Anti-interference pretest system suitable for large current injection and construction method

Abstract

The invention, which relates to the technical field of the BCI immunity test system, discloses a pre-test system suitable for high-current injection immunity, comprising a signal generator module, a power amplifier module, a current injection probe module, a monitoring and feedback module and a control and processing module. The large current injection immunity pre-test system can help an EMC engineer to quickly establish a large current injection (BCI) pre-test capability at a research and development site in the early development stage, effectively reduces the risk of product design, research and development, and has the advantages that the equipment investment of the site, the power amplifier and the current injection clamp is much smaller than that of a standard laboratory, and meanwhile, control software is not needed, so that the design and development efficiency is greatly improved. Therefore, the overall fixed asset investment of the pre-test system is very low, the research and development investment pressure on the majority of small and medium-sized enterprises is not large, the test result of the pre-test system is highly consistent with that of a standard test laboratory, and the pre-test system can be completely used for development test in the research and development stage.

Description

Technical Field

[0001] The present invention belongs to the technical field of BCI immunity test systems, and in particular relates to a system and a construction method for a large current injection immunity pre-test. Background Art

[0002] The existing large current injection (BCI) immunity test is particularly suitable for the RF interference immunity performance evaluation of electronic equipment in a small and confined space with complex cable laying environment. Therefore, it places extremely high demands on reliability and safety for products such as automotive electronic components, military standards, and avionics equipment, which are applied in harsh electromagnetic environments. Large current injection (BCI) can inject high-power RF energy into all cables within a wide frequency band, which is a great challenge for the immunity design of electronic equipment. At the same time, testing, system and solution verification all need to rely on standard commercial laboratory resources, which also has a great impact on R&D cost expenditure. Therefore, the risk of large current injection (BCI) in product development should not be underestimated, especially in the absence of large current injection (BCI) design experience and effective tools and methods. These products are applied in harsh electromagnetic environments and lack reliability and safety guarantees.

[0003] Traditional BCI immunity test systems often have some limitations. On the one hand, the test system is complex to build, and professionals need to spend a lot of time to configure and calibrate, resulting in low test efficiency. On the other hand, some existing test systems are insufficient in test accuracy and repeatability, and cannot meet the requirements for high-precision electronic equipment testing.

[0004] Therefore, it is necessary to develop a new type of large current injection immunity pre-test system and construction method to overcome the defects of the existing technology. Summary of the invention

[0005] The purpose of the present invention is to provide a large current injection immunity pre-test system and a construction method for addressing the problems of complex construction, high cost and insufficient test accuracy of the existing BCI immunity test system.

[0006] The present invention is achieved through the following technical solutions: A large current injection immunity pre-test system, comprising: Signal generator module, power amplifier module, current injection probe module, monitoring and feedback module, and control and processing module; The signal generator module is used to generate a test signal of a specific frequency and waveform; The power amplifier module receives the signal from the signal generator module and amplifies it to a sufficient power level so that a large current can be injected into the device under test through the current injection probe; this module has the characteristics of high gain and low distortion, and can ensure that the quality of the amplified signal meets the test requirements.

[0007] The current injection probe module is a key component for injecting large current into the device under test. It uses special design and materials, has good coupling efficiency and frequency response characteristics, and can accurately inject the large current signal output by the power amplifier into the key parts of the device under test, such as the power line and signal line, while minimizing the impact on the normal operation of the device under test.

[0008] The monitoring and feedback module is responsible for real-time monitoring of the magnitude and waveform of the injected current and the response of the device under test under the interference of the injected current. It feeds back the monitored information to the control and processing module through high-precision sensors and measurement circuits, so as to adjust and control the test process in real time.

[0009] The control and processing module is the core control unit of the entire test system; it receives information from the monitoring and feedback module, and controls the signal generator module and the power amplifier module according to the preset test parameters and algorithms, adjusts the frequency, amplitude and other parameters of the test signal, and processes and analyzes the test data to generate a test report.

[0010] Preferably, the signal generator module can generate various types of electromagnetic interference signals, including but not limited to sine waves, square waves, pulse waves, etc., and can accurately adjust the signal frequency within a wider frequency range to meet the testing requirements of different electronic devices.

[0011] Preferably, the power amplifier module adopts a small 100W radio frequency power amplifier, and the power amplifier output adopts a 3dB attenuator.

[0012] Preferably, the current injection probe module adopts a closed current injection clamp.

