High-voltage rectifier diode full-parameter on-line detection system and detection method

Abstract

This invention discloses a full-parameter online detection system and method for high-voltage rectifier diodes, comprising a detection probe module, a signal conditioning module, a data acquisition module, and a main control module connected in sequence, and a high-voltage excitation module, a temperature compensation module, a data storage module, a display and alarm module, and a communication module, all electrically connected to the main control module. This full-parameter online detection system and method for high-voltage rectifier diodes effectively filters out electromagnetic interference and temperature drift in high-voltage scenarios by employing a high-precision detection probe, multi-stage filtering circuits, opto-isolation technology, and a temperature compensation mechanism. The detection accuracy reaches over 0.5%, and the leakage current measurement accuracy can reach the nA level, significantly reducing the risk of false positives and false negatives. Simultaneously, the pulse excitation method avoids interference with the normal operation of the device under test during the detection process, achieving interference-free online detection.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device testing-related products, specifically to an online testing system and method for full parameters of a high-voltage rectifier diode. Background Technology

[0002] High-voltage rectifier diodes are core components in power electronic systems, and their performance parameters directly determine the system's stability, reliability, and safety. They are widely used in high-voltage power supplies, pulse power supplies, and industrial high-voltage modules. Key performance parameters of high-voltage rectifier diodes include reverse breakdown voltage (VBR), forward conduction voltage (VF), leakage current (IR), junction capacitance (Cj), thermal resistance (RθJC), and reverse recovery time (trr). Abnormal changes in these parameters can lead to device failure, resulting in system malfunctions and even safety hazards.

[0003] Currently, the testing methods for high-voltage rectifier diodes are mainly divided into two categories: offline testing and online testing. Offline testing requires removing the device from the working system and measuring parameters using specialized testing equipment. This method is cumbersome, inefficient, and cannot achieve real-time status monitoring during device operation, making it difficult to meet the online testing needs of industrial production and equipment maintenance. Existing online testing technologies have significant drawbacks: First, they only measure a limited number of parameters, such as leakage current and forward voltage, failing to achieve full parameter coverage and making it difficult to comprehensively evaluate device performance. Second, they have low testing accuracy; electromagnetic interference and temperature drift in high-voltage scenarios can lead to significant deviations in the test data, resulting in a high risk of false positives and false negatives. Third, they have poor adaptability, failing to adapt to different models and rated parameters of high-voltage rectifier diodes, and the testing process can easily interfere with the normal operation of the device. Fourth, they lack effective data processing and fault prediction mechanisms; they can only collect parameters and cannot analyze abnormal parameter trends, making it difficult to prevent safety hazards caused by fault escalation in advance.

[0004] For example, the fault detection system for diode comprehensive performance disclosed in existing patent CN121831453A mainly evaluates the diode's operational instability characteristics by extracting ripple loss features, focusing on fault early warning, but it cannot achieve accurate online detection of multiple key parameters of high-voltage rectifier diodes. CN117214650B discloses an intelligent detection method and system for diode comprehensive performance, which achieves batch testing, but its adaptability to high-voltage scenarios is insufficient, and it does not cover core parameters of high-voltage rectifier diodes such as junction capacitance and thermal resistance coefficient. Furthermore, existing testing equipment often suffers from limited testing range and insufficient accuracy. For instance, ordinary withstand voltage testers cannot meet the accurate detection requirements of reverse breakdown voltage for high-voltage rectifier diodes above 10kV, and leakage current measurement accuracy is difficult to reach the nA level, failing to meet the testing requirements in high-voltage scenarios. Summary of the Invention

[0005] The purpose of this invention is to provide an online detection system and method for all parameters of a high-voltage rectifier diode, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-voltage rectifier diode full-parameter online detection system, comprising a detection probe module, a signal conditioning module, a data acquisition module, and a main control module connected in sequence, and a high-voltage excitation module, a temperature compensation module, a data storage module, a display alarm module, and a communication module respectively connected to the main control module; the detection probe module is detachably connected to the high-voltage rectifier diode under test and is used to acquire the electrical signal and temperature signal of the device under test; the high-voltage excitation module is used to provide suitable forward and reverse excitation signals for the high-voltage rectifier diode under test to meet the detection requirements of different parameters.

