: one or more processors and a memory, wherein the memory stores one or more programs, and the one or more programs include instructions for executing the performance testing method described above.

[0047] At the hardware level, the electronic device includes a processor, internal bus, network interface, memory, and non-volatile memory, and may also include other hardware required for business operations. The processor reads the corresponding computer program from the non-volatile memory into memory and then runs it to implement the performance testing method described above. Of course, in addition to software implementation, this invention does not exclude other implementation methods, such as logic devices or a combination of hardware and software, etc. That is to say, the execution subject of the following processing flow is not limited to individual logic units, but can also be hardware or logic devices.

[0048] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0049] Computer-readable media include both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0050] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A performance testing device for a press-fit insulated gate bipolar transistor (IGBT) in a deep-sea salt spray environment, comprising the IGBT under test, characterized in that, The device also includes an electrical test circuit, an IGBT module mounting area (1), a sprayer (2), a PID controller (3), a salt water tank (4), and a salt spray chamber (5); wherein, The IGBT module installation area (1) is located inside the salt spray chamber (5). One end of the sprayer (2) is connected to the side of the IGBT module installation area (1) through a spray pipe, and the other end is connected to the inside of the IGBT module installation area (1) through a recovery pipe. The PID controller (3) is connected to the sprayer (2) and the salt water tank (4) through a pipeline and a data transmission line. One side of the salt water tank (4) is connected to one side of the salt spray chamber (5). The IGBT under test is installed in the IGBT module installation area (1) and connected to the electrical test circuit through a waterproof line. The electrical test circuit is installed outside the salt spray chamber (5).

2. The performance testing device for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment according to claim 1, characterized in that, The device also includes a computer interface module for receiving simulation parameters of deep-sea salt fog environment. The computer interface module is connected to the PID controller (3) and the brine tank (4) respectively via data transmission lines.

3. The performance testing device for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment according to claim 2, characterized in that, The salt spray chamber (5) is equipped with a sensor, which is connected to the computer interface module via a data transmission line. The sensor includes a salt spray concentration sensor.

4. The performance testing device for a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment according to claim 1, characterized in that, The electrical test circuit is used for voltage, current and temperature monitoring.

5. A performance testing method for a performance testing device based on a press-fit insulated gate bipolar transistor in a deep-sea salt spray environment as described in any one of claims 2-3, characterized in that, The method includes: The simulation parameters of the deep-sea salt fog environment are input through the computer interactive interface module; The IGBT to be tested is installed in the IGBT module installation area (1) and connected to the electrical test circuit; The simulation parameters of the deep-sea salt fog environment are sent to the PID controller (3) through the computer interface. The PID controller (3) controls the sprayer (2) to draw and atomize salt water from the salt water tank (4) according to the simulation parameters of the deep-sea salt fog environment, and generates the target salt fog environment in the salt fog box (5). Within a preset time period, environmental measurement data is continuously collected by the sensors inside the salt spray chamber (5), and electrical parameters of the IGBT are continuously collected by the electrical test circuit. The collected environmental measurement data and electrical parameters are analyzed to calculate the performance changes of IGBTs under different salt spray concentrations. Based on the calculation results and preset qualification standards, the performance of IGBTs in the salt spray environment is evaluated.

6. The performance testing method according to claim 5, characterized in that, The electrical parameters of the IGBT under test include its voltage, current, contact resistance, and switching frequency.

7. The performance testing method according to claim 5, characterized in that, The simulation parameters for the deep-sea salt spray environment include the target salt spray concentration, spray cycle and duty cycle, test chamber temperature and humidity settings, test time and data acquisition time.

8. The performance testing method according to claim 5, characterized in that, The process of evaluating the performance of the IGBT in a salt spray environment includes: Based on the electrical parameters, the on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are calculated. The on-state voltage drop, leakage current, and threshold voltage drift of the IGBT under test are compared with preset qualification standards. If all of them are better than the preset qualification standards, the performance evaluation result of the IGBT in the salt spray environment is determined to be qualified; otherwise, it is determined to be unqualified.

9. A performance testing method according to claim 8, characterized in that, If the performance evaluation result of the IGBT under test in the salt spray environment is satisfactory, then all test data, environmental records and analysis results will be compiled and a detailed performance test and evaluation report will be automatically generated.

10. A performance testing method according to claim 8, characterized in that, If the performance evaluation result of the IGBT under test in the salt spray environment is that the performance does not meet the standard, then a failure analysis is performed on the calculation result that is lower than the preset qualified standard, the stress conditions of the salt spray environment are adjusted, or optimization suggestions are made on the design, process and materials of the IGBT under test itself, and the corresponding conditions are adjusted. The performance test is then performed again under the adjusted conditions.

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