Continuous pulse shaping circuit based on multi-module pulse transformer and control method

Abstract

The invention discloses a continuous pulse shaping circuit based on a multi-module pulse transformer and a control method, and belongs to the technical field of pulse power. Which comprises a plurality of groups of single-module transformer units which are connected in series, and a primary charging power supply is connected in parallel with the two ends of all the single-module transformer units, and is characterized in that a bridge circuit is arranged in each group of single-module transformer unit and is connected with a primary winding of a pulse transformer; the secondary windings of the pulse transformers in all the single-module transformer units are respectively connected with a load in parallel; the bridge circuit comprises two branches which are connected in a staggered mode, the energy storage capacitor is connected between the two branches, and the two branches share the energy storage capacitor and are reversely turned off in a time-sharing mode under driving of voltages at the two ends of the energy storage capacitor. According to the continuous pulse shaping circuit based on the multi-module pulse transformer and the control method, the bridge circuit is reliably turned off through the energy storage capacitor, so that the continuous pulse shaping circuit has relatively high through-current capability and relatively low cost; and the energy storage capacitor reversely turns off the main switch thyristor, so that the utilization efficiency of energy is improved.

Description

Technical Field

[0001] A continuous pulse shaping circuit and control method based on a multi-module pulse transformer belong to the field of pulse power technology. Background Art

[0002] Pulse power technology is mainly used to generate pulse signals with short time and high energy density, and the energy density can even reach the megawatt level or higher. The main research content is to store energy and effectively transfer large energy and high power to the load. The common energy storage methods of pulse power technology are inductive energy storage, capacitive energy storage, and rotating mechanical energy storage. The inductive energy storage method has higher conversion efficiency, faster response speed, can withstand multiple charge and discharge cycles, and is small in size and light in weight compared with other forms of energy storage methods.

[0003] The power supply modes of inductive energy storage can be mainly divided into three basic modes: pulse transformer, XRAM, and Meat Grinder. Among them, the pulse transformer first stores energy in the primary inductor, and then uses the strong coupling between the primary and secondary inductors to induce a large pulse current in the secondary circuit, so as to realize the transfer of the energy stored in the primary to the load in the secondary circuit. Based on the energy storage and discharge modes of the pulse transformer, using the pulse transformer as the energy storage and pulse compression element, integrating energy storage and pulse shaping, it is easy to be integrated and modularized. During energy storage, the external power supply stores energy in the coil in the form of electromagnetic energy, which has a high energy density. When discharging, due to the mutual inductance between the primary winding and the secondary winding, the magnetic energy in the primary winding is transferred to the secondary winding, and a high-amplitude current pulse is induced in the secondary winding and output to the load.

[0004] Regarding the multi-module mode of the inductive energy storage pulse power supply, several research methods have been proposed in the prior art: (1) Literature: X. Yu and X. Chu, "STRETCH Meat Grinder With ICCOS," in IEEE Transactions on Plasma Science, vol. 41, no. 5, May 2013 and the literature by Sun Hao, Yu Xinjie, Li Zhen, etc. Analysis and Optimization of Multi-module Inductive Pulse Source System [J]. Transactions of China Electrotechnical Society, 2023, 38(02): 309-316. Tsinghua University proposed the STRETCH meat grinder circuit structure of semiconductor device reverse commutation, using thyristors to replace the main switch, and citing the semiconductor reverse carrier circuit to turn off the main switch. In the proposed multi-module inductive pulse power supply system, each single module charges and discharges the load separately, and only single-module control can be achieved, and series charging and parallel discharging between modules cannot be achieved.

[0005] (2) Reference Z. Li, H. Wu, and H. Li, "ICCOS - Based Continuous Inductive Pulse Power Circuit Topology," in IEEE Transactions on Applied Superconductivity, vol. 34, no. 8, Nov. 2024 proposed a residual energy fast recovery pulse power supply topology based on ICCOS, which combines semiconductor device reverse commutation technology with high-temperature superconducting pulse transformer technology. However, the energy of capacitor C is lost, and a pre-charge voltage needs to be set before the next charge and discharge cycle, which affects the charge and discharge flexibility. The main switch may be subjected to a higher voltage during the switching process, and corresponding measures need to be taken to limit the voltage of the pulse capacitor and the switch.

