A continuous surge current impact life test device and test method for a rectifier bridge

Abstract

The present invention solves the problem that the existing rectifier bridge surge test device cannot perform continuous surge testing, and provides a continuous surge current impact life test device for a rectifier bridge. By providing a three-phase power supply circuit with three-phase low voltage and large current, it is used to test the continuous surge resistance of the rectifier bridge. On the one hand, it saves energy, and on the other hand, it also improves safety. Finally, the breakdown of the diode due to the reverse withstand voltage problem can be completely eliminated, which is conducive to the analysis of other damage mechanisms of the diode.

Description

Technical Field

[0001] The invention relates to the technical field of rectifier bridges, in particular to a continuous surge current impact life test device for rectifier bridges. Background Art

[0002] Due to the surge voltage and surge current generated in the circuit when the switch is turned on and off or when lightning strikes, it is necessary to verify whether the performance of the device under test is affected by the high-energy disturbance generated on the power supply and interconnection lines through a surge impact test project. The existing test method is to use a lightning surge generator to simulate the switching transient and lightning transient phenomena. The device uses a sinusoidal half-wave large current of a set frequency to impact the device under test, such as the content shown in the patent with the authorization announcement number CN104865513B. However, in the existing surge test circuit, only a single surge current can be tested. Although the limit surge current value of the device can be detected, the performance of the device against continuous surge current is unknown. In actual use, there will be continuous surge current in the circuit at the application end and the current value generated by the surge is small; therefore, a rectifier bridge life test device and test method capable of performing continuous surge current testing is required. Summary of the invention

[0003] The purpose of the present invention is to solve the deficiencies of the prior art and provide a continuous surge current impact life test device for a rectifier bridge.

[0004] In order to solve the above problems, the present invention adopts the following technical solutions:

[0005] A continuous surge current impact life test device for a rectifier bridge comprises a three-phase power supply circuit and a test circuit, wherein the three-phase power supply circuit is electrically connected to the test circuit; the three-phase power supply circuit comprises a three-phase low-voltage and high-current power supply for providing three-phase low-voltage and high-current; the test circuit comprises a DC regulated power supply, a control board, a large-capacity filter electrolytic and an adjustable resistance load, and the control board comprises a signal acquisition analog amplifier, Waveform transformation and analysis as well as test data communication transmission; wherein the three-phase current output by the three-phase power supply circuit is respectively connected to the three input interfaces of the rectifier bridge to be tested, the positive and negative electrodes of the output interface of the rectifier bridge are respectively connected to the two ends of the filter electrolytic, and the filter electrolytic is also connected in parallel with the adjustable resistance load; the adjustable resistance load is also connected to the control board, and the size of the adjustable resistance load is adjusted by the control board; the DC regulated power supply is connected to the filter electrolytic through an anti-backflow diode for soft starting; the control board includes three AC voltage probes, three AC current probes, six groups of differential voltage probes, a DC bus current probe and a DC bus current probe; the three AC voltage probes are respectively connected to the three-phase output ends of the three-phase power supply circuit, and the three AC current probes are respectively connected to the three-phase output ends of the series three-phase power supply circuit; the six groups of differential voltage probes are respectively connected to the two ends of the six rectifier diodes in the rectifier bridge; the DC bus current probe is connected in series to the output end of the rectifier bridge, and the DC bus voltage probe is connected to the output positive and negative poles of the rectifier bridge.

[0006] Furthermore, the three-phase power supply circuit includes a three-phase power supply, a three-phase high-speed circuit breaker and a three-phase isolation transformer; wherein the three-phase power supply is connected to the three-phase isolation transformer through the three-phase high-speed circuit breaker; the three-phase high-speed circuit breaker is also connected to the output port of the control board.

[0007] Furthermore, the three-phase power supply outputs 380V AC power, and the transformation ratio of the three-phase isolation transformer is 380:36.

[0008] Furthermore, the filter electrolysis includes a plurality of electrolytic capacitors connected in parallel; wherein the positive electrodes of the electrolytic capacitors are connected to the positive output interface of the rectifier bridge to be tested, and the negative electrodes of the electrolytic capacitors are connected to the negative output interface of the rectifier bridge to be tested.

