A nanosecond high-voltage pulse generator and a high-voltage probe rise time tracing method

Abstract

The present invention discloses a nanosecond high-voltage pulse generator and a method for tracing the rise time of a high-voltage probe. The method comprises a system power supply, an auxiliary power supply, a single-chip microcomputer, a display control module, a direct current high-voltage drive circuit, a direct current high-voltage switch circuit, a discharge protection circuit, and a feedback protection circuit. The method can generate an adjustable high-voltage pulse with a rise time tr=1.4ns and an amplitude of up to 3kV. The high-voltage probe is attenuated and then connected to an oscilloscope with a bandwidth greater than twice that of the high-voltage probe to acquire a complete waveform. The rise time t is measured using the measurement function of the oscilloscope. If t=tr×(1±10%)ns, it is considered that the measurement system composed of the oscilloscope and the high-voltage probe can accurately acquire pulse signals with a rise time t≥tr (ns), thereby proving that the bandwidth B of the high-voltage probe is ≥350 / tr, thereby achieving traceability of the bandwidth of the high-voltage probe.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage pulse output, and in particular to a nanosecond-level high-voltage pulse generator and a method for tracing the rise time of a high-voltage probe. Background Art

[0002] In recent years, as high-voltage pulse power supplies have been widely used in various fields such as industry, medical treatment, military, and measurement, the technological development in these fields has placed increasingly higher requirements on high-voltage pulse power supplies. Accurate measurement of waveform parameters such as rise time, pulse width, and amplitude has become a key factor restricting the development of high-voltage pulse power supply research and development technology.

[0003] Currently, the common method for measuring high-voltage pulse waveform parameters is to use a measurement system composed of a high-voltage probe and an oscilloscope to acquire the waveform and then perform measurements. To ensure the accuracy of the measurement results, the acquisition system must first have sufficient bandwidth to capture the generated high-voltage pulse without distortion. This necessitates calibration of the measurement system's rise time. Current rise time calibration uses a 1V fast-edge generator, which is inconsistent with the actual measurement method of acquiring the high-voltage pulse after attenuation. This results in poor measurement repeatability, large uncertainty, and difficulty in ensuring measurement accuracy when measuring the rise time of high-voltage pulse signals. Summary of the Invention

[0004] The purpose of the present invention is to provide a nanosecond high-voltage pulse generator and a high-voltage probe rise time tracing method, which can generate high-voltage pulses with a rise time of 1.4ns and an amplitude of 3kV, solves the calibration problem of oscilloscopes and high-voltage probes in actual working conditions, effectively solves the value tracing problem of high-voltage probes in my country, and solves the difficult problem that restricts the development of high-voltage pulse sources.

[0005] The technical solution adopted in the present invention is:

[0006] A nanosecond high-voltage pulse generator comprises a system power supply, an auxiliary power supply, a single-chip microcomputer, a display control module, a DC high-voltage drive circuit, a DC high-voltage switch circuit, a discharge protection circuit and a feedback protection circuit; the system power supply is connected to the auxiliary power supply, the single-chip microcomputer and the DC high-voltage drive circuit and supplies power; the single-chip microcomputer is respectively connected to the display control module, the DC high-voltage drive circuit, the DC high-voltage switch circuit and the feedback protection circuit; the output end of the auxiliary power supply is connected to the power supply end of the DC high-voltage switch circuit, the start-controlled end of the DC high-voltage switch circuit is connected to the output end of the DC high-voltage drive circuit, the DC high-voltage switch circuit is connected to the single-chip microcomputer via the feedback protection circuit, and the DC high-voltage switch circuit is also connected to the discharge protection circuit.

[0007] The DC high-voltage drive circuit includes a TTL signal drive module, a controlled end of the TTL signal drive module is connected to the single-chip microcomputer, and an output end of the TTL signal drive module is connected to the open controlled end of the DC high-voltage switch circuit.