[0007] In a preferred embodiment of the present invention, the detection probe module includes a voltage detection probe, a current detection probe, a temperature detection probe, and a junction capacitance detection probe. The voltage detection probe is a high-voltage differential probe with a measurement range of 0-200kV and an accuracy of 0.5%, used to acquire the forward conduction voltage and reverse breakdown voltage signals of the high-voltage rectifier diode under test. The current detection probe is a high-precision Hall current sensor with a range of 0.1nA-10mA, used to acquire the leakage current and forward conduction current signals of the device under test. The temperature detection probe is a non-contact infrared temperature sensor with a temperature measurement range of 25℃-175℃, used to acquire the junction temperature signal of the device under test. The junction capacitance detection probe is a high-frequency LCR detection probe with a test frequency of 1MHz and an accuracy of ±2%, used to acquire the junction capacitance signal of the device under test.

[0008] In a preferred embodiment of the present invention, the high-voltage excitation module includes a forward excitation unit, a reverse excitation unit, and an excitation adjustment unit. The forward excitation unit is used to output an adjustable forward DC voltage of 0-50V to provide forward conduction current. The reverse excitation unit is used to output an adjustable reverse DC voltage of 0-200kV for reverse breakdown voltage and leakage current detection. The excitation adjustment unit adjusts the amplitude and output rate of the excitation voltage and current based on the control signal of the main control module, adapting to high-voltage rectifier diodes of different models and rated parameters. It also adopts a pulse excitation method to reduce the interference of the excitation signal on the normal operation of the device under test and avoid damage to the device due to prolonged high-voltage excitation.

[0009] As a preferred embodiment of the present invention, the signal conditioning module includes a filtering unit, an amplification unit, and an isolation unit; the filtering unit adopts a multi-stage RC filter circuit to filter out electromagnetic interference signals and environmental noise in high-voltage scenarios; the amplification unit adopts a high-precision instrumentation amplifier to amplify weak signals such as leakage current and junction capacitance, with an adjustable amplification factor (10-1000 times) to ensure the accuracy of signal acquisition; the isolation unit adopts opto-isolation technology to achieve electrical isolation between the detection circuit and the working circuit of the device under test, avoiding interference from the detection system to the normal operation of the device, while ensuring the safety of testing personnel and equipment.

[0010] As a preferred embodiment of the present invention, the data acquisition module adopts a high-speed ADC acquisition chip with a sampling frequency of up to 1MHz and a sampling accuracy of 16 bits. It is used to convert the analog signal output by the signal conditioning module into a digital signal and transmit it to the main control module. The data acquisition module supports multi-channel synchronous acquisition and can simultaneously acquire multiple types of signals such as voltage, current, temperature, and junction capacitance to ensure the synchronization of parameter detection.

[0011] In a preferred embodiment of the present invention, the main control module employs an ARM Cortex-M4 core microcontroller, integrating a data processing unit, a parameter calibration unit, and a fault prediction unit. The data processing unit is used to analyze and calculate the acquired digital signals to obtain various performance parameters of the high-voltage rectifier diode under test, including reverse breakdown voltage, forward conduction voltage, leakage current, junction capacitance, thermal resistance coefficient, and reverse recovery time. The parameter calibration unit calibrates the test data based on preset standard parameters and environmental compensation coefficients to eliminate the influence of temperature, humidity, and electromagnetic interference on the test accuracy. The fault prediction unit uses a trend analysis algorithm based on historical test data to predict the parameter change trend, and triggers an alarm signal when the parameter approaches the threshold or experiences an abnormal sudden change.

