Pulse stable output control method and system for ns-level high repetition frequency fast pulse power supply

Abstract

The invention discloses a pulse stable output control method and system for an ns-level high repetition frequency fast pulse power supply, and relates to the technical field of automatic control, the system is composed of a plurality of functional modules, and the system comprises a self-adaptive absorption module, a control module and an output control module, and the self-adaptive absorption module obtains power supply parameters through real-time sampling, and the power supply parameters comprise load impedance and switch tube parasitic parameters; dynamically optimizing R and C parameters of the RCD absorption circuit and the active clamping circuit based on power supply parameters; the feed-forward prediction module is used for extracting derivative state information according to the power supply parameters, acquiring load current feed-forward and resonant circuit states based on the derivative state information, modeling based on the load current feed-forward and resonant circuit states, and predicting the drain-source voltage valley bottom moment of the switch tube; and the multi-section variable impedance transmission module adopts a three-section variable impedance structure, performs broadband impedance matching based on R and C parameters of the optimized RCD absorption circuit and the active clamping circuit, inhibits pulse leading edge reflection distortion, and outputs undistorted pulse signals.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic control, in particular to a pulse stable output control method and system of an ns-level high-repetition-rate fast pulse power supply. BACKGROUND

[0002] The high-repetition-rate fast pulse power supply is a kind of special power supply with high repetition frequency and fast pulse dynamic characteristics, which can continuously output narrow pulse width, steep front and back edges, and high power density of electric energy. The essence is to convert conventional electric energy into short-time, high-intensity and high-frequency pulse electric energy through precise circuit control, break through the energy transmission limitation of traditional continuous wave power supply, and based on the characteristics of short pulse, high frequency and low heat damage, the power supply is widely used in frontier fields such as scientific research exploration and high-end manufacturing. It is the core power source of key equipment and the key basic equipment for technological breakthrough in frontier science and technology fields such as chip manufacturing and quantum physics. Its performance directly determines the accuracy, efficiency and reliability of the downstream system.

[0003] The traditional ns-level high-repetition-rate fast pulse power supply technology still has multi-dimensional bottlenecks, which is difficult to meet the needs of high-end scenes for stability, efficiency and precision. The R and C parameters of the RCD absorption circuit and the active clamp circuit are mostly fixed values, which cannot dynamically respond to the real-time changes of the load impedance, such as the time-varying impedance of the plasma load and the parasitic parameters of the switching tube, such as the real-time changes of the parasitic capacitance and inductance of the drain and source. This leads to unstable voltage spike suppression effect, such as high peak voltage or energy loss of the device when the load suddenly changes. The static parameter adaptation is single working condition. At the same time, in the high-power scene, the voltage and current equalization of IGBT and other switching devices is a prominent problem, which is easy to cause damage due to uneven stress of the device. The traditional method is directly based on the original power supply parameter calculation, and the influence of the impedance dynamic change rate and the parasitic parameter coupling characteristics is not considered, which leads to large prediction deviation of the load current peak value and the rising slope. Most of them use fixed impedance matching scheme, which cannot adapt to the pulse characteristics of different frequency components in a wide frequency band, and is easy to produce front reflection distortion at the transmission interface. SUMMARY

[0004] In order to achieve the above purpose, the present application is realized by the following technical scheme: A pulse stable output control system of an ns-level high-repetition-rate fast pulse power supply, comprising: An adaptive absorption module acquires power supply parameters through real-time sampling, including load impedance and switching tube parasitic parameters, and dynamically optimizes the R and C parameters of the RCD absorption circuit and the active clamp circuit based on the power supply parameters; A feedforward prediction module extracts derived state information according to the power supply parameters, obtains load current feedforward and resonant loop state based on the derived state information, and models based on the load current feedforward and resonant loop state to predict the trough time of the switching tube drain-source voltage; The multi-section variable impedance transmission module adopts a three-section variable impedance structure, performs wide-band impedance matching based on optimization of R, C parameters of an RCD absorption circuit and an active clamp circuit, and outputs a distortionless pulse signal. The cooperative protection module performs dynamic threshold adjustment and high-speed circuit control based on the distortionless pulse signal and in combination with a predicted moment of a bottom of a drain-source voltage of the switch tube.

[0005] Further, the load impedance is converted into a digital sequence by collecting voltage and current signals at both ends of the load. The parasitic parameters of the switch tube include a drain-source parasitic capacitance, a gate-source and gate-drain parasitic capacitance, and a parasitic inductance.

[0006] Further, the process of dynamically optimizing the R, C parameters of the RCD absorption circuit and the active clamp circuit is as follows: Based on the power supply parameters, a simulation model is used to simulate the working behavior of the RCD absorption circuit and the active clamp circuit under different R, C parameters, an adaptive intelligent optimization algorithm is used to search for the optimal R, C combination in a preset parameter range, the actual circuit parameters are dynamically adjusted, and the actual working state of the circuit is continuously monitored, real-time data is fed back to the simulation model, and the R, C parameters are iteratively optimized.

[0007] Further, the process of extracting derivative state information from the power supply parameters is as follows: The power supply parameters are preprocessed to eliminate sampling noise and time sequence deviation, effective signal components matching the working frequency band of the power supply are reserved through band-pass filtering, time axis is completely aligned through time sequence synchronization calibration, and derivative state information is extracted.

[0008] Further, the process of obtaining load current feedforward and resonant loop state is as follows: The adaptive load current feedforward prediction model is constructed with the derivative state information as input, pulse driving characteristics are output, the dynamic change rate of the load impedance and the amplitude correlation law of the current are analyzed based on the pulse driving characteristics, the peak value, rising edge and falling edge slope, and duration of the current are predicted, the load current feedforward is output by correcting the influence of the parasitic effect on current transmission by using the coupling characteristics of the parasitic parameters of the switch tube. Based on the derivative state information, the resonant loop state jointly acted on by the parasitic parameters of the switch tube and the load impedance is analyzed, the resonant loop state frequency is calculated by using the parasitic parameters of the switch tube, the resonant energy loss of the resonant loop state frequency and the power supply working frequency is judged, the current phase position is determined through the time sequence correlation characteristics of the load impedance and the parasitic parameters of the switch tube, and the resonant loop state is judged based on the corresponding relationship between the current phase position and the resonant energy loss.