[0008] The DC high-voltage switching circuit includes a PWM modulation drive module, a PWM high-voltage pre-stage drive module, a rectifier detection module, a rectifier voltage doubler module, a high-voltage switch module and a DC high-voltage pulse output module, which are electrically connected in sequence. The PWM high-voltage pre-stage drive module, the rectifier detection module, the rectifier voltage doubler module and the high-voltage switch module are respectively connected to the feedback protection circuit, the rectifier detection module is connected to the single-chip microcomputer through the detection module, the rectifier voltage doubler module is connected to the discharge protection circuit, and the controlled end of the high-voltage switch module is connected to the output end of the TTL signal drive module.

[0009] The high-voltage switch module consists of a high-voltage pulse module and a peripheral circuit. The peripheral circuit includes a coupling resistor, a buffer capacitor, a current limiting resistor, an RC absorption circuit and a feedback resistor. The output end of the TTL signal driving module is connected to the signal receiving port of the high-voltage pulse module through a coupling resistor, and the output signal of the TTL signal driving module is used as a trigger signal for the high-voltage pulse module; the auxiliary power supply is connected to the power supply port of the high-voltage pulse module through a buffer capacitor; the alarm feedback port of the high-voltage pulse module is connected to the alarm end of the single-chip microcomputer, the high-voltage input end of the high-voltage pulse module is connected to the high-voltage source through a current limiting resistor, the high-voltage pulse module is also connected to the RC absorption circuit, and the high-voltage pulse module outputs a pulse DC signal through the feedback resistor.

[0010] The high-voltage pulse module includes a photoelectric isolator, an operational amplifier, a MOSFET driver tube, and multiple groups of parallel synchronous adjustable pulse output circuits. Each group of synchronous adjustable pulse output circuits includes a circuit consisting of a pulse transformer, a resonance module, a protection module, a MOSFET power tube, and an adjustable resistor connected in series. The signal receiving end of the photoelectric isolator is connected to the output end of the TTL signal driver module, the output end of the photoelectric isolator is connected to the inverting input end of the operational amplifier, the in-phase input end and output end of the operational amplifier are both connected to the gate of the MOSFET driver tube, and the drain of the MOSFET driver tube is connected to the primary side of the pulse transformer of the first group of synchronous adjustable pulse output circuits. The drain of the Mosfet driving tube is also connected to the power supply end of the auxiliary power supply. The secondary side of the pulse transformer of each group of synchronous adjustable pulse output circuits is connected to the gate of the Mosfet power tube through the resonance module and the protection module respectively. The drain of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the DC high-voltage power supply end, and the source of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the drain of the next group of Mosfet power tubes. Multiple Mosfet power tubes are connected in sequence, and the source of the Mosfet power tube of the last group of synchronous adjustable pulse output circuits is used as the output end to output an adjustable pulse signal.

[0011] A method for tracing the rise time of a high-voltage probe based on a nanosecond-level high-voltage pulse generator comprises the following steps:

[0012] A: Connect the output of the high-voltage pulse generator to the power supply of the high-voltage probe. Then, connect the attenuated high-voltage probe to an oscilloscope with a bandwidth twice that of the high-voltage probe to form a measurement system and acquire the complete waveform.

[0013] B: Use the oscilloscope's measurement function to measure the rise time of the high-voltage probe t , if the rise time t = t r × (1 ± 10%) ns, where t r is the rise time of the high voltage pulse generator, using the formula calculate;

[0014] In the formula, is the impedance value of the resonant module and the resistance R of the MOSFET power tube itself g sum;

[0015] C gd is the characteristic capacitance of the power tube itself,

[0016] V DS is the working power supply voltage;

[0017] VGS is the driving voltage;

[0018] V gp is the saturation voltage of the power tube;

[0019] It is believed that the measurement system composed of an oscilloscope and a high-voltage probe can accurately collect the rise time t ≥ t r （ ns) pulse signal, thus proving the bandwidth of the high voltage probe B ≥350 / t r , thus realizing the traceability of the high voltage probe bandwidth.