[0012] In a preferred embodiment of the present invention, the temperature compensation module is electrically connected to the temperature detection probe and the main control module, and is used to collect the ambient temperature signal and transmit the temperature compensation coefficient to the main control module. The main control module corrects the detection data based on the temperature compensation coefficient to ensure the accuracy of the detection data under different ambient temperatures. The compensation range of the temperature compensation module is -40℃ to 180℃, which is suitable for the detection needs of different working environments.

[0013] As a preferred embodiment of the present invention, the data storage module adopts an SD card or a Flash storage chip to store detection parameters, calibration data, historical detection records and fault information, with a storage capacity of not less than 16GB, supporting data retention even after power failure, facilitating subsequent data query, tracing and analysis; the display alarm module includes an LCD screen and an audible and visual alarm, the LCD screen is used to display various detection parameters, device status and fault information in real time, and the audible and visual alarm is used to issue an alarm prompt when parameters are abnormal or faults occur, and the alarm mode can be manually set.

[0014] As a preferred embodiment of the present invention, the communication module supports one or more of RS485, Ethernet, and WiFi communication methods to enable communication between the detection system and the host computer and IoT platform. It can upload detection data and fault information to the host computer in real time, facilitating remote monitoring, data management, and batch device testing. The system also includes a power supply module to provide a stable power supply for each module. The power supply module supports wide voltage input (12-24V) and has overvoltage, overcurrent, and short-circuit protection functions.

[0015] A method for online detection of all parameters of a high-voltage rectifier diode includes the following steps: Step 1, system initialization: The detection system is turned on, and the main control module performs self-tests on each module, checking the working status of the detection probe module, high-voltage excitation module, signal conditioning module, and data acquisition module. If any abnormality is found, an alarm is triggered and the fault location is indicated. At the same time, preset standard parameters, calibration data, and temperature compensation coefficients are loaded to complete the system initialization.

[0016] Step 2, Probe Connection and Parameter Setting: Connect the detection probe module to the high-voltage rectifier diode under test, ensuring a reliable connection; set the model, rated parameters (rated forward current, rated reverse voltage) and detection parameter thresholds of the device under test through the display alarm module or host computer. The main control module controls the high-voltage excitation module to adjust the excitation signal parameters according to the set parameters to adapt to the device under test.

[0017] Step 3, Multi-parameter synchronous acquisition: The main control module controls the high-voltage excitation module to output a forward excitation signal, and acquires the forward conduction voltage (VF) and forward conduction current signals of the device under test through the detection probe module; it controls the high-voltage excitation module to output a reverse excitation signal, and acquires the reverse breakdown voltage (VBR) and leakage current (IR) signals; at the same time, it acquires the junction capacitance (Cj) signal through the junction capacitance detection probe, and acquires the junction temperature and ambient temperature signals of the device under test through the temperature detection probe; all acquired analog signals are filtered, amplified, and isolated by the signal conditioning module, and then transmitted to the data acquisition module to be converted into digital signals, and then transmitted to the main control module.

[0018] Step 4, Data Processing and Calibration: The data processing unit of the main control module analyzes and calculates the acquired digital signals to obtain the original detection values ​​of various performance parameters; the parameter calibration unit calibrates the original detection values ​​based on the preset calibration data and the temperature compensation coefficient transmitted by the temperature compensation module to eliminate the influence of factors such as temperature and electromagnetic interference, and obtain accurate detection parameter values; at the same time, the thermal resistance coefficient (RθJC) is calculated based on the junction temperature and ambient temperature data, and the reverse recovery time (trr) is calculated based on the current change during forward and reverse excitation switching.

[0019] Step 5, Performance Evaluation and Fault Prediction: The main control module compares the calibrated detection parameter values ​​with preset thresholds to evaluate the performance status of the high-voltage rectifier diode under test. If all parameters are within the threshold range, the device is determined to be normal, and the detection parameters are displayed in real time. If any parameter exceeds the threshold, the device is determined to be abnormal, triggering an audible and visual alarm, and recording the fault parameters and fault time. At the same time, the fault prediction unit analyzes the parameter change trend based on historical detection data. If the parameters show an abnormal upward or downward trend and approach the threshold, an early warning signal is issued to prompt the staff to handle the situation in a timely manner.