[0009] Further, the process of modeling based on the load current feedforward and the resonant loop state is as follows: The peak value, rising edge or falling edge slope, and duration critical features of the load current are fed forward; the real-time resonant frequency and current phase position parameters of the resonant circuit state are extracted; the time axis is aligned based on the timing synchronization mechanism to eliminate timing deviation; A cooperative adaptive prediction model of load current feedforward and resonant circuit state is constructed, including timing correlation modeling and energy change modeling; the phase correlation law of load current feedforward features and resonant circuit is analyzed, the timing coupling coefficient is quantified, the mapping relationship between current features and phase change is established, and the timing correlation modeling is constructed; The relationship between the resonant circuit energy exchange process and the drain-source voltage rising and falling trend of the switch tube is analyzed, the influence of the load current feedforward on the energy loss is combined, and the dynamic modeling is performed based on the resonant energy state and the drain-source voltage rising and falling trend of the switch tube to construct the energy change model.

[0010] Further, the process of predicting the valley bottom time of the drain-source voltage of the switch tube is as follows: The timing correlation model and the energy change model are quickly calculated using the parallel computing capability of the FPGA, and the dynamic change curve of the drain-source voltage of the switch tube is output, and the calculation delay is controlled within a single pulse period; based on the voltage change curve, the time when the voltage falling stage rate changes from fast to slow, approaches to 0 and is about to turn to rising is identified as the valley bottom time of the drain-source voltage; combined with the real-time phase position verification of the resonant circuit, if there is deviation, the valley bottom time is adjusted through the phase correction coefficient to ensure that the valley bottom time is completely matched with the resonant circuit energy state.

[0011] Further, the process of outputting a distortionless pulse signal is as follows: Based on the wideband impedance matching of the three-section variable impedance structure, the input matching section accurately matches the equivalent output impedance after the optimized R, C parameters of the previous stage, the intermediate transition section realizes impedance smooth transition according to the uniform gradient, and the output matching section is real-time matched with the load impedance, and the three sections form an impedance transmission link without mutation, and the lengths of the three transmission lines are all according to the characteristic wavelength of the corresponding working frequency band; The transmission medium is selected, the high-frequency compensation structure is added in the intermediate transition section, and the pulse front shape and reflection coefficient distortion index are real-time collected; the monitoring data are fed back to the FPGA control unit, the impedance values and transmission line compensation parameters of the three-section structure are dynamically adjusted combined with the optimized R, C parameters of the previous stage and the load impedance change trend; based on the prediction timing of the valley bottom time of the drain-source voltage of the switch tube, the output pulse timing is calibrated through the delay line fine tuning technology to ensure that the front trigger time and the valley bottom time are accurately synchronized; after completing a pulse period, the measured waveform of the output pulse is compared with the preset distortionless standard waveform, and the distortion degree is quantified; if the distortion index exceeds the allowed range, the impedance matching algorithm and the transmission line compensation parameters are updated through the DSP to iteratively optimize the dynamic response characteristics of the three-section variable impedance structure, and finally a distortionless pulse signal is output.

[0012] Further, the dynamic threshold adjustment and high-speed circuit control process is: Based on the distortionless pulse reference characteristics and the valley bottom time sequence, the overvoltage threshold and the overcurrent threshold are dynamically adjusted, the overvoltage threshold is adjusted based on the pulse amplitude and combined with the valley voltage characteristics, the overcurrent threshold is dynamically set according to the pulse front slope and the load current feedforward, and the valley bottom time is relaxed and deviated, and then tightened; the overvoltage threshold and the overcurrent threshold are both linked to the optimized R, C parameters for adaptive matching; In normal operation, within the distortionless pulse timing window, the main switch tube is turned on at the valley bottom time, and the active clamp circuit switch tube is controlled synchronously; when the parameters exceed the threshold, the FPGA outputs a shutdown signal and strengthens the RCD absorption; when the valley bottom time deviates, the turn-on timing is adjusted and the threshold is temporarily tightened. Real-time monitoring of control effect, deviation analysis, adjustment of threshold or timing calibration parameters; every preset pulse period, solidification of optimized parameters and retention of real-time update channel.

[0013] A pulse stable output control method of a ns-level high-repetition-rate fast pulse power supply, comprising the following steps: Step one, obtain the power supply parameters including load impedance and switch tube parasitic parameters by real-time sampling, and dynamically optimize the R, C parameters of the RCD absorption circuit and the active clamp circuit based on the power supply parameters; Step two, derive state information based on the power supply parameters, obtain load current feedforward and resonant circuit state based on the derived state information, model based on the load current feedforward and resonant circuit state, and predict the valley bottom time of the switch tube drain-source voltage; Step three, use a three-section variable impedance structure, perform wideband impedance matching based on the optimized R, C parameters of the RCD absorption circuit and the active clamp circuit, suppress pulse front reflection distortion, and output a distortionless pulse signal; Step four, based on the distortionless pulse signal, combined with the predicted valley bottom time of the switch tube drain-source voltage, dynamically adjust the threshold and control the high-speed circuit.

[0014] The pulse stable output control method of the ns-level high-repetition-rate fast pulse power supply provided by the application has the following beneficial effects: (1) The application can dynamically match the changes of load impedance and switch tube parasitic parameters by optimizing the R, C parameters of the RCD absorption circuit and the active clamp circuit in real time, effectively suppresses voltage spikes, ensures that the switch tube voltage stress is within the safety threshold, reduces the energy loss of the absorption circuit, improves the overall efficiency of the power supply, greatly enhances the adaptive ability of the circuit to dynamic load, and ensures the long-term stable operation of the switch tube.