[0013] A method for building a large current injection immunity pre-test system includes the following steps: Step 1: Use the CISPR25 emission test bench as the BCI test bench without building a standard shielded room; Step 2: Build the signal generation module; Place the signal generator on a stable workbench, connect the power supply and ensure that it is well grounded; According to the operation manual of the signal generator, use the communication interface (such as USB, LAN, etc.) to connect it to the control computer to achieve remote control and parameter setting; Step 3: Build the power amplifier module; Install the power amplifier in a suitable heat dissipation environment to ensure that its heat dissipation channels are unobstructed to avoid performance degradation or damage due to overheating; Use high-quality RF cables to connect the output port of the signal generator to the input port of the power amplifier. Pay attention to matching and tightening the interfaces when connecting to reduce signal reflection and loss. A small 100W RF power amplifier is used, and a 3dB attenuator is used at the power amplifier output; Step 4: Install the current injection probe; Use a closed current injection clamp instead of an open current injection clamp, and fix the closed current injection clamp on a suitable test fixture or bracket to ensure that the probe position is stable and easy to operate; According to the wiring method of the tested cable, adjust the position and direction of the probe to make it well coupled with the tested cable; in the case of multiple cables, pay attention to the layout of the probe and its relative position to each cable to ensure uniform and effective current injection; Step 5: Set up monitoring and feedback module; Install monitoring equipment such as current sensors, voltage sensors and electromagnetic interference sensors, and place them close to the device under test and the current injection point to accurately obtain test data; when installing the sensors, pay attention to avoid external interference and use shielding measures.

[0014] Use data acquisition lines to connect the monitoring equipment to the control computer to ensure the stability and accuracy of data transmission. The sampling frequency of the data acquisition system should be set according to the frequency and change speed of the test signal, and generally high enough to capture the details of the signal.

[0015] Step 6: Configure the control and processing module; Install the test system control software on the control computer and configure the software according to the model and communication protocol of the selected equipment so that it can communicate normally with the signal generator, power amplifier and monitoring equipment; The test parameters are set in the software, including the waveform of the test signal, frequency range, amplitude variation range, gain control parameters of the power amplifier, etc. At the same time, data processing and analysis algorithms are established to process the monitoring data in real time and generate test reports.

[0016] Step 7: Manual calibration and testing operations can reduce investment in control equipment and software.

[0017] Compared with the prior art, the present invention has the following advantages: 1. The large current injection immunity pre-test system of the present invention can help EMC engineers quickly establish large current injection (BCI) pre-test capabilities at the R&D site in the early stages of development, effectively reducing product design and development risks. Since the equipment investment in the site, power amplifier and current injection clamp is much smaller than that in the standard laboratory, and no control software is required, the overall fixed asset investment in the pre-test system is very low, which does not put much pressure on R&D investment for small and medium-sized enterprises. Practice shows that the pre-test system is highly consistent with the test results of the standard test laboratory, and can be fully used for development testing in the R&D stage.

[0018] 2. The large current injection immunity pre-test system of the present invention has high test efficiency. Due to its modular design and advanced control algorithm, the system construction and configuration process is simple and fast, reducing the workload and test time of professionals.

[0019] 3. The large current injection immunity pre-test system of the present invention has high test accuracy and repeatability. Through high-precision signal generation technology, efficient power amplification technology, optimized current injection probe design and intelligent monitoring and feedback mechanism, the accuracy and reliability of the test results are effectively improved.

[0020] 4. The large current injection immunity pre-test system of the present invention has good adaptability. It can be applied to BCI immunity tests of electronic devices of different types and sizes, without a large number of adjustments and modifications for specific devices. Through the adaptive control algorithm, the system can automatically adjust the test parameters according to the characteristics of the device under test, reducing the test cost and cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The structural block diagram of a system suitable for large current injection immunity pre-test; Figure 2 The present invention is a flow chart of a method for building a large current injection immunity pre-test system. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1 See also Figure 1 , a system suitable for high current injection immunity pre-test, comprising: Signal generator module, power amplifier module, current injection probe module, monitoring and feedback module, and control and processing module; The signal generator module is used to generate a test signal of a specific frequency and waveform; The power amplifier module receives the signal from the signal generator module and amplifies it to a sufficient power level so that a large current can be injected into the device under test through the current injection probe; this module has the characteristics of high gain and low distortion, and can ensure that the quality of the amplified signal meets the test requirements.

[0024] The current injection probe module is a key component for injecting large current into the device under test. It uses special design and materials, has good coupling efficiency and frequency response characteristics, and can accurately inject the large current signal output by the power amplifier into the key parts of the device under test, such as the power line and signal line, while minimizing the impact on the normal operation of the device under test.