[0009] Furthermore, the control board includes an analog signal acquisition module (a three-phase voltage and current signal acquisition module, a differential measurement module at both ends of a diode, a bus voltage and current signal acquisition module, and a signal processing module), an electric energy ADC acquisition module, a high-speed ADC acquisition module, an MCU central processing module, a high-speed storage RAM module, a ROM storage module, a communication module, and a display module; wherein the MCU central processing module is respectively connected to the RAM storage module, the ROM storage module, the high-speed ADC acquisition module, the signal processing module, the communication module, and the display module; the analog signal acquisition module is also connected to the electric energy ADC acquisition module and the high-speed ADC acquisition module, the analog signal acquisition module transmits the AC voltage signal and AC current signal of each phase in the three-phase line to the electric energy ADC acquisition module, and the analog signal acquisition module transmits the voltage at both ends of the rectifier diode and the bus current signal to the high-speed ADC acquisition module; the high-speed ADC acquisition module is also connected to the high-speed RAM storage module to complete direct high-speed waveform storage; the analog signal acquisition module includes a three-phase voltage and current signal acquisition module, a differential measurement module at both ends of a diode, a bus voltage and current signal acquisition module, and a signal processing module.

[0010] Furthermore, the communication module includes a WIFI module, a USB module, a CAN module and a network module.

[0011] Furthermore, the processing module includes an STM32 H7 microprocessor, and the processing module is also provided with a debug interface.

[0012] Furthermore, a contactor for switching is provided between the filter electrolysis and the adjustable resistance load.

[0013] A continuous surge current impact life test method for a rectifier bridge, the test method is based on the above-mentioned test device, and the test method comprises the following steps:

[0014] Step 1: Turn on the DC regulated power supply, and use the DC regulated power supply to charge the filter electrolysis module;

[0015] Step 2: Detect the voltage V1 at both ends of the filter electrolysis until the value of the voltage V1 is consistent with the output voltage value set by the DC regulated power supply, indicating that the filter electrolysis module has completed charging and proceeds to the next step;

[0016] Step 3: Close the three-phase high-speed circuit breaker to connect the three-phase power supply to the three-phase isolation transformer. The three-phase isolation transformer outputs low voltage and high current after transformation;

[0017] Step 4: Close the contactor to connect the rectifier bridge to the adjustable resistance load as the load;

[0018] Step 5: The control board collects the voltage and current data of each phase between the three-phase isolation transformer and the rectifier bridge, the differential voltage of the rectifier diode, and the rectified DC bus voltage and DC bus current;

[0019] Step 6: The control board determines whether there is any abnormality in the collected voltage and current data; if there is an abnormality, the three-phase high-speed circuit breaker is controlled to quickly cut off the connection between the three-phase power supply and the three-phase isolation transformer, and the data waveform at the abnormal moment is recorded; otherwise, the voltage and current data are observed and recorded until the test is completed.

[0020] Furthermore, the voltage output by the three-phase power supply in step 3 is a 50 Hz sinusoidal wave voltage.

[0021] The beneficial effects of the present invention are:

[0022] By providing a three-phase low-voltage three-phase power supply circuit, it is used to test the rectifier bridge's ability to resist continuous surges, which saves energy efficiency on the one hand, improves safety on the other hand, and finally facilitates the analysis of the fault circuit without directly breaking down the diode;

[0023] By setting up the control board, various data in the test circuit are collected and analyzed to obtain a more accurate test of the rectifier bridge's ability to resist continuous surges;

[0024] By setting up a three-phase high-speed circuit breaker and a three-phase isolation transformer, when an abnormality occurs during the surge test, the three-phase power supply circuit can be quickly cut off to prevent greater damage to the device under test;

[0025] By setting the module connection relationship in the control board, the MCU central processor can analyze the current and voltage signals, and can also store and display the data to achieve data visualization;

[0026] Through the testing method, the ability of the rectifier bridge to resist continuous surges is analyzed, and the performance of all aspects of the rectifier bridge is more comprehensively understood. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the overall circuit of Example 1;

[0028] Figure 2 This is a functional block diagram of the control panel of Example 1;

[0029] Figure 3 Schematic diagram of surge test voltage and current waveforms of Example 1. DETAILED DESCRIPTION

[0030] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0031] It should be noted that the illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention. The figures only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated. Example