[0015] (2) The load current feedforward and the resonant loop state model constructed by the derived state information can accurately predict the moment when the switch tube drain-source voltage bottom, realize the switch tube zero voltage turn-on, and reduce the switching loss; at the same time, the accurate control of the load current and the resonant loop state also significantly improves the output stability of the power supply under high frequency conditions.

[0016] (3) The three-section variable impedance structure and the dynamic optimization mechanism can realize wideband impedance matching, effectively suppress the pulse front reflection distortion, output distortionless pulse signal, and the front is steep without oscillation, the amplitude is stable without fluctuation; combined with the dynamic threshold adjustment and high-speed circuit control at the bottom moment of the distortionless pulse, the problems of false protection or delayed protection are avoided, and the overall reliability and anti-interference ability of the power supply are greatly enhanced, which meets the harsh needs of high-end scientific research and industrial scenes. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a system flowchart of the present application; Figure 2 is a whole method schematic diagram of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0019] Embodiment 1: Please refer to Figure 1 Embodiment 1 of the present application provides a pulse stable output control system of a ns-level high frequency fast pulse power supply, which comprises: An adaptive absorption module acquires power supply parameters including load impedance and switch tube parasitic parameters through real-time sampling, and dynamically optimizes R, C parameters of RCD absorption circuit and active clamping circuit based on the power supply parameters; A high-sensitivity sensor respectively collects load voltage, load current and multi-terminal signals of the switch tube, constructs a picosecond-level synchronous clock, provides synchronous trigger signals for all sampling channels, ensures that the sampling time deviation of voltage, current and switch tube signals is extremely small, and performs time alignment of multiple parameters.

[0020] Real-time acquisition and calculation of load impedance: The voltage and current signals at both ends of the load are acquired synchronously, the analog signals are converted into digital sequences, the digital sequences are bandpass filtered to remove electromagnetic interference outside the power supply frequency band, the amplitude ratio and phase difference of the filtered voltage and current signals are analyzed, and the load impedance is calculated pulse by pulse. Since the power supply has a high repetition rate in the nanosecond range, the load impedance needs to be updated once in each pulse cycle to ensure real-time performance.

[0021] Real-time extraction of parasitic parameters of switching transistors: Parasitic parameters of a switching transistor include drain-source parasitic capacitance, gate-source and gate-drain parasitic capacitance, and parasitic inductance. Taking drain-source parasitic capacitance as an example, during the turn-off phase of the transistor, the rate of change of the drain-source voltage is observed, and the magnitude of the drain-source parasitic capacitance is calculated by combining the turn-off status of the drain current. The gate-source and gate-drain parasitic capacitance is extracted through the coupling characteristics between the gate drive signal and the drain voltage. For parasitic inductance, during the turn-on phase of the transistor, the rising slope of the drain current and the corresponding transient voltage drop are observed, and then the parasitic inductance is calculated. Since these parameters are affected by factors such as temperature, they need to be corrected through online calibration to ensure their accuracy.

[0022] The process of dynamically optimizing the R and C parameters of the RCD snubber circuit and the active clamping circuit is as follows: By acquiring the load impedance and parasitic parameters of the switching transistor in the sampling stage, the load characteristics of the current power supply and the inherent electrical characteristics of the switching transistor are reflected. Based on the acquired power supply parameters, a dynamic simulation model of the RCD snubber circuit and the active clamping circuit is built to accurately simulate the circuit's operating behavior under different R and C parameters, including the suppression effect of the RCD snubber circuit on the voltage spike when the switching transistor is turned off and its energy absorption efficiency; the optimization of the switching transistor's turn-on or turn-off timing by the active clamping circuit and the stability of the clamping voltage; and the impact of changes in load impedance and parasitic parameters of the switching transistor on circuit characteristics, such as changes in spike voltage amplitude and circuit losses. Adaptive intelligent optimization algorithms, such as adaptive genetic algorithms and particle swarm optimization algorithms, are employed to determine the optimal combination within the preset R and C parameter range, taking into account the physical characteristics of circuit components and the power supply operating frequency band. The search maximizes voltage spike suppression capability, ensuring that the voltage stress of the switching transistor is within a safe threshold; minimizes the energy loss of the absorption circuit, improving the overall efficiency of the power supply; and adapts to the current load impedance and parasitic parameters of the switching transistor to optimize the dynamic characteristics of the circuit, such as response speed and stability.

[0023] According to the optimized R, C parameters, the parameter update is completed by driving the programmable element through the high-speed digital control circuit, the digital potentiometer is adopted, and the resistance value is changed in real time through the digital signal; the programmable capacitor array is adopted, and the capacitance dynamic adjustment is realized by switching different combinations of capacitors; the whole adjustment process needs to be completed within ns level time to match the high repetition frequency characteristics of the power supply; after the parameter adjustment, the module continuously monitors the actual working state of the circuit, such as the drain-source voltage peak amplitude of the switch tube, the power consumption of the absorption circuit, the integrity of the pulse waveform and the like; the R, C parameters of the RCD absorption circuit and the active clamping circuit can match the dynamic characteristics of the load and the switch tube in real time, which not only effectively suppresses the voltage peak and ensures the safety of the switch tube, but also reduces the energy loss, and finally realizes the stable output of the ns level high repetition frequency fast pulse power supply.