[0020] According to the command input from the display control module, the STM32 single-chip microcomputer outputs instructions to the TTL signal driver module and the PWM modulation driver respectively, triggering the PWM high-voltage pre-stage driver module to conduct and work. After that, it is rectified by the rectification detection module and the rectification voltage multiplier module, and the output set high voltage enters the high-voltage switch module. The adjustable TTL signal output by the TTL signal driver module triggers the driver pre-stage of the high-voltage switch module, thereby controlling the opening and closing of the internal MOSFET, and outputting a controllable and programmable DC pulse signal on the glass glaze resistor-capacitor load. During operation, the PWM high-voltage pre-stage driver module, the high-voltage detection module, and the high-voltage switch module are subject to real-time detection by the feedback protection circuit. If a problem occurs, the system will automatically shut down and prompt an alarm.

[0021] Furthermore, the high-voltage pulse module uses optoelectronic isolation, operational amplifiers, Mosfet driver tubes, and multiple groups of parallel synchronous adjustable pulse output circuits. Each group of synchronous adjustable pulse output circuits consists of a pulse transformer, a resonance module, a protection module, a Mosfet power tube and an adjustable resistor connected in series in a loop; the TTL signal drive module outputs to the optoelectronic isolation, is amplified by the operational amplifier, and then drives the Mosfet driver tube connected to the primary side of the first group of pulse transformers, synchronously triggering the Mosfet power tube to turn on or off; the Mosfet power tube is composed of three SiC power MOSFET tubes of the same model and characteristics connected in series, which can achieve fast switching while enhancing the voltage resistance characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a circuit principle block diagram of the present invention;

[0023] Figure 2 This is a block diagram of the circuit principle of the high-voltage switch module of the present invention;

[0024] Figure 3 This is a schematic diagram of the high-voltage pulse module circuit of the present invention;

[0025] Figure 4 It is a circuit principle block diagram of the present invention;

[0026] Figure 5 It is a circuit principle block diagram of the present invention;

[0027] Figure 6 is a flow chart of the present invention;

[0028] Figure 7 This is a connection diagram of the high-voltage probe of the present invention;

[0029] Figure 8 This is a single pulse frequency demonstration diagram of the present invention;

[0030] Figure 9 This is a demonstration diagram of a single pulse waveform of the present invention when the voltage is 3kV and the rise time is 1.01ns;

[0031] Figure 10 This is a demonstration diagram of the rising edge and falling edge of a single pulse waveform of the present invention. DETAILED DESCRIPTION

[0032] like Figure 1 As shown, a nanosecond high-voltage pulse generator of the present invention includes a system power supply, an auxiliary power supply, a single-chip microcomputer, a display control module, a DC high-voltage drive circuit, a DC high-voltage switching circuit, a discharge protection circuit and a feedback protection circuit; the system power supply is connected to the auxiliary power supply, the single-chip microcomputer and the DC high-voltage drive circuit and supplies power; the mains 220V is filtered and rectified, enters the system power circuit, and is provided to the auxiliary power supply and the TTL signal driver module and the STM32 single-chip microcomputer circuit power supply respectively. The single-chip microcomputer is connected to the display control module, the DC high-voltage drive circuit, the DC high-voltage switching circuit and the feedback protection circuit respectively. In order to ensure that the digital visual environment is convenient for operation and control, an STM32 embedded single-chip microcomputer is adopted, and one-button control is realized by pre-programming to generate the required pulse signal source.

[0033] The output end of the auxiliary power supply is connected to the power supply end of the DC high-voltage switching circuit, the start-controlled end of the DC high-voltage switching circuit is connected to the output end of the DC high-voltage driving circuit, the DC high-voltage switching circuit is connected to the microcontroller through the feedback protection circuit, and the DC high-voltage switching circuit is also connected to the discharge protection circuit.

[0034] The DC high-voltage drive circuit includes a TTL signal driver module. The controlled terminal of the TTL signal driver module is connected to the microcontroller, and the output terminal of the TTL signal driver module is connected to the on-controlled terminal of the DC high-voltage switch circuit. A CPLD device generates a 5V TTL signal with a programmable pulse width. The TTL signal driver module is programmable and can output a TTL signal with a frequency of 0 to 5kHz and a specific step size, which is used to control the on and off of the high-voltage switch module.

