A wideband high-power microwave protection module design method based on field line coupling

Abstract

The application relates to a wideband high-power microwave protection module design method based on field line coupling, and belongs to the technical field of circuit simulation. The method comprises the following four steps: testing the response of a protection device under a nanosecond pulse; constructing an equivalent circuit model of a pulse source and the protection device; designing a protection module and simulating the characteristics of the protection module through a field line coupling method; and optimizing the protection module. The application has the following advantages: the field line coupling characteristics are considered, a protection module protection performance verification model is constructed, a cable coupling interference waveform is used to verify the protection performance of the protection module, and the accuracy of the protection performance simulation of the protection module is improved.

Description

Technical Field

[0001] This invention belongs to the field of circuit simulation technology, specifically relating to a design method for a broadband high-power microwave protection module based on field-line coupling. Background Technology

[0002] With the development of strong electromagnetic pulse (SEM) technology, electronic devices face increasingly harsh environments, making research on SEM protection technologies particularly important. SEM coupling paths are generally divided into radiation coupling and conducted coupling. For conducted coupling in a system, protection modules are typically used to protect downstream systems. Currently, the protection capabilities of these modules are generally verified through simulation and experimentation. Accurately representing the interference waveforms experienced by the protection module and improving the accuracy of simulations has become a key research focus. Therefore, a design method for broadband high-power microwave protection modules based on field-line coupling is needed to improve the accuracy of protection module protection effectiveness simulations.

[0003] The simulation accuracy of the protective effectiveness of the protection module depends on the pulse source parameter settings and the accuracy of the equivalent circuit model of the device. Currently, Chen Jin's project group at Xi'an University of Electronic Science and Technology has studied the response characteristics of the protective device under strong electromagnetic pulses and established the equivalent circuit model of the protective device. They used the constructed high-altitude nuclear electromagnetic pulse source model to simulate the protective effectiveness of the protection module. Li Xiangchao's project group at Nanjing University of Information Science and Technology studied the equivalent circuit model of the protective device and used an 8 / 20us impulse current generation loop and square wave simulation to analyze the energy coordination relationship of the protective device in the protection module. However, neither of them considered the interference waveform suffered by the protection module under field-line coupling, resulting in the problem of insufficient accuracy in the simulation of the protective effectiveness of the protection module. Summary of the Invention

[0004] This invention provides a design method for a broadband high-power microwave protection module based on field-line coupling, in order to solve the problem of low accuracy in the simulation of the protection effectiveness of existing protection modules.

[0005] The technical solution adopted by this invention includes the following steps:

[0006] Step 1: Test the response of the protection device under nanosecond-level pulses;

[0007] Step 2: Construct an equivalent circuit model of the pulse source and protection devices;

[0008] Step 3: Simulate the characteristics of the designed protection module using a field-circuit combined method;

[0009] Step 4: Optimize the protection module.

[0010] The step one of testing the response of the protection device under nanosecond-level pulses in this invention includes:

[0011] (1-1) Design and fabricate a special test fixture for protective devices;

[0012] (1-2) Test the waveform of the protection device under nanosecond pulse, import the waveform data into Matlab, and extract the response time, breakdown voltage and clamping voltage data of the protection device.

[0013] The second step of this invention, which involves constructing an equivalent circuit model of the pulse source and protection device, includes:

[0014] (2-1) Build a pulse source model in PSpice based on the rising edge, pulse width, and peak value data of the nanosecond-level pulse source waveform;

[0015] (2-2) Based on the response time, breakdown voltage, and clamping voltage data of the protective device extracted in step (1-2), a simulation model of the protective device is built, and the rationality of the simulation model of the protective device is verified in PSpice simulation.

[0016] The design of the protection module and the simulation of its characteristics using a field-line combined method in step three of this invention include:

[0017] (3-1) Establish a broadband high-power microwave cable coupling model in the CST cable studio, using broadband high-power microwave as the radiation source, and build a grounding circuit in the design studio. By placing probes, obtain the coupling voltage waveform of the cable under strong electromagnetic pulse irradiation.

[0018] (3-2) Import the simulation model of the protection device established in step (2-2) into the CST design studio, and complete the protection module circuit design through different combinations of protection devices;

[0019] (3-3) Using the coupling voltage waveform obtained in step (3-1) as a pulse source, build a protection module circuit in the CST design studio, measure the peak-to-peak voltage after passing through the protection module by placing probes, and calculate the protection effectiveness of the protection module.

[0020] The optimization of the protection module in step four of this invention includes:

[0021] The protective capabilities of different designed protective modules are determined by the protective effectiveness calculated in step (3-3). For protective modules that do not meet the protection requirements, the protective modules are optimized by modifying the device type, device parameters, and device combination protection. Step (3-3) is repeated to verify that the protective modules meet the protection requirements and then the design of the protective modules is completed.