[0020] Step 6, Data Storage and Transmission: The main control module stores accurate detection parameters, performance evaluation results, fault information, and historical detection records in the data storage module; at the same time, it uploads the detection data to the host computer or IoT platform in real time through the communication module, which facilitates remote monitoring, data query, and analysis; after the detection is completed, the detection can be stopped manually or an automatic detection cycle can be set to realize periodic online detection.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] This online detection system and method for high-voltage rectifier diodes effectively filters out electromagnetic interference and temperature drift in high-voltage scenarios by employing a high-precision detection probe, multi-stage filtering circuit, opto-isolation technology, and temperature compensation mechanism. The detection accuracy reaches over 0.5%, and the leakage current measurement accuracy can reach the nA level, significantly reducing the risk of false positives and false negatives. At the same time, the pulse excitation method is used to avoid interference with the normal operation of the device under test during the detection process, achieving interference-free online detection. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a high-voltage rectifier diode full-parameter online detection system according to the present invention;

[0024] Figure 2 This is a flowchart illustrating an online detection method for all parameters of a high-voltage rectifier diode according to the present invention. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0026] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] Please see Figure 1-2 The present invention provides an embodiment of a high-voltage rectifier diode full-parameter online detection system, comprising a detection probe module, a signal conditioning module, a data acquisition module, a main control module, a high-voltage excitation module, a temperature compensation module, a data storage module, a display and alarm module, a communication module, and a power supply module; the modules are electrically connected to each other through wires or interfaces to realize signal transmission and control.

[0029] The detection probe module adopts a detachable connection method and connects to the high-voltage rectifier diode under test. It is used to collect various electrical and temperature signals of the device under test, specifically including a voltage detection probe, a current detection probe, a temperature detection probe, and a junction capacitance detection probe. Among them, the voltage detection probe uses a Keysight high-voltage differential probe with a measurement range of 0-200kV and an accuracy of 0.5%, and is used to collect forward conduction voltage (VF) and reverse breakdown voltage (VBR) signals. The current detection probe uses a high-precision Hall current sensor with a range of 0.1nA-10mA, and is used to collect leakage current (IR) and forward conduction current signals. The temperature detection probe uses a miniature probe from the FLIRA655sc infrared thermal imager with a temperature measurement range of 25℃-175℃, and is used to collect junction temperature and ambient temperature signals of the device under test. The junction capacitance detection probe uses a probe matched with the Agilent E4980A LCR meter with a test frequency of 1MHz and an accuracy of ±2%, and is used to collect junction capacitance (Cj) signals.

[0030] The high-voltage excitation module includes a forward excitation unit, a reverse excitation unit, and an excitation adjustment unit. The forward excitation unit uses an adjustable DC power supply module, outputting an adjustable forward DC voltage of 0-50V and a maximum output current of 10A, used to provide forward conduction excitation for the device under test. The reverse excitation unit uses a high-voltage pulse power supply module, outputting an adjustable reverse DC pulse voltage of 0-200kV, with a pulse width adjustable from 0.5-5ms, used for reverse breakdown voltage and leakage current detection. The excitation adjustment unit uses a microcontroller-controlled relay module, which adjusts the amplitude and pulse parameters of the excitation voltage and current based on the control signal from the main control module, adapting to different types of high-voltage rectifier diodes, such as silicon-based high-voltage rectifier diodes and silicon carbide high-voltage rectifier diodes.

[0031] The signal conditioning module includes a filtering unit, an amplification unit, and an isolation unit. The filtering unit uses a two-stage RC filter circuit. The first stage is a low-pass filter with a cutoff frequency of 10kHz to filter out high-frequency electromagnetic interference, and the second stage is a notch filter to filter out 50Hz power frequency interference. The amplification unit uses an INA128 high-precision instrumentation amplifier with an adjustable amplification factor of 10-1000 times to amplify weak signals such as leakage current and junction capacitance. The isolation unit uses a TLP521 opto-isolator to achieve electrical isolation between the detection circuit and the working circuit of the device under test. The isolation voltage is ≥2500V to ensure detection safety and accuracy.