[0035] The DC high-voltage switch circuit includes a PWM modulation drive module, a PWM high-voltage pre-stage drive module, a rectifier detection module, a rectifier voltage doubler module, a high-voltage switch module, and a DC high-voltage pulse output module, which are electrically connected in sequence. The PWM high-voltage pre-stage drive module, the rectifier detection module, the rectifier voltage doubler module, and the high-voltage switch module are respectively connected to a feedback protection circuit. The rectifier detection module is connected to a single-chip microcomputer via a detection module. The rectifier voltage doubler module is connected to a discharge protection circuit. The controlled end of the high-voltage switch module is connected to the output end of the TTL signal drive module. The modulation signal voltage of the present invention is continuously adjustable under programmable control. The PWM modulation drive module sends a PWM programmable modulation signal to the PWM high-voltage pre-stage drive module to generate a primary high voltage, which is then output to the rectifier detection module and the rectifier voltage doubler module, thereby obtaining a secondary high voltage, i.e., a DC high voltage of 200V to 3000kV. The secondary high voltage is then stored in a buffer capacitor and output to the DC high-voltage pulse output module as a DC high-voltage source.

[0036] like Figure 2 As shown, the high-voltage switch module consists of a high-voltage pulse module and a peripheral circuit. The peripheral circuit includes a coupling resistor, a buffer capacitor, a current limiting resistor, an RC absorption circuit and a feedback resistor. The output end of the TTL signal driving module is connected to the signal receiving port of the high-voltage pulse module through a coupling resistor. The output signal of the TTL signal driving module is used as a trigger signal for the high-voltage pulse module; the auxiliary power supply is connected to the power supply port of the high-voltage pulse module through a buffer capacitor; the alarm feedback port of the high-voltage pulse module is connected to the alarm end of the single-chip microcomputer, the high-voltage input end of the high-voltage pulse module is connected to the high-voltage source through a current limiting resistor, the high-voltage pulse module is also connected to the RC absorption circuit, and the high-voltage pulse module outputs a pulse DC signal through a feedback resistor.

[0037] like Figure 2 As shown, the high-voltage switch module consists of a high-voltage pulse module U1 and peripheral circuits. The high-voltage pulse module U1 (1) is connected to the auxiliary +5V power supply through a buffer capacitor. C 1 To provide working power for the internal circuit, the high voltage pulse module U1 (2) pin is connected to the external input TTL pulse signal as the trigger signal of the internal drive circuit. R 1 It is a signal coupling resistor that shapes the input TTL signal to reduce the ringing signal. The continuous trigger frequency of the TTL signal is less than 5kHz, and the maximum pulse group signal is no more than 1MHz. When the input TTL signal is incorrect, the high-voltage pulse module U1 (4) pin outputs a high-level signal as a protection signal, which is output to the STM32 microcontroller circuit for fault protection. The high-voltage pulse module U1 (3) pin and (6) pin are used as the low-voltage ground terminal and the high-voltage ground terminal respectively, using a star connection with a buffer capacitor. C 2The output terminal ground terminal is connected to the ground together to minimize signal interference. The high voltage pulse module U1 (5) pin is connected to the ground through a series current limiting resistor R 5 Connect to the DC high voltage power supply terminal, R 5 For the current limiting resistor, you can change the current limiting resistor R 5 The resistance value can be adjusted to suit the measurement or application requirements. R 2 、 C 3 The RC absorption circuit is formed in series, and the R 2 、 C 3 The size of the output DC pulse is improved as much as possible to eliminate the ringing interference. R 4 The feedback resistor is used. Since the high voltage pulse module U1 is set to a fixed on-time of 150ns and the load capacitance is not greater than 3nF, the maximum peak current is determined by the feedback resistor. R 4 The resistance value is determined by R 4 The resistance calculation formula ;

[0038] in, V o It is a DC high voltage. I p is the maximum peak current, R start is the static resistance value of the high voltage pulse module U1, R 3 As the load resistor, the high voltage DC signal passes through R 5 、R 3 、U 1 The required pulsed DC signal is formed and output to the external terminal block through the feedback resistor R4.