[0032] like Figure 1 As shown, a continuous surge current impact life test device for a rectifier bridge comprises a three-phase power supply circuit and a test circuit, wherein the three-phase power supply circuit is electrically connected to the test circuit; the three-phase power supply circuit comprises a three-phase low-voltage and high-current power supply for providing three-phase low-voltage and high-current; the test circuit comprises a DC voltage-stabilized power supply, a control board, a large-capacity filter electrolysis and an adjustable resistance load; the control board comprises several parts including signal acquisition analog amplification, waveform conversion and analysis and test data communication transmission; wherein the three-phase current output by the three-phase power supply circuit is respectively connected to the three input interfaces of the rectifier bridge to be tested, the positive and negative electrodes of the output interface of the rectifier bridge are respectively connected to the two ends of the filter electrolysis, and the filter electrolysis module is also connected in parallel with the adjustable resistance load; the adjustable resistance load is also connected to the control board, and the size of the adjustable resistance load is adjusted by the control board, and the function of the adjustable resistance load is to adjust the continuous surge current The DC regulated power supply is connected to the filter electrolytic via an anti-backflow diode, and the positive output of the DC regulated power supply is connected to the A pole of the anti-backflow diode; in this example, the output voltage of the DC regulated power supply is set to 60V, and the output current is set to 10A; the control board includes three AC voltage probes, three AC current probes, six groups of differential voltage probes, and a DC current probe and a DC current probe; the three AC voltage probes are respectively connected to the three-phase output ends of the three-phase power supply circuit, and the three AC current probes are respectively connected to the three-phase output ends of the series three-phase power supply circuit; the six groups of differential voltage probes are respectively connected to the two ends of the six rectifier diodes in the rectifier bridge to realize the voltage detection on each rectifier diode; the DC bus current probe is connected in series to the output end of the rectifier bridge, and the DC bus voltage probe is connected to the output positive and negative poles of the rectifier bridge to obtain the rectified bus forward current and forward voltage.

[0033] The three-phase power supply circuit includes a three-phase power supply, a three-phase high-speed circuit breaker and a three-phase isolation transformer; wherein the three-phase power supply is connected to the three-phase isolation transformer through the three-phase high-speed circuit breaker; the three-phase high-speed circuit breaker is also connected to the output port of the control board. In this example, the AC voltage probe and the AC current probe are arranged on the secondary side of the three-phase isolation transformer, and the current and voltage of each phase after the transformation by the three-phase isolation transformer are obtained through three AC voltage probes and three AC current probes. In this example, the three-phase power supply outputs 380V AC, and the transformation ratio of the three-phase isolation transformer is 380:36, that is, the AC voltage after the transformation output is only about 36V. Because the simulated surge current in the circuit has little to do with the voltage originally transmitted in the circuit, a lower voltage is used. When a reverse surge occurs, the reverse surge voltage caused by the lower line voltage is smaller, which is not easy to cause the rectifier diode to break down, and can better analyze the faults in the rectifier bridge. In traditional test devices, the rectifier diode in the rectifier bridge will usually directly cause the tube to explode after failing to resist the reverse surge, which is not conducive to subsequent analysis; in addition, the lower voltage can also reduce energy consumption and improve operational safety. The results of the surge test are as follows: Figure 3 As shown by Figure 3 It can be seen that the reverse surge voltage is low and is not likely to cause instantaneous breakdown of the PN junction.

[0034] The filter electrolysis module includes several electrolytic capacitors connected in parallel; wherein the positive electrodes of the electrolytic capacitors are connected to the positive output interface of the rectifier bridge to be tested, and the negative electrodes of the electrolytic capacitors are connected to the negative output interface of the rectifier bridge to be tested. In this example, the capacity specification of the electrolytic capacitor is 100mF / 100V; the number of electrolytic capacitors is 10. A contactor for switching is also provided between the filter electrolysis and the adjustable resistance load.

[0035] like Figure 2As shown, the control board includes an analog signal acquisition module, an electric energy ADC acquisition module, a high-speed ADC acquisition module, an MCU central processing module, a high-speed storage RAM module, a ROM storage module, a communication module, and a display module; wherein the MCU central processing module is respectively connected to the RAM storage module, the ROM storage module, the high-speed ADC acquisition module, the signal processing module, the communication module, and the display module; the analog signal acquisition module is also connected to the electric energy ADC acquisition module and the high-speed ADC acquisition module, the analog signal acquisition module transmits the AC voltage signal and AC current signal of each phase in the three-phase line to the electric energy ADC acquisition module, and the analog signal acquisition module transmits the voltage at both ends of the rectifier diode and the bus current signal to the high-speed ADC acquisition module; the high-speed ADC acquisition module is also connected to the high-speed RAM storage module to complete direct high-speed waveform storage. The analog signal acquisition module includes a three-phase voltage and current signal acquisition module, a differential measurement module at both ends of the diode, a bus voltage and current signal acquisition module, and a signal processing module. The electric energy ADC acquisition module uses the ADE9000 integrated chip to monitor and analyze the AC voltage and AC current of each phase. The high-speed ADC acquisition module uses the AD6655 integrated chip to analyze the reverse recovery characteristic curve of the diode. The storage module includes RAM and ROM, of which ROM uses eMMC storage to store data for easy review. The communication module includes a WIFI module, a USB module, a CAN module, and a network module. The processing module includes an STM32 H7 microprocessor, and the processing module is also provided with a debug interface.