[0022] The advantages of this invention are: it takes into account the field-line coupling characteristics, constructs a verification model for the protection effectiveness of the protection module, and uses cable coupling interference waveforms to verify the protection effectiveness of the protection module, thereby improving the accuracy of the simulation of the protection effectiveness of the protection module. Attached Figure Description

[0023] Figure 1 This is a flowchart of the present invention;

[0024] Figure 2 This is a schematic diagram of the test principle of the nanosecond-level pulse protection device of the present invention.

[0025] Figure 3 This is a schematic diagram of the simulation model verification principle of the protective device of this invention;

[0026] Figure 4 This is a simulation diagram illustrating the protective effectiveness of the protective module of this invention.

[0027] Figure 5 This invention provides a cable field coupling model under broadband high-power microwave conditions.

[0028] Figure 6 This invention provides a simulation model of cable circuits under broadband high-power microwave conditions.

[0029] Figure 7 This is a simulation diagram of the protection effectiveness of the three-level protection module under broadband high-power microwave conditions of the present invention;

[0030] Figure 8 This is a comparison diagram of voltage waveforms before and after the present invention is connected to the protection module;

[0031] Figure 9 This is a simulation diagram of the insertion loss of the protection module of the present invention. Detailed Implementation

[0032] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples.

[0033] See Figure 1 It includes the following steps:

[0034] Step 1: Test the response of the protection device under nanosecond-level pulses;

[0035] Step 2: Construct an equivalent circuit model of the pulse source and protection devices;

[0036] Step 3: Simulate the characteristics of the designed protection module using a field-circuit combined method;

[0037] Step 4: Optimize the protection module.

[0038] in:

[0039] Step 1: Test the response of the protection device under nanosecond-level pulses:

[0040] (1-1) Design and fabricate a special test fixture for protective devices;

[0041] (1-2) Test the waveform of the protection device under nanosecond-level pulses, import the waveform data into Matlab, and extract the response time, breakdown voltage, and clamping voltage data of the protection device. The test schematic diagram is shown below. Figure 2 As shown.

[0042] Step 2: Construct the equivalent circuit model of the pulse source and protection devices:

[0043] (2-1) Build a pulse source model in PSpice based on the rising edge, pulse width, and peak value data of the nanosecond-level pulse source waveform;

[0044] (2-2) Based on the response time, breakdown voltage, and clamping voltage data of the protective device extracted in step (1-2), a simulation model of the protective device is built. The rationality of the simulation model is verified in PSpice simulation. The verification principle diagram of the protective device simulation model is shown below. Figure 3 As shown.

[0045] Step 3: Design the protection module and simulate its characteristics using a field-to-circuit combined method:

[0046] (3-1) Establish a broadband high-power microwave cable coupling model in the CST cable studio, using broadband high-power microwave as the radiation source, and build a grounding circuit in the design studio. By placing probes, obtain the coupling voltage waveform of the cable under strong electromagnetic pulse irradiation.

[0047] (3-2) Import the simulation model of the protection device established in step (2-2) into the CST design studio, and complete the protection module circuit design through different combinations of protection devices;

[0048] (3-3) Using the coupled voltage waveform obtained in step (3-1) as the field line coupling interference source, a protection module circuit is built in the CST design studio. The peak-to-peak voltage after passing through the protection module is measured by placing probes, and the protection effectiveness of the protection module is calculated. The simulation schematic diagram of the protection effectiveness of the protection module is shown below. Figure 4 As shown.

[0049] Step 4: Optimize the protection module:

[0050] The protective capabilities of different designed protective modules are determined by the protective effectiveness calculated in step (3-3). For protective modules that do not meet the protection requirements, the protective modules are optimized by modifying the device type, device parameters, and device combination protection. Step (3-3) is repeated to verify that the protective modules meet the protection requirements and then the design of the protective modules is completed.

[0051] To enable those skilled in the art to better understand this invention, the following description uses the design process of a three-level protection module to further illustrate the invention.

[0052] Step 1: Test the response of the protection device under nanosecond-level pulses:

[0053] (1-1) Design and process a special test fixture for protective devices. Inside the housing, the gas discharge tube, varistor, and transient suppression diode are soldered to different PCBs for fixation. Coaxial connectors are used on both sides to ensure impedance matching.

[0054] (1-2) Extraction of device parameters under nanosecond pulses: The nanosecond pulses are generated by the EFT61004CG pulse generator. The output interface of the pulse source is connected to the test fixture via a coaxial line. The fixture contains the device under test. The fixture is connected to a 40dB attenuator via a coaxial line. The output interface of the attenuator is connected to an oscilloscope via a coaxial line. The response of the three devices is tested. The response waveform data is imported into Matlab to extract parameters such as response time, breakdown voltage, and clamping voltage.