[0025] The monitoring and feedback module is responsible for real-time monitoring of the magnitude and waveform of the injected current and the response of the device under test under the interference of the injected current. It feeds back the monitored information to the control and processing module through high-precision sensors and measurement circuits, so as to adjust and control the test process in real time.

[0026] The control and processing module is the core control unit of the entire test system; it receives information from the monitoring and feedback module, and controls the signal generator module and the power amplifier module according to the preset test parameters and algorithms, adjusts the frequency, amplitude and other parameters of the test signal, and processes and analyzes the test data to generate a test report.

[0027] The signal generator module can generate various types of electromagnetic interference signals, including but not limited to sine waves, square waves, pulse waves, etc., and can accurately adjust the signal frequency within a wide frequency range to meet the testing requirements of different electronic devices.

[0028] The power amplifier module adopts a small 100W radio frequency power amplifier, and the power amplifier output adopts a 3dB attenuator.

[0029] The current injection probe module adopts a closed current injection clamp, which replaces the open current injection clamp to achieve more efficient coupling.

[0030] It should be noted that: if the budget is limited, there is no need to invest in current injection clamps and high-power broadband amplifiers. Using a voltage probe and a 5W low-power broadband amplifier to directly inject RF energy into the port circuit of the external cable can achieve 200mA BCI immunity evaluation. This pre-test method is convenient, fast and low-cost, and plays a very important role in early design analysis, identification and solution of BCI problems.

[0031] Embodiment 2 Based on the first embodiment, this embodiment proposes a method for building a large current injection immunity pre-test system. Figure 2 , including the following steps: Step 1: Use the CISPR25 emission test bench as the BCI test bench without building a standard shielded room; Step 2: Build the signal generation module; Place the signal generator on a stable workbench, connect the power supply and ensure that it is well grounded; According to the operation manual of the signal generator, use the communication interface (such as USB, LAN, etc.) to connect it to the control computer to achieve remote control and parameter setting; Step 3: Build the power amplifier module; Install the power amplifier in a suitable heat dissipation environment to ensure that its heat dissipation channels are unobstructed to avoid performance degradation or damage due to overheating; Use high-quality RF cables to connect the output port of the signal generator to the input port of the power amplifier. Pay attention to matching and tightening the interfaces when connecting to reduce signal reflection and loss. A small 100W RF power amplifier is used, and a 3dB attenuator is used at the power amplifier output; Step 4: Install the current injection probe; Use a closed current injection clamp instead of an open current injection clamp, and fix the closed current injection clamp on a suitable test fixture or bracket to ensure that the probe position is stable and easy to operate; According to the wiring method of the tested cable, adjust the position and direction of the probe to make it well coupled with the tested cable; in the case of multiple cables, pay attention to the layout of the probe and its relative position to each cable to ensure uniform and effective current injection; Step 5: Set up monitoring and feedback module; Install monitoring equipment such as current sensors, voltage sensors and electromagnetic interference sensors, and place them close to the device under test and the current injection point to accurately obtain test data; when installing the sensors, pay attention to avoid external interference and use shielding measures.

[0032] Use data acquisition lines to connect the monitoring equipment to the control computer to ensure the stability and accuracy of data transmission. The sampling frequency of the data acquisition system should be set according to the frequency and change speed of the test signal, and generally high enough to capture the details of the signal.

[0033] Step 6: Configure the control and processing module; Install the test system control software on the control computer and configure the software according to the model and communication protocol of the selected equipment so that it can communicate normally with the signal generator, power amplifier and monitoring equipment; The test parameters are set in the software, including the waveform of the test signal, frequency range, amplitude variation range, gain control parameters of the power amplifier, etc. At the same time, data processing and analysis algorithms are established to process the monitoring data in real time and generate test reports.

[0034] Step 7: Manual calibration and testing operations can reduce investment in control equipment and software.

[0035] This embodiment can help EMC engineers quickly establish large current injection (BCI) pre-test capabilities at the R&D site in the early stage of development, effectively reducing product design and development risks. Since the equipment investment in the site, power amplifier and current injection clamp is much smaller than that in the standard laboratory, and no control software is required, the overall fixed asset investment of the pre-test system is very low, which does not put much pressure on R&D investment for small and medium-sized enterprises. Practice shows that the pre-test system has a high consistency with the test results of the standard test laboratory and can be fully used for development testing in the R&D stage.

[0036] The testing process of the present invention: 1) Start the test system, the control and processing module sends instructions to the signal generator module to start generating test signals. After the signal is amplified by the power amplifier module, it is injected into the device under test through the current injection probe module.