[0032] The data acquisition module uses the ADS8364 high-speed ADC acquisition chip, with a sampling frequency of 1MHz, a sampling accuracy of 16 bits, and supports 6-channel synchronous acquisition. It can simultaneously acquire signals such as voltage, current, temperature, and junction capacitance. After converting the analog signals into digital signals, they are transmitted to the main control module through the SPI interface.

[0033] The main control module uses an STM32F407 microcontroller (ARM Cortex-M4 core), integrating a data processing unit, a parameter calibration unit, and a fault prediction unit. The data processing unit analyzes and calculates the acquired digital signals to obtain various performance parameters. The thermal resistance coefficient (RθJC) is calculated using the difference between the junction temperature and the ambient temperature and the power consumption, while the reverse recovery time (trr) is calculated using the current change curves during forward and reverse excitation switching. The parameter calibration unit pre-stores calibration coefficients and temperature compensation formulas for different detection parameters and calibrates the original detection data. The fault prediction unit uses a linear regression algorithm to fit historical detection data, analyze parameter change trends, and achieve fault prediction.

[0034] The temperature compensation module uses a DS18B20 temperature sensor to collect ambient temperature signals and transmit them to the main control module. The main control module corrects the detection data based on the temperature compensation formula, with a compensation range of -40℃ to 180℃. The data storage module uses a 16GB SD card to store detection parameters, calibration data, historical detection records, and fault information, and supports power-off data retention. The display and alarm module includes a 2.4-inch LCD screen and an audible and visual alarm. The LCD screen displays various detection parameters and device status in real time, and the audible and visual alarm emits a red light and a buzzer when parameters are abnormal, with adjustable alarm volume. The communication module uses an ESP8266 WiFi module and an RS485 module, supporting WiFi and RS485 communication, and can upload detection data to a host computer or IoT platform. The power supply module uses an AC-DC power supply module with an input voltage of 110-220V and an output voltage of 12V and 5V, providing stable power to each module and featuring overvoltage, overcurrent, and short-circuit protection functions.

[0035] A method for online detection of all parameters of a high-voltage rectifier diode, based on a detection system, specifically includes the following steps:

[0036] Step 1, System Initialization: Power on the detection system. The main control module performs self-tests on each module, including the detection probe module, high-voltage excitation module, signal conditioning module, and data acquisition module, checking the working status of each module. If a module malfunctions (e.g., loose probe connection, abnormal output of the excitation module), the display alarm module will issue an audible and visual alarm and display the fault location on the LCD screen. Simultaneously, preset standard parameters (such as parameter thresholds for different types of high-voltage rectifier diodes), calibration data, and temperature compensation coefficients are loaded to complete system initialization, awaiting detection commands.

[0037] Step 2, Probe Connection and Parameter Setting: Reliably connect each probe of the detection probe module to the high-voltage rectifier diode under test. Connect the voltage detection probe in parallel across the two ends of the device under test, connect the current detection probe in series in the circuit of the device under test, align the temperature detection probe with the junction region of the device under test, and connect the junction capacitance detection probe to the pin of the device under test. Set the model of the device under test (e.g., MDD series high-voltage rectifier diode), rated parameters (rated forward current 10A, rated reverse voltage 100kV), and detection parameter thresholds (e.g., reverse breakdown voltage threshold ≥100kV, leakage current threshold ≤10nA) through the LCD display. The main control module controls the excitation adjustment unit of the high-voltage excitation module according to the set parameters, adjusting the forward excitation voltage to 10V, the reverse excitation voltage to 100kV, the pulse width to 2ms, and the pulse interval to 10ms.