[0036] A continuous surge current impact life test method for a rectifier bridge, the test method is based on the above-mentioned test device, and the test method comprises the following steps:

[0037] Step 1: Turn on the DC regulated power supply, and use the DC regulated power supply to charge the filter electrolytic;

[0038] Step 2: Detect the voltage V1 at both ends of the filter electrolysis module until the value of the voltage V1 is consistent with the output voltage value set by the DC regulated power supply, indicating that the filter electrolysis has completed charging and proceeds to the next step;

[0039] Step 3: Close the three-phase high-speed circuit breaker to connect the three-phase power supply to the three-phase isolation transformer. The three-phase isolation transformer outputs low voltage and high current after transformation;

[0040] Step 4: Close the contactor to connect the rectifier bridge to the adjustable resistance load as the load;

[0041] Step 5: The control board collects the voltage and current data of each phase between the three-phase isolation transformer and the rectifier bridge, the differential voltage of the rectifier diode, and the rectified DC voltage and DC current;

[0042] Step 6: The control board determines whether there is any abnormality in the collected voltage and current data; if there is an abnormality, the three-phase high-speed circuit breaker is controlled to quickly cut off the connection between the three-phase power supply and the three-phase isolation transformer, and the waveform when the abnormality occurs is recorded; otherwise, the voltage and current data are observed and recorded until the test is completed.

[0043] The voltage output by the three-phase power supply in step 3 is a 50 Hz sinusoidal wave voltage.

[0044] The difference between this embodiment and the existing single surge tester is that in this example, the test surge current is continuous, the six diodes in the three-phase rectifier bridge under test are tested simultaneously, and the waveform data is completely recorded in real time, and the waveform data directly reflects the essence of the diode device characteristics; in contrast, the single surge tester can only test a single surge current, a single current waveform and reverse withstand voltage data, and the waveform is difficult to record at the moment of diode surge current breakdown. In comparison, this example can record the continuous surge current waveform and the forward voltage drop waveform and reverse voltage waveform of each diode in real time, and store the waveform at the moment of diode breakdown for subsequent analysis.

[0045] During the implementation process, a three-phase low-voltage and high-current power supply device is provided to test the continuous surge capability of the rectifier bridge, which saves energy efficiency on the one hand, improves safety on the other hand, and finally facilitates the failure analysis of the rectifier bridge to eliminate the direct breakdown of the diode due to voltage resistance problems; the various data in the test rectifier bridge are analyzed after the control board signal acquisition and transformation, so as to obtain a more accurate test of the continuous surge resistance of the rectifier bridge. It should be noted that the existing analysis method is used for the analysis of the data; by setting a three-phase high-speed circuit breaker and a three-phase isolation transformer, on the one hand, when an abnormality occurs in the surge test, the three-phase power supply circuit is quickly cut off to prevent greater damage to the rectifier bridge, and on the other hand, the test voltage is reduced; by setting the module connection relationship of the control board, the control board can analyze various signals, and can also store and display data, and visualize the data; through the test method, the ability of the rectifier bridge to resist continuous surges is analyzed, and a more comprehensive understanding of the various aspects of the performance of the rectifier bridge is obtained.