[0039] like Figure 3As shown, the high-voltage pulse module includes a photoelectric isolator, an operational amplifier, a Mosfet driver tube, and multiple groups of parallel synchronous adjustable pulse output circuits. Each group of synchronous adjustable pulse output circuits consists of a pulse transformer, a resonance module, a protection module, a Mosfet power tube and an adjustable resistor connected in series in a loop. The signal receiving end of the photoelectric isolator is connected to the output end of the TTL signal driver module, the output end of the photoelectric isolator is connected to the inverting input end of the operational amplifier, the non-inverting input end and output end of the operational amplifier are both connected to the gate of the Mosfet driver tube, and the drain of the Mosfet driver tube is connected to the primary side of the pulse transformer of the first group of synchronous adjustable pulse output circuits. The drain of the Mosfet driving tube is also connected to the power supply end of the auxiliary power supply. The secondary side of the pulse transformer of each group of synchronous adjustable pulse output circuits is connected to the gate of the Mosfet power tube through the resonance module and the protection module respectively. The drain of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the DC high-voltage power supply end, and the source of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the drain of the next group of Mosfet power tubes. Multiple Mosfet power tubes are connected in sequence, and the source of the Mosfet power tube of the last group of synchronous adjustable pulse output circuits is used as the output end to output an adjustable pulse signal. In order to generate high-voltage, high-current, fast-leading pulse signals, this circuit uses a high-voltage pulse module designed with imported modules from German HTS. Its core circuit uses a series connection of multiple MOSFET power tubes (MOSFET metal field-effect switch tubes). The specially designed drive circuit is coupled and synchronized through a pulse transformer to ensure the consistency and immediacy of the switching of each power tube. This allows the leading edge of the pulse signal to be stabilized at 1.4ns in a high-voltage (+200V~3000kV) and high-current (60A peak) working environment.

[0040] Specifically, such as Figure 1 and Figure 3 As shown in the figure, first, the STM32 microcontroller sends a control signal, which is output to the optoelectronic isolator via the TTL signal driver module. After being amplified by the operational amplifier, it drives the MOSFET driver tube connected to the primary side of the first set of pulse transformers, synchronously triggering the MOSFET power tube to turn on or off. The MOSFET power tube is composed of three SiC power MOSFET tubes of the same model and characteristics connected in series, achieving fast switching while enhancing the voltage resistance. The equivalent circuit of each MOSFET is shown in the figure. Figure 4 As shown, its switching time characteristics are as follows Figure 5 shown.

[0041] like Figure 4 and 5 As shown, t3 is the rising edge time when the switch is turned on, which can be calculated by the formula Calculation, formula is the impedance value of the resonant module R G And the Mosfet power tube's own resistance R g The sum of 25Ω, C gd is the characteristic capacitance of the power tube itself, , V DS is the working power supply voltage, set to 1000V, V GS The driving voltage is 10V, V gp is the saturation voltage of the power tube, and the characteristic value is , calculated by the formula: .

[0042] like Figure 8 As shown in the figure, a single pulse frequency display is demonstrated; Figure 9 As shown in FIG, it is demonstrated that when the voltage is 3kV, the rising edge time of a single pulse waveform reaches 1.01ns. Therefore, the present invention can not only achieve a rising edge time of 1.4ns, but also ideally achieve a rising edge time of 1.01ns or even shorter. Figure 10 As shown in the figure, the rising and falling edges of a single pulse waveform are displayed. As can be seen from the above figure, the present invention can generate high-voltage pulses with a rise time of less than 1.4ns and an amplitude of 3kV, solving the calibration problem of oscilloscopes and high-voltage probes in actual working conditions, effectively solving the value traceability problem of high-voltage probes in my country, and resolving the problem that has restricted the development of high-voltage pulse sources.