[0037] 2) The monitoring and feedback module monitors the size and waveform of the injected current and the response of the device under test in real time. For example, the actual value of the injected current is measured by the current sensor and compared with the preset value. If the deviation exceeds the allowable range, the control and processing module is notified through the feedback mechanism to adjust the output of the power amplifier. At the same time, the device under test is monitored for abnormal working conditions, such as communication interruption, data error, etc.

[0038] 3) The control and processing module dynamically adjusts the test process based on the information provided by the monitoring and feedback module. If the device under test responds abnormally at a certain frequency, the control module will adjust the frequency of the signal generator to perform more detailed tests near the sensitive frequency, gradually increasing or decreasing the frequency step to accurately determine the immunity performance of the device under test.

[0039] 4) After the test is completed within the entire test frequency range, the control and processing module processes and analyzes the test data. Using data processing algorithms, the large amount of collected data is statistically analyzed, filtered, and feature extracted to generate a test report. The report lists in detail the immunity of the device under test at different frequencies, including the maximum current it can withstand, sensitive frequency points, and possible failure modes.

[0040] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions. The sentence "includes an element defined by ... does not exclude the existence of other identical elements in the process, method, article or device including the element".

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system suitable for large current injection immunity pre-test, characterized in that: include: Signal generator module, power amplifier module, current injection probe module, monitoring and feedback module, and control and processing module; The signal generator module is used to generate a test signal of a specific frequency and waveform; The power amplifier module receives the signal from the signal generator module and amplifies it to a sufficient power level so as to be able to inject a large current into the device under test through the current injection probe; The current injection probe module is a key component for injecting high current into the device under test; The detection and feedback module is responsible for real-time monitoring of the magnitude and waveform of the injected current and the response of the device under test under the interference of the injected current; The control and processing module is the core control unit of the entire test system; it receives information from the monitoring and feedback module, and controls the signal generator module and the power amplifier module according to the preset test parameters and algorithms, adjusts the frequency, amplitude and other parameters of the test signal, and processes and analyzes the test data to generate a test report.

2. A large current injection immunity pre-test system according to claim 1, characterized in that: The signal generator module can generate various types of electromagnetic interference signals, including but not limited to sine waves, square waves, pulse waves, etc., and can accurately adjust the signal frequency within a wide frequency range to meet the testing requirements of different electronic devices.

3. A large current injection immunity pre-test system according to claim 1, characterized in that: The power amplifier module adopts a small 100W radio frequency power amplifier, and the power amplifier output adopts a 3dB attenuator.

4. The system for pre-testing large current injection immunity according to claim 1, characterized in that: The current injection probe module adopts a closed current injection clamp.

5. A method for building a large current injection immunity pre-test system according to any one of claims 1 to 4, characterized in that: The steps include: Step 1: Use the CISPR25 emission test bench as the BCI test bench without building a standard shielded room; Step 2: Build the signal generation module; Place the signal generator on a stable workbench, connect the power supply and ensure that it is well grounded; According to the operation manual of the signal generator, use the communication interface to connect it to the control computer to achieve remote control and parameter setting; Step 3: Build the power amplifier module; Install the power amplifier in a suitable heat dissipation environment to ensure that its heat dissipation channels are unobstructed to avoid performance degradation or damage due to overheating; Use high-quality RF cables to connect the output port of the signal generator to the input port of the power amplifier. Pay attention to matching and tightening the interfaces when connecting to reduce signal reflection and loss. Among them, a small 100W RF power amplifier is used, and a 3dB attenuator is used at the power amplifier output; Step 4: Install the current injection probe; Use a closed current injection clamp instead of an open current injection clamp, and fix the closed current injection clamp on a suitable test fixture or bracket to ensure that the probe position is stable and easy to operate; According to the wiring method of the cable under test, adjust the position and direction of the closed current injection clamp to ensure good coupling with the cable under test; Step 5: Set up monitoring and feedback module; Install monitoring equipment such as current sensors, voltage sensors, and EMI sensors close to the device under test and the current injection point to accurately obtain test data; Use data acquisition lines to connect the monitoring equipment to the control computer to ensure the stability and accuracy of data transmission; Step 6: Configure the control and processing module; Install the test system control software on the control computer and configure the software according to the model and communication protocol of the selected equipment so that it can communicate normally with the signal generator, power amplifier and monitoring equipment; Step 7: Manual calibration and testing operations can reduce investment in control equipment and software.

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