[0024] The feedforward prediction module extracts derived state information according to the power supply parameters, obtains load current feedforward and resonant loop state based on the derived state information, and models based on the load current feedforward and the resonant loop state to predict the switch tube drain-source voltage valley time; The power supply parameters are derived to extract state information: The real-time sampled power supply parameters, including load impedance and switch tube parasitic parameters, are preprocessed with high precision to eliminate sampling noise and time sequence deviation; through band-pass filtering, the effective signal components matched with the power supply working frequency band are reserved, and combined with picosecond-level time sequence synchronous calibration, the time axis of the two types of parameters is completely aligned to extract key derived state information, including the dynamic change rate of the load impedance, reflecting the real-time fluctuation trend of the load characteristics; the coupling characteristics of the switch tube parasitic parameters, the equivalent combination effect of the parasitic inductance and the parasitic capacitance; the time sequence correlation characteristics of the impedance and the parasitic parameters, and the collaborative change law of the two with the pulse period.

[0025] Based on the derived state information, a load current feedforward model is constructed: Taking the extracted derived state information as the core input, an adaptive load current feedforward prediction model is constructed; combined with the inherent driving characteristics of the power supply output pulse, such as the time sequence parameters of the gate drive signal, the peak value, the rising or falling slope and the duration of the load current are predicted by analyzing the correlation between the load impedance dynamic change rate and the current amplitude; at the same time, the influence of parasitic effects on current transmission is corrected by using the coupling characteristics of the switch tube parasitic parameters, such as the current delay caused by parasitic inductance and the current fluctuation caused by parasitic capacitance; the model adopts real-time features and historical trend double-dimensional prediction logic, and the feedforward signal is quickly output through FPGA parallel calculation, so as to ensure that the time sequence deviation between the feedforward current and the actual load current is controlled within nanoseconds, and the advance prediction of the load current change is realized.

[0026] Based on the derived state information, the resonant loop state is analyzed: The core constituting parameters of the resonance loop, including equivalent inductance and equivalent capacitance, are determined by the parasitic parameters of the switch tube, including parasitic inductance and parasitic capacitance, and the load impedance. The real-time state of the resonance loop can be accurately analyzed through the derived state information. The actual resonance frequency of the loop is calculated by using the equivalent resonance characteristics of the parasitic parameters of the switch tube, including the combined resonance frequency of the parasitic inductance and capacitance, and the damping effect of the load impedance on the resonance. It is judged whether the resonance frequency matches the power supply operating frequency. Through the time sequence correlation characteristics of impedance and parasitic parameters, the phase synchronization state of the resonance loop is analyzed to determine the phase position in the resonance period at the current moment, such as the resonance rising section, peak section and decay section. Based on the corresponding relationship between the dynamic change rate of the load impedance and the resonance energy loss, the energy exchange efficiency of the loop is evaluated to determine whether there is a risk of rapid resonance decay or resonance out of control. The derived state information is processed quickly by DSP to ensure that the analysis results of the resonance loop state are updated synchronously with the power supply pulse period, and the dynamic changes of the loop are reflected in real time.

[0027] Feature extraction and time sequence calibration of input load current feedforward and resonance loop state: The obtained load current feedforward signal and resonance loop state information are preprocessed to ensure the effectiveness of the modeling input. For the load current feedforward signal, key features such as peak value, rising or falling edge slope, duration and dynamic fluctuation amplitude are extracted to reflect the demand changes of the load to the current. For the resonance loop state, core characteristic parameters are extracted, including real-time resonance frequency, current phase position, energy exchange efficiency and resonance decay rate, to clearly determine the dynamic working state of the loop. At the same time, based on the picosecond-level time sequence synchronization mechanism, the time axes of the two types of parameters are completely aligned to eliminate time sequence deviation and avoid modeling errors caused by different time synchronization.

[0028] Building a predictive model of load current feedforward and resonance loop state coordination and self-adaptation: Taking the preprocessed feature parameters as input, a self-adaptive predictive model of load current feedforward and resonance loop state coordination is constructed, and time sequence correlation modeling and energy change modeling are performed respectively. Time sequence correlation modeling: analyze the correlation law between load current feedforward features and resonance loop phase. The change of load current will affect the phase evolution of resonance loop through impedance coupling, for example, the current peak rising will accelerate the resonance phase advancement, and the current decay will slow down the phase change. By quantifying the time sequence coupling coefficient of the two, the mapping relationship between current features and phase change is established to determine the phase evolution speed of the resonance loop under different current states.

[0029] Energy change modeling: the energy exchange process of the resonant circuit directly determines the rising and falling trend of the drain-source voltage of the switch tube. When the circuit is in the energy charging stage, the drain-source voltage shows an upward trend; when it is in the energy releasing stage, the drain-source voltage shows a downward trend; the valley moment corresponds to the critical state of the lowest energy release of the resonant circuit, that is, about to enter the next round of energy charging; combined with the energy exchange efficiency and decay rate of the resonant circuit, and the influence of load current feedforward on energy loss, such as the increase of load current leading to the increase of circuit energy loss, the valley voltage rises slightly, a dynamic model of resonant energy state and drain-source voltage change is established, and the rate of voltage change with energy is quantified.

[0030] The model adopts an adaptive updating mechanism. After completing each pulse period, the timing coupling coefficient and energy mapping parameters are adjusted according to the measured drain-source voltage change data, so as to ensure that the model always adapts to the dynamic changes of the load and the circuit state.

[0031] Predicting the valley moment of the drain-source voltage of the switch tube: Through the FPGA+DSP heterogeneous computing architecture, the collaborative prediction model is solved at high speed to predict the valley moment of the drain-source voltage of the switch tube. The parallel computing capability of FPGA is used to quickly operate the timing correlation model and the energy change model, and the dynamic change curve of the drain-source voltage of the switch tube is output. The operation delay is controlled within a single pulse period. Combined with the real-time phase position of the resonant circuit, if the valley moment corresponds to the zero point of the resonant circuit phase, that is, the critical phase of energy exchange, it is confirmed that this moment is the effective valley. If there is a deviation, the phase correction coefficient is fine-tuned to ensure that the locked valley moment completely matches the energy state of the resonant circuit. After each pulse period ends, the measured valley moment of the drain-source voltage of the switch tube is collected and compared with the model predicted moment to calculate the deviation. If the deviation exceeds the preset threshold, the reason for the deviation is analyzed. If the inaccuracy of the load current feedforward feature extraction leads to it, the current feature extraction algorithm is optimized. If it is caused by the drift of the resonant circuit state parameters, the energy mapping parameters in the model are adjusted, and the corrected parameters are updated to the prediction model in real time to realize the dynamic iteration of the model and ensure that the deviation between the predicted valley moment and the measured value is stably controlled within ≤2ns in long-term work.