[0006] (3) A Chinese invention patent with application number 201911294494.8, application date December 16, 2019, and patent name “An inductive energy storage pulse power supply with energy recovery” proposes a technical solution, in which an inductive energy storage pulse power supply with energy recovery includes a primary winding and a secondary winding, which are coupled through a high-temperature superconducting pulse transformer. A DC voltage source is set in the primary winding, and a load and an energy recovery circuit are set in the secondary winding to increase the steepness of the discharge current, shorten the discharge time, and improve the energy utilization efficiency. The problem with this technical solution is that the use of IGBT as the main switch is relatively costly and has limited current-carrying capacity, which cannot meet the needs of different load outputs.

[0007] (4) A Chinese invention patent with application number 202410067069.X, application date January 17, 2024, and patent name “A multi-module superconducting inductor series charging and parallel discharge circuit capable of delayed parallel discharge” records a technical solution, in which a multi-module superconducting inductor energy storage pulse power supply output pulse control circuit is proposed, which is used to control the amplitude and width of the output pulse. Through the combination of IGBT switches, the series charging and parallel discharge of multi-module superconducting coupled inductors are realized, and the output pulse can be accurately modulated in amplitude and width to meet different load requirements, overcome the shortcomings of the prior art in pulse width modulation, and provide flexible pulse output capabilities. The problem with this technical solution is that the circuit involves multiple superconducting coupled inductor unit modules and a large number of switches. The current carrying capacity of using IGBT as the main switch is limited. When the load needs to output different pulse amplitudes and widths, more modules need to be stacked, resulting in a more complex circuit structure. Summary of the invention

[0008] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a continuous pulse shaping circuit and control method based on a multi-module pulse transformer, which can reliably turn off the bridge circuit through an energy storage capacitor, has a high current-carrying capacity and a low cost; the energy storage capacitor turns off the main switch thyristor reversely, improving the energy utilization efficiency.

[0009] The technical solution adopted by the present invention to solve its technical problems is as follows: This continuous pulse shaping circuit based on a multi-module pulse transformer includes multiple groups of single-module transformer units connected in series, and the primary charging power supply is connected in parallel across the two ends of all single-module transformer units. A pulse transformer is provided in each group of single-module transformer units. It is characterized in that: a bridge circuit is provided in each group of single-module transformer units, and the bridge circuit is connected to the primary winding of the pulse transformer. The secondary windings of the pulse transformers in all single-module transformer units are respectively connected in parallel with the load; the bridge circuit includes two branches connected in an interleaved manner, and an energy storage capacitor is connected between the two branches. The two branches share the energy storage capacitor and are turned off reversely in a time-sharing manner under the drive of the voltage across the energy storage capacitor; each of the two branches includes switching devices, and a coupling inductor is also connected in one of the branches.

[0010] Preferably, in one of the two branches, the first switch tube is connected in series with the coupling inductor and then connected to one end of the energy storage capacitor, and the other end of the energy storage capacitor is connected in series with the second switch tube and then connected to the same-named end of the primary winding of the pulse transformer; in the other of the two branches, a diode is connected to the connection point of the energy storage capacitor and the second switch tube, and one end of the third switch tube is connected to the connection point of the coupling inductor and the energy storage capacitor, and the other end is connected to the same-named end of the primary winding of the pulse transformer.

[0011] Preferably, a non-linear resistor for voltage limiting is also connected in parallel across the two ends of the energy storage capacitor.

[0012] Preferably, in each group of single-module transformer units, freewheeling diodes are also connected in parallel across the two ends of the bridge circuit and the primary winding of the pulse transformer.

[0013] A control method is characterized in that it includes the following steps: Step 1, charging process, forming a charging loop in each group of single-module transformer units; Step 2, after charging is completed, execute a synchronous parallel discharge process or a delayed parallel discharge process.