[0043] like Figure 6 As shown, the working principle of the nanosecond high-voltage pulse generator of the present invention is as follows:

[0044] Step 1. Turn on the system power supply and supply power to the STM32 microcontroller (2), TTL signal driver module (6) and 24V auxiliary power supply (8) after rectification and filtering. Reset the system and wait for operation instructions.

[0045] Step 2. According to the command input by the display control module (3), the STM32 microcontroller (2) outputs instructions to the TTL signal driver module (6) and the PWM modulation driver (4), respectively, triggering the PWM high-voltage pre-stage driver module (9) to turn on. After that, the rectifier detection module (10) and the rectifier voltage doubler module (11) perform rectification processing, and the output set high voltage enters the high-voltage switch module (12).

[0046] Step 3. The adjustable TTL signal output by the TTL signal driving module (6) triggers the driving front stage of the high-voltage switch module (12), thereby controlling the internal MOSFET to turn on and off, and outputting a controllable and programmable DC pulse signal on the glass glaze resistor and capacitor load.

[0047] Step 4. During operation, the PWM high-voltage pre-stage driver module (9), the high-voltage detection module (10), and the high-voltage switch module (12) will be detected in real time by the feedback protection circuit (7). If any problem occurs, the system will automatically shut down and an alarm will be prompted.

[0048] Step 5. After shutting down, the discharge protection circuit (14) automatically discharges the high voltage on the buffer capacitor, thereby playing a safety protection role.

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0050] like Figure 7 As shown, a method for tracing the rise time of a high-voltage probe based on a nanosecond-level high-voltage pulse generator includes the following steps:

[0051] A: Connect the output of the high-voltage pulse generator to the power supply of the high-voltage probe. Then, connect the attenuated high-voltage probe to an oscilloscope with a bandwidth twice that of the high-voltage probe to form a measurement system and acquire the complete waveform.

[0052] B: Use the oscilloscope's measurement function to measure the rise time of the high-voltage probe t , if the rise time t = t r × (1 ± 10%) ns, where t r is the rise time of the high voltage pulse generator, using the formula calculate;

[0053] In the formula, is the impedance value of the resonant module and the resistance R of the MOSFET power tube itself g sum;

[0054] C gd is the characteristic capacitance of the power tube itself,

[0055] V DS is the working power supply voltage;

[0056] V GS is the driving voltage;

[0057] V gp is the saturation voltage of the power tube;

[0058] It is believed that the measurement system composed of an oscilloscope and a high-voltage probe can accurately collect the rise timet ≥ t r （ ns) pulse signal, thus proving the bandwidth of the high voltage probe B ≥350 / t r , thus realizing the traceability of the high voltage probe bandwidth.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nanosecond high-voltage pulse generator, characterized in that: It includes a system power supply, an auxiliary power supply, a single-chip microcomputer, a display control module, a DC high-voltage drive circuit, a DC high-voltage switch circuit, a discharge protection circuit and a feedback protection circuit; the system power supply is connected to the auxiliary power supply, the single-chip microcomputer and the DC high-voltage drive circuit and supplies power, and the single-chip microcomputer is respectively connected to the display control module, the DC high-voltage drive circuit, the DC high-voltage switch circuit and the feedback protection circuit; the output end of the auxiliary power supply is connected to the power supply end of the DC high-voltage switch circuit, the start-controlled end of the DC high-voltage switch circuit is connected to the output end of the DC high-voltage drive circuit, the DC high-voltage switch circuit is connected to the single-chip microcomputer through the feedback protection circuit, and the DC high-voltage switch circuit is also connected to the discharge protection circuit; The DC high voltage drive circuit includes a TTL signal drive module; The DC high-voltage switch circuit includes a high-voltage switch module; the high-voltage switch module includes a high-voltage pulse module; The high-voltage pulse module includes a photoelectric isolator, an operational amplifier, a MOSFET driver tube, and multiple parallel synchronous adjustable pulse output circuits. Each synchronous adjustable pulse output circuit includes a circuit consisting of a pulse transformer, a resonance module, a protection module, a MOSFET power tube, and an adjustable resistor connected in series. The signal receiving end of the photoelectric isolator is connected to the output end of the TTL signal driver module, the output end of the photoelectric isolator is connected to the inverting input end of the operational amplifier, the in-phase input end and output end of the operational amplifier are both connected to the gate of the MOSFET driver tube, and the drain of the MOSFET driver tube is connected to the primary side of the pulse transformer of the first synchronous adjustable pulse output circuit. The drain of the Mosfet driving tube is also connected to the power supply end of the auxiliary power supply. The secondary side of the pulse transformer of each group of synchronous adjustable pulse output circuits is connected to the gate of the Mosfet power tube through the resonance module and the protection module respectively. The drain of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the DC high-voltage power supply end, and the source of the Mosfet power tube of the first group of synchronous adjustable pulse output circuits is connected to the drain of the next group of Mosfet power tubes. Multiple Mosfet power tubes are connected in sequence, and the source of the Mosfet power tube of the last group of synchronous adjustable pulse output circuits is used as the output end to output an adjustable pulse signal.