[0038] Step 3, Multi-parameter synchronous acquisition: The main control module controls the high-voltage excitation module to first output a forward excitation signal, causing the high-voltage rectifier diode under test to conduct in the forward direction. The voltage detection probe acquires the forward conduction voltage (VF) signal, and the current detection probe acquires the forward conduction current signal. Subsequently, the high-voltage excitation module switches to a reverse excitation signal, outputting a reverse pulse voltage. The voltage detection probe acquires the reverse breakdown voltage (VBR) signal, and the current detection probe acquires the leakage current (IR) signal. Simultaneously, the junction capacitance detection probe acquires the junction capacitance (Cj) signal, and the temperature detection probe acquires the junction temperature and ambient temperature signals of the device under test. All acquired analog signals are filtered for interference by the signal conditioning module's filtering unit, amplified by the amplification unit (100x amplification factor), and isolated by the isolation unit before being transmitted to the data acquisition module. The data acquisition module converts the analog signals into digital signals and transmits them to the main control module via the SPI interface. The time deviation of multi-channel synchronous acquisition is controlled within 10μs to ensure the synchronization of parameter detection.

[0039] Step 4, Data Processing and Calibration: The data processing unit of the main control module analyzes and calculates the acquired digital signals to obtain the original detection values ​​of various performance parameters; the parameter calibration unit calibrates the original detection values ​​based on the preset calibration coefficients, and at the same time, according to the ambient temperature T transmitted by the temperature compensation module (assumed to be 35℃), it calls the temperature compensation formula: Vcalibration = V original × [1 + K × (T - T0)] (where K = 0.002 / ℃, T0 = 25℃) to correct the voltage parameters; for the leakage current signal, the corresponding temperature compensation formula: IR calibration = IR original × [1 + 0.01 × (T - T0)] is used for correction; based on the difference between the junction temperature (assumed to be 65℃) and the ambient temperature (35℃), combined with the forward conduction power consumption, the thermal resistance coefficient (RθJC) is calculated; based on the current change curve during forward and reverse excitation switching, the reverse recovery time (trr) is calculated, and finally, accurate detection parameter values ​​are obtained.

[0040] Step 5, Performance Evaluation and Fault Prediction: The main control module compares the calibrated detection parameter values ​​with preset thresholds. Assuming the detected reverse breakdown voltage is 102kV, leakage current is 8nA, forward conduction voltage is 1.2V, junction capacitance is 150pF, thermal resistance is 2.5℃ / W, and reverse recovery time is 50ns, all within the preset threshold range, the high-voltage rectifier diode under test is deemed to be performing normally, and the various detection parameters are displayed in real time on the LCD screen. If the detected leakage current is 15nA, exceeding the preset threshold (≤10nA), the device is deemed abnormal, and the audible and visual alarm is activated. At the same time, the fault parameters (leakage current 15nA) and fault time are recorded. The fault prediction unit calls up the detection data from the past 10 times and uses a linear regression algorithm to fit the leakage current change trend curve. If the leakage current is found to be increasing and the rate of change exceeds 0.5nA / time, an early warning signal is issued to prompt the staff to check the device status in time.

[0041] Step 6, Data Storage and Transmission: The main control module stores precise test parameters, performance evaluation results, fault information, and historical test records to the SD card for easy retrieval later. Simultaneously, the test data is uploaded to the host computer in real time via the WiFi module. The host computer can statistically analyze the test data and generate a test report. After the test is completed, the stop button can be pressed manually to end the test, or an automatic test cycle can be set (e.g., test every 30 minutes) to achieve periodic online testing and continuous monitoring of the performance status of the device under test.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-voltage rectifier diode full-parameter online detection system, characterized in that: The device includes a detection probe module, a signal conditioning module, a data acquisition module, and a main control module, which are connected in sequence. It also includes a high-voltage excitation module, a temperature compensation module, a data storage module, a display and alarm module, and a communication module, all electrically connected to the main control module. The detection probe module is detachably connected to the high-voltage rectifier diode under test and is used to acquire the electrical and temperature signals of the device under test. The high-voltage excitation module provides suitable forward and reverse excitation signals to the high-voltage rectifier diode under test to meet the detection requirements of different parameters.

2. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The detection probe module includes a voltage detection probe, a current detection probe, a temperature detection probe, and a junction capacitance detection probe. The voltage detection probe is a high-voltage differential probe with a measurement range of 0-200kV and an accuracy of 0.5%, used to acquire the forward conduction voltage and reverse breakdown voltage signals of the high-voltage rectifier diode under test. The current detection probe is a high-precision Hall current sensor with a range of 0.1nA-10mA, used to acquire the leakage current and forward conduction current signals of the device under test. The temperature detection probe is a non-contact infrared temperature sensor with a temperature measurement range of 25℃-175℃, used to acquire the junction temperature signal of the device under test. The junction capacitance detection probe is a high-frequency LCR detection probe with a test frequency of 1MHz and an accuracy of ±2%, used to acquire the junction capacitance signal of the device under test.

3. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The high-voltage excitation module includes a forward excitation unit, a reverse excitation unit, and an excitation adjustment unit. The forward excitation unit outputs an adjustable forward DC voltage of 0-50V to provide forward conduction current. The reverse excitation unit outputs an adjustable reverse DC voltage of 0-200kV for reverse breakdown voltage and leakage current detection. The excitation adjustment unit adjusts the amplitude and output rate of the excitation voltage and current based on the control signal from the main control module, adapting to high-voltage rectifier diodes of different models and rated parameters. It also adopts a pulse excitation method to reduce interference of the excitation signal with the normal operation of the device under test and avoid damage to the device due to prolonged high-voltage excitation.

4. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The signal conditioning module includes a filtering unit, an amplification unit, and an isolation unit. The filtering unit uses a multi-stage RC filter circuit to filter out electromagnetic interference signals and environmental noise in high-voltage scenarios. The amplification unit uses a high-precision instrumentation amplifier to amplify weak signals such as leakage current and junction capacitance, with an adjustable amplification factor (10-1000 times) to ensure the accuracy of signal acquisition. The isolation unit uses opto-isolation technology to achieve electrical isolation between the detection circuit and the working circuit of the device under test, avoiding interference from the detection system to the normal operation of the device, while ensuring the safety of testing personnel and equipment.

5. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The data acquisition module uses a high-speed ADC chip with a sampling frequency of up to 1MHz and a sampling accuracy of 16 bits. It is used to convert the analog signal output by the signal conditioning module into a digital signal and transmit it to the main control module. The data acquisition module supports multi-channel synchronous acquisition and can simultaneously acquire multiple types of signals such as voltage, current, temperature, and junction capacitance to ensure the synchronization of parameter detection.

6. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The main control module adopts an ARM Cortex-M4 core microcontroller and integrates a data processing unit, a parameter calibration unit, and a fault prediction unit. The data processing unit is used to analyze and calculate the acquired digital signals to obtain various performance parameters of the high-voltage rectifier diode under test, including reverse breakdown voltage, forward conduction voltage, leakage current, junction capacitance, thermal resistance coefficient, and reverse recovery time. The parameter calibration unit calibrates the detection data based on preset standard parameters and environmental compensation coefficients to eliminate the influence of temperature, humidity and electromagnetic interference on detection accuracy. The fault prediction unit uses historical detection data and a trend analysis algorithm to predict the trend of parameter changes. When the parameter approaches the threshold or an abnormal change occurs, an alarm signal is triggered.

7. The online detection system for all parameters of a high-voltage rectifier diode according to claim 1, characterized in that: The temperature compensation module is electrically connected to the temperature detection probe and the main control module. It is used to collect ambient temperature signals and transmit the temperature compensation coefficient to the main control module. The main control module corrects the detection data based on the temperature compensation coefficient to ensure the accuracy of the detection data under different ambient temperatures. The compensation range of the temperature compensation module is -40℃ to 180℃, which can adapt to the detection needs of different working environments.