[0014] Preferably, the charging process includes the following steps: Step 1-1, perform pre-charging setting on the energy storage capacitor in each group of single-module pulse transformer units; Step 1-2: Trigger the conduction of the first branch. In the first cycle, utilize the recovered amount of the coupled inductor to reverse the voltage polarity of the energy storage capacitor. In the second and subsequent cycles, the capacitor charges the primary winding inductance in the positive direction, causing the polarities of the primary and secondary windings of the transformer to reverse, and rapidly transferring the remaining energy of the secondary winding to the primary winding; Step 1-3: The first branch that is triggered to conduct by the energy storage capacitor is turned off reversely. The primary charging power source is connected in series with the primary windings of the pulse transformers in all single-module transformer units to form a charging circuit.

[0015] Preferably, the synchronous parallel discharge process includes the following steps: Step 2-1: Trigger the conduction of the second branch in each group of single-module pulse transformer units. The pre-charging voltage of the energy storage capacitor turns off the first branch, forming a discharge circuit on the primary winding side of the pulse transformer; Step 2-2: Current pulses are simultaneously induced in the secondary windings of each group of single-module pulse transformer units, and they are connected in parallel to discharge the load. At the same time, the non-linear resistor jointly limits the voltage of the energy storage capacitor; after the voltage on the energy storage capacitor reaches the peak value, the third switching tube in the second branch bears a reverse voltage and turns off, forming a parallel discharge circuit for the load in each module on the secondary winding side; Step 2-3: Return to Step 1-2 in the charging process and continue to start the next cycle, and cycle in turn to generate continuous pulses.

[0016] Preferably, the delayed parallel discharge process includes the following steps: Step 3-1: Control the conduction of the second branch in all single-module transformer units except the last single-module transformer unit. The energy storage capacitor turns off the first branch therein; the primary winding current in all single-module transformer units except the last single-module transformer unit decays rapidly through the energy storage capacitor, and current pulses are simultaneously induced in the secondary windings, which are connected in parallel to discharge the load. At the same time, the non-linear resistor jointly limits the voltage of the energy storage capacitor; Step 3-2: After the reverse voltage of the energy storage capacitor in all single-module transformer units except the last single-module transformer unit reaches the peak value, drive the second branch in it to turn off and discharge in parallel on both sides of the load. The second branch in the last single-module transformer unit is turned on to form a discharge circuit, and control the second switching tube in the first branch of the last single-module transformer unit to remain on to form a freewheeling circuit; Step 3-3: Control the third switching tube in the second branch of the last single-module transformer unit to remain on. The non-linear resistor on the primary winding side of each group of single-module pulse transformer units limits the voltage of the energy storage capacitor, and current pulses are induced in the secondary windings; Step 3-4, after the voltage of the energy storage capacitor in the last single-module pulse transformer unit reaches the peak value, the third switch tube in the second branch bears a reverse voltage and turns off, and a parallel discharge circuit for the load is formed in each module on the secondary winding side; Step 3-5, return to Step 1-2, continue to start the next cycle, and cycle in turn to generate continuous pulses.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: The continuous pulse shaping circuit and control method based on a multi-module pulse transformer can reliably turn off the bridge circuit through the energy storage capacitor, have a high current-carrying capacity and a low cost; the energy storage capacitor reversely turns off the main switch thyristor, improving the energy utilization efficiency.

[0018] Through the continuous pulse shaping circuit and control method based on a multi-module pulse transformer, the remaining energy is recovered and applied in the next discharge cycle, reducing the charging time in the next charge-discharge cycle. A freewheeling current is formed through the unidirectional conduction branch before the charging command in the next charge-discharge cycle arrives, improving the flexibility of charge and discharge for the multi-module pulse transformer continuous pulse shaping circuit. The inductor in each single-module pulse transformer unit transfers the stored energy to the pulse capacitor before the start of the next charge-discharge cycle; the pulse capacitor and the non-linear resistor in each single-module pulse transformer unit jointly limit the voltage of the main switch thyristor, enhancing the current-carrying capacity of the main switch.