[0032] Multi-section variable impedance transmission module, adopting a three-section variable impedance structure, based on the R, C parameters of the optimized RCD absorption circuit and active clamping circuit for wideband impedance matching, suppressing pulse front reflection distortion, and outputting distortionless pulse signals; Adopting a three-section variable impedance structure: A three-section variable impedance transmission topology composed of an input matching section, an intermediate transition section, and an output matching section is built. The three-section structure is connected in series between a pre-stage circuit and a load to form a continuous impedance gradient path. The pre-stage circuit is an RCD absorption circuit and an active clamping circuit. Based on the optimized R and C parameters, the target of wideband impedance matching is determined. On the one hand, the effective working bandwidth of the output pulse of the pre-stage circuit after parameter optimization is covered, covering the frequency band of hundreds of MHz to GHz corresponding to the high repetition frequency of the power supply. On the other hand, the impedance gradient is used to eliminate the impedance discontinuity between different sections, suppress the reflection and distortion of the pulse front, and ensure efficient transmission of pulse energy to the load while maintaining waveform integrity. The voltage spike and energy loss of the pre-stage circuit are greatly reduced through the optimized R and C parameters, so that the output impedance of the pre-stage circuit presents stable dynamic characteristics, providing a low-distortion and high-stability reference for the impedance matching of the three-section structure, and avoiding the problem of insufficient matching accuracy caused by pulse distortion in traditional fixed impedance matching.

[0033] Wideband impedance matching: With the optimized R and C parameters and the real-time sampled load impedance as inputs, the target impedance value of the three-section structure is quickly calculated by the DSP to ensure that the gradient logic of each section is adapted to the characteristics of the pre-stage circuit and the load. The input matching section determines the equivalent output impedance of the pre-stage circuit through the optimized R and C parameters. This impedance is dynamically adjusted by the R and C parameters, and the impedance value of the input matching section needs to be matched with the equivalent output impedance in real time. When the R and C parameters are adjusted to high absorption capacity to suppress voltage spikes, the output impedance of the pre-stage will change accordingly. The input matching section dynamically adjusts its impedance to avoid pulse reflection between the pre-stage and the transmission module due to impedance mismatch. The intermediate transition section uses linear gradient and high-frequency compensation methods to distribute the gradient impedance according to the impedance difference between the input matching section and the output matching section with a uniform gradient. At the same time, the gradient curve is fine-tuned in combination with the pulse high-frequency component proportion corresponding to the optimized R and C parameters to ensure that pulses of different frequency components in the wideband can be smoothly transitioned, avoiding waveform distortion caused by high-frequency component reflection.

[0034] The output matching section directly matches the real-time sampled load impedance while referring to the stabilizing effect of the pulse amplitude by the optimized R and C parameters. When the pulse amplitude fluctuation amplitude is ≤5% due to the optimization of R and C parameters, the output matching section does not need to frequently and significantly adjust the impedance. It only needs to make small corrections according to the dynamic change rate of the load impedance to maintain the matching accuracy and ensure efficient injection of pulse energy into the load.

[0035] According to the power supply operating frequency band and pulse characteristics, the input matching section and the output matching section select microstrip lines or coaxial lines with excellent high-frequency characteristics to reduce transmission loss, and the middle transition section adopts a programmable gradual transmission line structure; the lengths of the three sections of transmission lines are designed according to 1 / 4 wavelength or 1 / 8 wavelength of the corresponding frequency band to ensure the consistency of impedance matching of each frequency component in the wide frequency band; each section is integrated with programmable impedance elements, such as digital control type microstrip line impedance adjuster, high-frequency programmable capacitor and inductor array, and the FPGA controls the element parameters in real time according to the target impedance value calculated by the DSP through high-speed digital signals to realize nanosecond-level adjustment of the impedance value, which is synchronized with the update frequency of the optimized R and C parameters, and is updated once per pulse cycle to ensure that the impedance matching always adapts to the dynamic characteristics of the previous stage circuit.

[0036] In view of the impedance characteristic differences of different frequency components in the wide frequency band, a frequency adaptive gradual algorithm is introduced in the middle transition section to dynamically adjust the gradient density of the gradual impedance according to the pulse high-frequency component intensity corresponding to the optimized R and C parameters, so that when the high-frequency component ratio is high, the gradient density is increased to improve the high-frequency matching precision, and when the low-frequency component ratio is high, the gradient density is appropriately reduced to balance the transmission efficiency, and low reflection and low loss transmission are realized in the whole frequency band.

[0037] After completing the impedance matching of each pulse cycle, the reflection coefficient, waveform distortion rate and energy transmission efficiency of the output pulse of the transmission module are monitored in real time: if the reflection coefficient is detected to be out of standard, it indicates that there is impedance mismatching, or the waveform appears front edge distortion, then the impedance values of the three sections are adjusted in reverse according to the current configuration of the optimized R and C parameters and the load impedance change trend; for example, if the output impedance of the previous stage is increased due to the adjustment of R and C parameters, the impedance value of the input matching section can be increased synchronously; if the output end is reflected due to the sudden change of the load impedance, the gradual gradient of the output matching section and the middle transition section can be mainly corrected.