[0055] Step 2: Construct the equivalent circuit model of the pulse source and protection devices:

[0056] (2-1) Pulse source model establishment: Based on the characteristics of nanosecond-level pulse source waveform, a pulse source model is built in PSpice. Based on the Marx principle and using the characteristics of the avalanche diode FMMT417, a nanosecond-level pulse source model with a rising edge of 5ns, a pulse width of 50ns, and adjustable amplitude is built.

[0057] (2-2) Establishment of protection device model: Based on the parameters such as response time and breakdown voltage extracted in step one, a simulation model of protection device is built and the pulse source model and the simulation model of protection device are connected in PSpice. The rationality of the simulation model of protection device is verified by simulation.

[0058] Step 3: Design the protection module and simulate its characteristics using a field-path combined approach:

[0059] (3-1) Extraction of electromagnetic field simulation results: A single-core wire coupling model was established in the CST cable studio, using broadband high-power microwave as the radiation source. In the design studio, the single-core wire was connected to a 50-ohm load and grounded, with probe P1 set up. The coupling voltage waveform of the cable under strong electromagnetic pulse irradiation was extracted. The cable field coupling model and circuit simulation model are as follows: Figure 5 , Figure 6 As shown.

[0060] (3-2) Design of protection module circuit: Import the equivalent circuit model of gas discharge tube, varistor and transient suppression diode established in step (2-2) into CST design studio, simulate the use of the device, design a fourth-order Butterworth circuit as the second level of the three-level protection module, and the limiter constitutes the third level of the protection module.

[0061] (3-3) Using the coupling voltage waveform obtained in step (3-1) as a pulse source, build a protection module circuit in the CST design studio. Measure the peak-to-peak voltage after passing through the protection module by placing probe P1, and calculate the protection effectiveness of the protection module. The simulation of the protection effectiveness of the protection module is as follows: Figure 7 As shown;

[0062] Step 4: Optimize the protection module:

[0063] The protection capability of different designed protection modules is determined by the protection effectiveness calculated in step (3-3). For protection modules that do not meet the protection requirements, optimization is performed by modifying device types, device parameters, and device combination protection. Step (3-3) is repeated to complete the design of the protection module. Simulation results show an insertion loss of 0.26 dB in the 0-1 MHz range, and the calculated protection effectiveness of the protection circuit is 28.5 dB, which meets the protection requirements. The simulation results are as follows. Figure 8 , Figure 9 As shown.

Claims

1. A design method for a broadband high-power microwave protection module based on field-line coupling, characterized in that, Includes the following steps: Step 1: Test the response of the protection device under nanosecond-level pulses; (1-1) Design and fabricate a special test fixture for protective devices; (1-2) Test the waveform of the protection device under nanosecond-level pulse, import the waveform data into Matlab, and extract the response time, breakdown voltage and clamping voltage data of the protection device; Step 2: Construct an equivalent circuit model of the pulse source and protection devices; (2-1) Build a pulse source model in PSpice based on the rising edge, pulse width, and peak value data of the nanosecond-level pulse source waveform; (2-2) Based on the response time, breakdown voltage, and clamping voltage data of the protective device extracted in step (1-2), a simulation model of the protective device is built, and the rationality of the simulation model of the protective device is verified in PSpice simulation. Step 3: Simulate the characteristics of the designed protection module using a field-circuit combined method; (3-1) Establish a broadband high-power microwave cable coupling model in the CST cable studio, using broadband high-power microwave as the radiation source, and build a grounding circuit in the design studio. By placing probes, obtain the coupling voltage waveform of the cable under strong electromagnetic pulse irradiation. (3-2) Import the simulation model of the protection device established in step (2-2) into the CST design studio, and complete the protection module circuit design through different combinations of protection devices; (3-3) Using the coupling voltage waveform obtained in step (3-1) as a pulse source, build a protection module circuit in the CST design studio, measure the peak-to-peak voltage after passing through the protection module by placing probes, and calculate the protection effectiveness of the protection module. Step 4: Optimize the protection module.

2. The design method for a broadband high-power microwave protection module based on field-line coupling according to claim 1, characterized in that, Step four, which optimizes the protection module, includes: The protective capabilities of different designed protective modules are determined by the protective effectiveness calculated in step (3-3). For protective modules that do not meet the protection requirements, the protective modules are optimized by modifying the device type, device parameters, and device combination protection. Step (3-3) is repeated to verify that the protective modules meet the protection requirements and then the design of the protective modules is completed.

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