[0019] Through the continuous pulse shaping circuit and control method based on a multi-module pulse transformer, the coupled inductors are charged in series, and the synchronous parallel discharge mode and the delayed parallel discharge mode can be selected according to the requirements of the load for the pulse waveform. During the discharge process, the main switch thyristor is turned off by providing a reverse voltage drop through the pulse capacitor, and the instantaneous voltage impact of the open circuit switch is limited by the pulse capacitor, and the voltage amplitude of the short circuit switch is limited by the non-linear voltage limiting resistor. At the end of the discharge, by using the pulse capacitor again to provide a forward voltage drop to the primary winding of the pulse transformer, the remaining energy in the secondary winding is recovered to the primary winding and automatically used for the next charge-discharge cycle, improving the efficiency and flexibility of the system.

[0020] The continuous pulse shaping circuit and control method based on a multi-module pulse transformer can recover the remaining energy of the primary winding and the secondary winding accordingly and apply it in the next charge-discharge cycle, reducing the charging time in the next charge-discharge cycle, improving the charging efficiency and the energy transmission efficiency, and at the same time avoiding a large amount of remaining energy in the primary winding.

[0021] The pulse transformer uses a capacitor and a non-linear resistor to jointly limit the voltage, so that no high-amplitude voltage pulse appears during the instantaneous discharge of the primary winding, reducing the requirements of the system for the open circuit switch.

[0022] Each module of the continuous pulse forming circuit based on a multi-module pulse transformer is provided with a freewheeling diode, which can be grouped for step-by-step delayed parallel discharge. Description of the Drawings

[0023] Figure 1 FIG. is the circuit schematic diagram of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0024] Figure 2 FIG. is the schematic diagram of the synchronous parallel discharge process of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0025] Figures 3 - 8 FIG. is the circuit schematic diagram of the synchronous parallel discharge process of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0026] Figure 9 FIG. is the waveform diagram of the primary winding and load current in the parallel simultaneous discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0027] Figure 10 FIG. is the waveform diagram of the primary winding current in the parallel simultaneous discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0028] Figure 11 FIG. is the pulse waveform diagram of the load current in the parallel simultaneous discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0029] Figure 12 FIG. is the schematic diagram of the delayed parallel discharge process of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0030] Figures 13 - 17 FIG. is the circuit schematic diagram of the delayed parallel discharge process of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0031] Figure 18 FIG. is the waveform diagram of the primary winding and load current in the grouped delayed parallel discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0032] Figure 19 FIG. is the waveform diagram of the primary winding current in the grouped delayed parallel discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer.

[0033] Figure 20 FIG. is the pulse waveform diagram of the load current in the grouped delayed parallel discharge mode of the continuous pulse forming circuit based on a multi-module pulse transformer. Detailed Embodiments

[0034] Figures 1 - 20 This is the best embodiment of the present invention. The following combines with the attached drawings Figures 1 - 20Further description of the present invention.

[0035] A continuous pulse shaping circuit based on a multi-module pulse transformer, including a plurality of single-module transformer units. The plurality of single-module transformer units share a primary charging power supply. Each group of single-module transformer units includes a plurality of switching devices S n-1 ~S n-3 , a freewheeling diode D n-1 and a pulse transformer M n , where n is the number of single-module transformer units. The switching devices S n-1 ~S n-3 are implemented by thyristors, so the on-off control can be conveniently realized and the reliability is high. The primary winding of the pulse transformer is wound with superconducting material, and the secondary winding is wound with normal conducting material.

[0036] Specifically: In each group of single-module pulse transformer units, the cathode of the freewheeling diode D n-2 is simultaneously connected to the anode of the thyristor S n-2 and the anode of the diode D n-1 . The cathode of the thyristor S n-2 is connected in series with an inductor L cn and then simultaneously connected to one end of a capacitor C n , one end of a non-linear resistor R n and the anode of the thyristor S n-3 . The cathode of the diode D n-1 is simultaneously connected to the other end of the capacitor C n , the other end of the non-linear resistor R n and the anode of the thyristor S n-1 . The cathodes of the thyristor S n-3 and the thyristor S n-1 are simultaneously connected to the same-named end of the primary winding L n in the pulse transformer M n-1 . The opposite-named end of the primary winding L n in the pulse transformer M n-1 is connected to the anode of the freewheeling diode D n-2 . In the secondary winding of the pulse transformer M n , the opposite-named end of the secondary winding L n-2 is connected in series with a load R L and then connected to the anode of the diode D n-3 . The cathode of the diode D n-3 is connected to the same-named end of the secondary winding L n-2 .