[0038] Output undistorted pulse signal: Based on the wide frequency band impedance matching result of the three-section variable impedance structure, the causes of pulse reflection are eliminated through the continuously gradual impedance path; the input matching section accurately matches the equivalent output impedance after the optimization of R and C parameters of the previous stage, the middle transition section realizes impedance smooth transition according to the uniform gradient, and the output matching section real-time matches the load impedance, so that the three-section structure forms an impedance transmission link without mutation, avoiding the reflection wave at the interface between different sections due to the impedance mutation, and according to the high-frequency characteristics of the ns-level pulse, the lengths of the three sections of transmission lines are designed according to the characteristic wavelengths of the corresponding operating frequency bands to ensure that the pulses of each frequency component in the wide frequency band can realize impedance matching, thereby fundamentally suppressing the front edge reflection.

[0039] By selecting low-loss, high-frequency characteristic stable transmission medium, such as polytetrafluoroethylene microstrip line, silver-coated coaxial line, reducing energy loss and dispersion phenomenon in the process of pulse transmission, avoiding the front edge distortion caused by uneven medium characteristics; The three-section structure adopts shielding design, the outer layer is wrapped with a ground shielding layer, which isolates the influence of external electromagnetic interference on the pulse front edge, and at the same time suppresses the radiation interference of the transmission line itself; Optimize the wiring process of the transmission line, shorten the lead length, reduce the bending angle, and reduce the influence of parasitic inductance and parasitic capacitance on the pulse front edge; Add high-frequency compensation structure in the middle transition section to offset the front edge delay and distortion caused by transmission line parasitic parameters, and ensure the steepness and integrity of the pulse front edge.

[0040] Integrate a high-speed monitoring unit at the output end of the three-section variable impedance transmission module, real-time collect the front edge shape, reflection coefficient, amplitude fluctuation and other indicators of the pulse signal, monitor whether the front edge has overshoot, oscillation, delay and other distortion phenomena, and whether the reflection coefficient exceeds the preset threshold. The monitoring data is fed back to the FPGA control unit through the high-speed bus, combined with the optimized R, C parameters of the previous stage and the load impedance change trend, dynamically adjust the impedance value and transmission line compensation parameters of the three-section structure. If oscillation distortion caused by front edge reflection is detected, fine-tune the impedance gradient of the middle transition section, increase the gradient density, and enhance the matching accuracy of high-frequency components; If front edge delay distortion occurs, optimize the impedance adaptation degree of the input matching section and the previous circuit, reduce energy transmission loss, and improve the front edge rise rate; If amplitude fluctuation distortion is caused by sudden change of load impedance, quickly adjust the output matching section impedance, and simultaneously correct the gradient curve of the middle transition section to maintain the stability of the pulse amplitude.

[0041] Using the high stability of the pulse after the R, C parameter optimization, adding a front edge shaping unit at the output end of the transmission module, compressing the pulse front edge rise time through high-speed switching devices and RC buffer networks, and suppressing overshoot, making the front edge steeper and more regular; After completing one pulse period, compare the measured waveform of the output pulse with the preset distortionless standard waveform, and quantify the distortion degree, such as front edge distortion rate, amplitude fluctuation amplitude, and reflected energy proportion; If the distortion index exceeds the allowed range, update the impedance matching algorithm and transmission line compensation parameters through DSP, and iteratively optimize the dynamic response characteristics of the three-section variable impedance structure.

[0042] Collaborative protection module, based on distortionless pulse signal, combined with the predicted switch tube drain-source voltage trough time, dynamic threshold adjustment and high-speed circuit control; With the reference characteristics of the undistorted pulse signal and the timing characteristics of the valley bottom moment as the dual basis, the protection thresholds of overvoltage, overcurrent and overtemperature are dynamically adjusted, the amplitude stability of the undistorted pulse provides a dynamic reference for the overvoltage threshold, the basic overvoltage threshold is set to 1.1-1.2 times of the pulse amplitude, and at the same time, the voltage characteristics of the valley bottom moment are combined, if the voltage at the valley bottom moment is low, it indicates that the switching loss of the switch tube is small and the circuit stress is low, and the threshold is moderately relaxed to 1.2 times; if the voltage fluctuation at the valley bottom moment increases, it indicates that the circuit stress rises, and then the threshold is tightened to 1.1 times, which avoids false protection and ensures the voltage withstand safety of the switch tube.

[0043] According to the correlation rule of the front slope of the undistorted pulse and the load current feedforward signal, the overcurrent threshold is dynamically set, the greater the pulse front slope, the faster the load current rises, and the faster the overcurrent threshold triggers, and at the same time, the threshold curve is optimized before and after the valley bottom moment, the switch tube conduction loss is smallest at the valley bottom moment, the threshold tolerance can be temporarily relaxed to allow the current to approach the upper limit of the threshold for a short time; when deviating from the valley bottom moment, the threshold is tightened to prevent the switch tube from being damaged by overcurrent in a high loss state; All threshold adjustments are linked with the state of the optimized R and C parameters, if the R and C parameters are in high absorption capacity configuration, it indicates that the circuit has strong stress suppression capability, and the threshold dynamic range can be moderately expanded; if the parameters are in basic configuration, the threshold range is reduced to ensure the precise adaptation of protection.

[0044] The high-speed circuit control is executed in combination with the valley bottom moment: The control link with nanosecond-level response is constructed by using FPGA and high-speed drive circuit, and the timing advantage of the dynamic threshold and the valley bottom moment is converted into actual control action; within the preset timing window of the undistorted pulse signal, based on the calibrated valley bottom moment, the main switch tube is controlled to be turned on at the voltage valley bottom moment, at which time the switch tube drain-source voltage is lowest and the switching loss is smallest, and at the same time, the stable timing of the undistorted pulse is used to synchronously control the action of the clamping switch tube of the active clamping circuit, so as to ensure that the clamping voltage matches the working state of the main switch tube and further reduce the circuit stress; High-speed protection and control optimization in abnormal state: The real-time comparison is made between the circuit measured parameters such as the switch tube drain-source voltage and the load current and the dynamic threshold, if the parameters are detected to exceed the dynamic threshold, such as the drain-source voltage suddenly rising to the overvoltage threshold and the load current exceeding the overcurrent threshold, it is determined to be abnormal, and the high-speed protection action is immediately triggered: the nanosecond-level shutdown signal is output by FPGA to cut off the main switch tube drive, and at the same time, the RCD absorption circuit is controlled to strengthen energy absorption to suppress fault expansion; if the valley bottom moment deviates from the predicted range, such as the valley bottom moment is delayed due to load mutation, the control timing is quickly adjusted to advance or delay the switch tube conduction moment, so as to avoid the voltage spike and loss surge caused by conduction at the non-valley bottom moment, and at the same time, the threshold is temporarily tightened to prevent potential faults.