8. The online full-parameter detection system for high-voltage rectifier diodes according to claim 1, wherein the data storage module adopts an SD card or Flash storage chip for storing detection parameters, calibration data, historical detection records and fault information, with a storage capacity of not less than 16GB, supporting data retention after power failure, facilitating subsequent data query, traceability and analysis; the display alarm module includes an LCD display screen and an audible and visual alarm, wherein the LCD display screen is used to display various detection parameters, device status and fault information in real time, and the audible and visual alarm is used to issue an alarm prompt when parameters are abnormal or faults occur, and the alarm mode can be manually set.

9. The online full-parameter testing system for high-voltage rectifier diodes according to claim 1, wherein the communication module supports one or more of RS485, Ethernet, and WiFi communication methods, and is used to realize communication between the testing system and the host computer and IoT platform, and can upload test data and fault information to the host computer in real time, facilitating remote monitoring, data management and batch device testing; the system also includes a power supply module, which provides a stable operating power supply for each module, and the power supply module supports wide voltage input (12-24V) and has overvoltage, overcurrent and short circuit protection functions.

10. A method for online detection of all parameters of a high-voltage rectifier diode, characterized in that: Includes the following steps, Step 1, System Initialization: The detection system is turned on, and the main control module performs a self-test on each module, checking the working status of the detection probe module, high voltage excitation module, signal conditioning module, and data acquisition module. If any abnormality is found, an alarm is triggered and the fault location is indicated. At the same time, preset standard parameters, calibration data, and temperature compensation coefficients are loaded to complete the system initialization. Step 2, Probe Connection and Parameter Setting: Connect the detection probe module to the high-voltage rectifier diode under test, ensuring a reliable connection; set the model, rated parameters (rated forward current, rated reverse voltage) and detection parameter thresholds of the device under test through the display alarm module or host computer. The main control module controls the high-voltage excitation module to adjust the excitation signal parameters according to the set parameters to adapt to the device under test. Step 3, Multi-parameter synchronous acquisition: The main control module controls the high-voltage excitation module to output a forward excitation signal, and acquires the forward conduction voltage (VF) and forward conduction current signals of the device under test through the detection probe module; it controls the high-voltage excitation module to output a reverse excitation signal, and acquires the reverse breakdown voltage (VBR) and leakage current (IR) signals; at the same time, it acquires the junction capacitance (Cj) signal through the junction capacitance detection probe, and acquires the junction temperature and ambient temperature signals of the device under test through the temperature detection probe; all acquired analog signals are filtered, amplified, and isolated by the signal conditioning module, and then transmitted to the data acquisition module to be converted into digital signals, and then transmitted to the main control module. Step 4, Data Processing and Calibration: The data processing unit of the main control module analyzes and calculates the acquired digital signals to obtain the original detection values ​​of various performance parameters; the parameter calibration unit calibrates the original detection values ​​based on the preset calibration data and the temperature compensation coefficient transmitted by the temperature compensation module to eliminate the influence of factors such as temperature and electromagnetic interference, and obtain accurate detection parameter values; at the same time, the thermal resistance coefficient (RθJC) is calculated based on the junction temperature and ambient temperature data, and the reverse recovery time (trr) is calculated based on the current change during forward and reverse excitation switching. Step 5, Performance Evaluation and Fault Prediction: The main control module compares the calibrated detection parameter values ​​with the preset thresholds to evaluate the performance status of the high-voltage rectifier diode under test. If all parameters are within the threshold range, the device is determined to be normal, and the detection parameters are displayed in real time. If any parameter exceeds the threshold, the device is determined to be abnormal, an audible and visual alarm is triggered, and the fault parameters and fault time are recorded. Meanwhile, the fault prediction unit analyzes the trend of parameter changes based on historical detection data. If the parameter shows an abnormal upward or downward trend and approaches the threshold, it will issue an early warning signal to prompt staff to handle it in a timely manner. Step 6, Data Storage and Transmission: The main control module stores accurate detection parameters, performance evaluation results, fault information, and historical detection records in the data storage module; at the same time, it uploads the detection data to the host computer or IoT platform in real time through the communication module, which facilitates remote monitoring, data query, and analysis; after the detection is completed, the detection can be stopped manually or an automatic detection cycle can be set to realize periodic online detection.

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