2. The nanosecond high-voltage pulse generator according to claim 1, characterized in that: The DC high-voltage drive circuit includes a TTL signal drive module, a controlled end of the TTL signal drive module is connected to the single-chip microcomputer, and an output end of the TTL signal drive module is connected to the open controlled end of the DC high-voltage switch circuit.

3. The nanosecond high-voltage pulse generator according to claim 2, characterized in that: The DC high-voltage switching circuit includes a PWM modulation drive module, a PWM high-voltage pre-stage drive module, a rectifier detection module, a rectifier voltage doubler module, a high-voltage switch module and a DC high-voltage pulse output module, which are electrically connected in sequence. The PWM high-voltage pre-stage drive module, the rectifier detection module, the rectifier voltage doubler module and the high-voltage switch module are respectively connected to the feedback protection circuit, the rectifier detection module is connected to the single-chip microcomputer through the differential detection module, the rectifier voltage doubler module is connected to the discharge protection circuit, and the controlled end of the high-voltage switch module is connected to the output end of the TTL signal drive module.

4. The nanosecond high-voltage pulse generator according to claim 3, characterized in that: The high-voltage switch module consists of a high-voltage pulse module and a peripheral circuit. The peripheral circuit includes a coupling resistor, a buffer capacitor, a current limiting resistor, an RC absorption circuit and a feedback resistor. The output end of the TTL signal driving module is connected to the signal receiving port of the high-voltage pulse module through a coupling resistor, and the output signal of the TTL signal driving module is used as a trigger signal for the high-voltage pulse module; the auxiliary power supply is connected to the power supply port of the high-voltage pulse module through a buffer capacitor; the alarm feedback port of the high-voltage pulse module is connected to the alarm end of the single-chip microcomputer, the high-voltage input end of the high-voltage pulse module is connected to the high-voltage source through a current limiting resistor, the high-voltage pulse module is also connected to the RC absorption circuit, and the high-voltage pulse module outputs a pulse DC signal through the feedback resistor.

5. A method for tracing the rise time of a high-voltage probe of a nanosecond-level high-voltage pulse generator according to any one of claims 1 to 4, characterized in that: The following steps are involved: A: Connect the output of the high-voltage pulse generator to the power supply of the high-voltage probe. Then, connect the attenuated high-voltage probe to an oscilloscope with a bandwidth twice that of the high-voltage probe to form a measurement system and acquire the complete waveform. B: Use the oscilloscope's measurement function to measure the rise time of the high-voltage probe t , if the rise time t = t r × (1 ± 10%) ns, where t r is the rise time of the high voltage pulse generator, using the formula calculate; In the formula, is the impedance value of the resonant module and the resistance R of the MOSFET power tube itself g sum; C gd is the characteristic capacitance of the power tube itself, V DS is the working power supply voltage; V GS is the driving voltage; V gp is the saturation voltage of the power tube; It is believed that the measurement system composed of an oscilloscope and a high-voltage probe can accurately collect the rise time t ≥ t r （ ns) pulse signal, thus proving the bandwidth of the high voltage probe B ≥350 / t r , thus realizing the traceability of the high voltage probe bandwidth.

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