[0045] The working state of the switch tube, the drain-source voltage, the current, the undistorted pulse waveform integrity, the threshold trigger times and other data are collected by the high-speed sensor to determine whether the dynamic threshold is reasonable and the valley bottom moment control is accurate; if the threshold is frequently triggered but there is no actual fault, it indicates that the threshold is too strict, and the threshold dynamic range is expanded; if the fault is not triggered in time, it indicates that the threshold is too loose, and the threshold is tightened; if the valley bottom moment control causes slight distortion of the pulse, the timing calibration parameters are fine-tuned; after a preset number of pulse periods, such as 100 periods, the optimized threshold parameters and control timing are solidified to the cache, while the real-time update channel is retained, ensuring that the circuit can still quickly adapt and maintain stable control in scenarios such as load mutation and environmental temperature change.

[0046] Embodiment 2 Please refer to Figure 2 Based on Embodiment 1, Embodiment 2 of the present application further provides a pulse stable output control method of an ns-level high-repetition-rate fast pulse power supply, including the following specific steps: Step one, obtain the power supply parameters including the load impedance and the switch tube parasitic parameters by real-time sampling, and dynamically optimize the R, C parameters of the RCD absorption circuit and the active clamp circuit based on the power supply parameters; Step two, derive state information based on the power supply parameters, obtain the load current feedforward and the resonant circuit state based on the derived state information, model based on the load current feedforward and the resonant circuit state, and predict the switch tube drain-source voltage valley bottom moment; Step three, use a three-section variable impedance structure, perform wideband impedance matching based on the optimized R, C parameters of the RCD absorption circuit and the active clamp circuit, suppress the pulse front reflection distortion, and output an undistorted pulse signal; Step four, based on the undistorted pulse signal, combine the predicted switch tube drain-source voltage valley bottom moment to perform dynamic threshold adjustment and high-speed circuit control.

[0047] The above embodiments can be realized in whole or in part by software, hardware, firmware or any combination thereof. When realized by software, the above embodiments can be realized in whole or in part in the form of a computer program product. Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solutions.

[0048] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, and may be located in one place, or distributed on multiple network units. Part or all of the units can be selected to achieve the purpose of the embodiment of the present application according to actual needs.

[0049] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A pulse stable output control system of an ns-level high-repetition-rate fast pulse power supply, characterized in that, The system comprises: An adaptive absorption module, which acquires power parameters including load impedance and switch tube parasitic parameters through real-time sampling, dynamically optimizes R and C parameters of RCD absorption circuit and active clamp circuit based on the power parameters; A feedforward prediction module, which extracts derived state information according to the power parameters, acquires load current feedforward and resonant loop state based on the derived state information, models based on the load current feedforward and the resonant loop state, and predicts the switch tube drain-source voltage valley time; A multi-section variable impedance transmission module, which adopts a three-section variable impedance structure, performs wideband impedance matching based on the optimized R and C parameters of the RCD absorption circuit and the active clamp circuit, and outputs a distortionless pulse signal; A cooperative protection module, which performs dynamic threshold adjustment and high-speed circuit control based on the distortionless pulse signal and the predicted switch tube drain-source voltage valley time.

2. The pulse-stable output control system of a high-repetition-rate fast-pulse power supply at the ns level according to claim 1, characterized in that, The load impedance is obtained by collecting voltage and current signals across the load and converting the voltage and current signals into digital sequences. The switch tube parasitic parameters include drain-source parasitic capacitance, gate-source and gate-drain parasitic capacitance, and parasitic inductance.

3. The pulse-stable output control system of a high-repetition-rate fast-pulse power supply at the ns level according to claim 1, characterized in that, The process of dynamically optimizing R and C parameters of the RCD absorption circuit and the active clamp circuit is as follows: Based on the power parameters, a simulation model is used to simulate the working behavior model of the RCD absorption circuit and the active clamp circuit under different R and C parameters, an adaptive intelligent optimization algorithm is used to search for the optimal R and C combination within the preset parameter range, the actual circuit parameters are dynamically adjusted, and the actual working state of the circuit is continuously monitored, real-time data is fed back to the simulation model, and R and C parameters are iteratively optimized.

4. The pulse-stable output control system of an ns-class high-repetition-rate fast-pulse power supply according to claim 1, characterized by, The process of deriving state information from power parameters is as follows: The power parameters are preprocessed to eliminate sampling noise and time sequence deviation, effective signal components matching the power working frequency band are retained through band-pass filtering, time axis is completely aligned through time sequence synchronization calibration, and derived state information is extracted.

5. The pulse-stable output control system of an ns-class high-repetition-rate fast-pulse power supply according to claim 4, characterized by, The process of acquiring load current feedforward and resonant loop state is as follows: With the derived state information as input, an adaptive load current feedforward prediction model is constructed to output pulse driving characteristics, the dynamic change rate of the load impedance and the amplitude correlation law of the current are analyzed based on the pulse driving characteristics, the peak value, rising edge and falling edge slope, and duration of the current are predicted; The coupling characteristics of the switch tube parasitic parameters are used to correct the influence of parasitic effects on current transmission to output load current feedforward; Based on the derived state information, the resonant loop state jointly acted on by the switch tube parasitic parameters and the load impedance is analyzed, the resonant loop state frequency is calculated using the switch tube parasitic parameters, the resonant energy loss of the resonant loop state frequency and the power working frequency is judged, the current phase position is determined through the time sequence correlation characteristics of the load impedance and the switch tube parasitic parameters, and the resonant loop state is determined based on the corresponding relationship between the current phase position and the resonant energy loss.