[0046] The above description is only a specific example of the present invention and does not constitute any limitation to the present invention. It is obvious that for professionals in this field, after understanding the content and principle of the present invention, various modifications and changes in form and details may be made without departing from the principle and structure of the present invention, but these modifications and changes based on the idea of ​​the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A continuous surge impact life test method for a rectifier bridge, based on a continuous surge impact life test device, the test device comprises a three-phase power supply circuit and a test circuit, wherein the three-phase power supply circuit is electrically connected to the test circuit; the three-phase power supply circuit comprises a three-phase low-voltage and high-current power supply for providing three-phase low-voltage and high-current; the test circuit comprises a control board, a DC regulated power supply, a large-capacity filter electrolytic module and an adjustable resistance load, the control board comprises a signal acquisition analog amplifier, Waveform transformation and analysis as well as test data communication transmission; wherein the three-phase current output by the three-phase power supply circuit is respectively connected to the three input interfaces of the rectifier bridge to be tested, and the positive and negative electrodes of the output interface of the rectifier bridge are respectively connected to the two ends of the filter electrolysis module, and the filter electrolysis module is also connected in parallel with the adjustable resistance load; the adjustable resistance load is also connected to the control board, and the size of the adjustable resistance load is adjusted by the control board; the DC regulated power supply is connected to the filter electrolysis module through an anti-backflow diode for soft starting at startup; the signal acquisition includes three AC voltage probes, three AC current probes, six groups of differential voltage probes, and a DC bus voltage probe and a DC bus current probe; the three AC voltage probes are respectively connected to the three-phase output ends of the three-phase power supply circuit, and the three AC current probes are respectively connected to the three-phase output ends of the series three-phase power supply circuit; the six groups of differential voltage probes are respectively connected to the two ends of the six rectifier diodes in the rectifier bridge; the DC bus current probe is connected in series to the output end of the rectifier bridge, and the DC bus voltage probe is connected to the output positive and negative poles of the rectifier bridge; It is characterized in that The testing method comprises the following steps: Step 1: Turn on the DC regulated power supply, and use the DC regulated power supply to charge the filter electrolysis module; Step 2: Detect the voltage V1 at both ends of the filter electrolysis module until the value of the voltage V1 is consistent with the output voltage value set by the DC regulated power supply, indicating that the filter electrolysis module has completed charging and proceeds to the next step; Step 3: Close the three-phase high-speed circuit breaker to connect the three-phase power supply to the three-phase isolation transformer. The three-phase isolation transformer outputs low voltage and high current after transformation; Step 4: Close the contactor to connect the rectifier bridge to the adjustable resistance load as the load; Step 5: The control board collects the voltage and current data of each phase between the three-phase isolation transformer and the rectifier bridge, the differential voltage of the rectifier diode, and the rectified DC bus voltage and DC bus current; Step 6: The control board determines whether there is any abnormality in the collected voltage and current data; if there is an abnormality, the three-phase high-speed circuit breaker is controlled to quickly cut off the connection between the three-phase power supply and the three-phase isolation transformer, and the data waveform at the time of the abnormality is recorded; otherwise, the voltage and current data are kept observed and recorded until the test is completed.

2. The continuous surge impact life test method of a rectifier bridge according to claim 1, characterized in that: The voltage output by the three-phase power supply in step 3 is a 50 Hz sinusoidal wave voltage.

3. The continuous surge impact life test method of a rectifier bridge according to claim 1, characterized in that: The three-phase power supply circuit includes a three-phase power supply, a three-phase high-speed circuit breaker and a three-phase isolation transformer; wherein the three-phase power supply is connected to the three-phase isolation transformer through the three-phase high-speed circuit breaker; the three-phase high-speed circuit breaker is also connected to the output port of the control board.

4. The continuous surge impact life test method of a rectifier bridge according to claim 3 is characterized in that: The three-phase power supply outputs 380V AC power, and the transformation ratio of the three-phase isolation transformer is 380:

36.

5. The continuous surge impact life test method of a rectifier bridge according to claim 1, characterized in that: The filter electrolysis module includes a plurality of electrolytic capacitors connected in parallel; wherein the positive electrodes of the electrolytic capacitors are connected to the positive output interface of the rectifier bridge to be tested, and the negative electrodes of the electrolytic capacitors are connected to the negative output interface of the rectifier bridge to be tested.

6. The continuous surge impact life test method of a rectifier bridge according to claim 3, characterized in that: The control board includes an analog signal acquisition module, an electric energy ADC acquisition module, a high-speed ADC acquisition module, an MCU central processing module, a high-speed storage RAM module, a ROM storage module, a communication module and a display module; The MCU central processing module is connected to the RAM storage module, ROM storage module, high-speed ADC acquisition module, signal processing module, communication module and display module respectively; the analog signal acquisition module is also connected to the electric energy ADC acquisition module and the high-speed ADC acquisition module, the analog signal acquisition module transmits the AC voltage signal and AC current signal of each phase in the three-phase line to the electric energy ADC acquisition module, and the analog signal acquisition module transmits the voltage across the rectifier diode and the bus current signal to the high-speed ADC acquisition module; the high-speed ADC acquisition module is also connected to the high-speed RAM storage module to complete direct high-speed waveform storage; the analog signal acquisition module includes a three-phase voltage and current signal acquisition module, a differential measurement module across the diode, a bus voltage and current signal acquisition module and a signal processing module.

7. The continuous surge impact life test method of a rectifier bridge according to claim 6, characterized in that: The communication module includes a WIFI module, a USB module, a CAN module and a network module.

8. The continuous surge impact life test method of a rectifier bridge according to claim 6, characterized in that: The processing module includes an STM32 H7 microprocessor, and the processing module is also provided with a debug interface.

9. The continuous surge impact life test method of a rectifier bridge according to claim 1, characterized in that: A contactor for switching is also provided between the filter electrolysis module and the adjustable resistance load.

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