6. The pulse-stable output control system of an ns-class high-repetition-rate fast-pulse power supply according to claim 5, characterized by, The process of modeling based on load current feedforward and resonant loop state is as follows: The peak value, rising edge or falling edge slope, and duration of the load current feedforward are extracted; The real-time resonant frequency and current phase position parameters of the resonant loop state are extracted; time axis is aligned based on a time sequence synchronization mechanism to eliminate time sequence deviation. A collaborative adaptive prediction model of load current feedforward and resonant loop state is constructed, including time sequence correlation modeling and energy change modeling; the phase correlation law of load current feedforward characteristics and resonant loop is analyzed, the time sequence coupling coefficient is quantified, the mapping relationship between current characteristics and phase change is established, and the time sequence correlation modeling is constructed; The relationship between the energy exchange process of the resonant loop and the rise and fall trend of the drain-source voltage of the switch tube is analyzed, the influence of load current feedforward on energy loss is combined, and dynamic modeling is performed based on the resonant energy state and the rise and fall trend of the drain-source voltage of the switch tube to construct an energy change model.

7. The pulse-stable output control system of a high-repetition-rate fast-pulse power supply at the ns level according to claim 6, characterized in that, The process of predicting the valley bottom time of the drain-source voltage of the switch tube is as follows: The parallel computing capability of FPGA is used to quickly calculate the time sequence correlation model and the energy change model, and the dynamic change curve of the drain-source voltage of the switch tube is output, and the calculation delay is controlled within a single pulse period; based on the voltage change curve, the time when the voltage drop rate changes from fast to slow and tends to 0 and is about to turn to rise is identified as the valley bottom time of the drain-source voltage; combined with the real-time phase position verification of the resonant loop, if there is deviation, the phase correction coefficient is fine-tuned to ensure that the valley bottom time is completely matched with the energy state of the resonant loop.

8. The pulse-stable output control system of an ns-class high-repetition-rate fast-pulse power supply according to claim 1, characterized by, The process of outputting a distortionless pulse signal is as follows: Based on the wideband impedance matching of the three-section variable impedance structure, the input matching section accurately matches the equivalent output impedance after the optimized R and C parameters of the previous stage, the middle transition section realizes impedance smooth transition according to uniform gradient, and the output matching section is real-time matched with the load impedance, and the three sections form an impedance transmission link without sudden change, and the lengths of the three transmission lines are all according to the characteristic wavelength of the corresponding working frequency band; The transmission medium is selected, a high-frequency compensation structure is added in the middle transition section, and the pulse front shape and reflection coefficient distortion index are collected in real time; the monitoring data is fed back to the FPGA control unit, the impedance values of the three-section structure and the transmission line compensation parameters are dynamically adjusted combined with the optimized R and C parameters of the previous stage and the load impedance change trend; based on the prediction time sequence of the valley bottom time of the switch tube drain-source voltage, the output pulse time sequence is calibrated through delay line fine-tuning technology to ensure that the front trigger time is accurately synchronized with the valley bottom time; After completing each pulse period, the measured waveform of the output pulse is compared with the preset distortionless standard waveform, and the distortion degree is quantified; If the distortion index exceeds the allowed range, the impedance matching algorithm and the transmission line compensation parameters are updated by DSP, the dynamic response characteristics of the three-section variable impedance structure are iteratively optimized, and finally a distortionless pulse signal is output.

9. The pulse-stable output control system of an ns-class high-repetition-rate fast-pulse power supply according to claim 1, characterized by, The process of dynamic threshold adjustment and high-speed circuit control is as follows: Based on the distortionless pulse reference characteristics and the valley bottom time sequence, the overvoltage threshold and the overcurrent threshold are dynamically adjusted, the overvoltage threshold is adjusted based on the pulse amplitude and combined with the valley bottom voltage characteristics; the overcurrent threshold is dynamically set according to the pulse front slope and the load current feedforward, the valley bottom time is relaxed, and the deviation is tightened; the overvoltage threshold and the overcurrent threshold are both adapted with the optimized R and C parameters; When working normally, within the distortionless pulse time sequence window, the main switch tube is turned on at the valley bottom time based on the valley bottom time, and the switch tube of the active clamp circuit is controlled synchronously; when abnormal, if the parameters exceed the threshold, the FPGA outputs the off signal and strengthens the RCD absorption, and if the valley bottom time deviates, the turn-on time sequence is adjusted and the threshold is temporarily tightened. Real-time monitoring control effect, deviation analysis to adjust threshold or timing calibration parameters; every preset pulse cycle, solidification optimization parameters and keep real-time update channel.

10. A pulse stable output control method of an ns-class high-repetition-rate fast pulse power supply, characterized by, It comprises the following steps: Step one, through real-time sampling to obtain power parameters, including load impedance and switch tube parasitic parameters, based on power parameter dynamic optimization RCD absorption circuit and active clamp circuit R, C parameters; Step two, according to the power parameter to extract the derived state information, based on the derived state information to obtain the load current feedforward and resonant circuit state, based on the load current feedforward and resonant circuit state modeling, to predict the switch tube drain-source voltage valley time; Step three, using three section variable impedance structure, based on the optimization of RCD absorption circuit and active clamp circuit R, C parameters for wideband impedance matching, inhibit pulse front reflection distortion, output undistorted pulse signal; Step four, based on the undistorted pulse signal, combined with the predicted switch tube drain-source voltage valley time, dynamic threshold adjustment and high-speed circuit control.

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