[0037] The opposite-named end of the primary winding L n-1 is simultaneously connected to the anode of the thyristor S （n+1）-2The anode realizes the series connection of multiple single-module pulse transformer units, and the primary charging power supply is connected in parallel across both ends of the multiple single-module pulse transformer units connected in series.

[0038] As Figure 1 shown, taking three groups (n = 1, 2, 3) of single-module transformer units as an example for detailed description: In the first group of single-module transformer units, the cathode of the freewheeling diode D 1-2 is simultaneously connected to the anode of the thyristor S 1-2 and the anode of the diode D 1-1 . The cathode of the thyristor S 1-2 is connected in series with the inductor L c1 and then simultaneously connected to one end of the capacitor C 1 , one end of the non-linear resistor R 1 and the anode of the thyristor S 1-3 . The cathode of the diode D 1-1 is simultaneously connected to the other end of the capacitor C 1 , the other end of the non-linear resistor R 1 and the anode of the thyristor S 1-1 . The thyristor S 1-3 and the thyristor S 1-1 are simultaneously connected to the same-named end of the primary winding L 1 in the pulse transformer M 1-1 . The opposite-named end of the primary winding L 1 in the pulse transformer M 1-1 is connected to the anode of the freewheeling diode D 1-2 . In the secondary winding of the pulse transformer M 1 , the opposite-named end of the secondary winding L 1-2 is connected in series with the load R L and then connected to the anode of the diode D 1-3 . The cathode of the diode D 1-3 is connected to the same-named end of the secondary winding L 1-2 .

[0039] The opposite-named end of the primary winding L 1-1 is simultaneously connected to the anode of the thyristor S 2-2 in the second group of single-module pulse transformer units. In the second group of single-module transformer units, the cathode of the freewheeling diode D 2-2 is simultaneously connected to the anode of the thyristor S 2-2 and the anode of the diode D 2-1 . The cathode of the thyristor S 1-2 is connected in series with the inductor L c2 and then simultaneously connected to one end of the capacitor C 2 , one end of the non-linear resistor R 2 and the anode of the thyristor S 2-3 . The cathode of the diode D 2-1The cathode of is simultaneously connected to capacitor C 2 The other end, non-linear resistor R 2 The other end and thyristor S 2-1 The anode of thyristor S 2-3 And thyristor S 2-1 The cathode of is simultaneously connected to the primary winding L 2 In pulse transformer M 2-1 The corresponding end of, pulse transformer M 2 The primary winding L in 2-1 The opposite end of is connected to freewheeling diode D 2-2 The anode of. In pulse transformer M 2 In the secondary winding, the secondary winding L 2-2 The opposite end of is connected in series with load R L And then connected to the anode of diode D 2-3 The anode of diode D 2-3 The cathode of is connected to the corresponding end of the secondary winding L 2-2 Corresponding end.

[0040] The primary winding L 2-1 The opposite end of is simultaneously connected to the anode of thyristor S in the third group of single-module pulse transformer units 3-2 In the third group of single-module transformer units, the cathode of freewheeling diode D 3-2 Is simultaneously connected to the anode of thyristor S 3-2 And the anode of diode D 3-1 The anode of thyristor S 1-2 The cathode of is connected in series with inductor L c3 And then simultaneously connected to one end of capacitor C 3 One end of non-linear resistor R 3 One end and the anode of thyristor S 3-3 The anode of diode D 3-1 The cathode of is simultaneously connected to the other end of capacitor C 3 The other end of non-linear resistor R 3 One end and the anode of thyristor S 3-1 The anode of thyristor S 3-3 And thyristor S 3-1 The cathode of is simultaneously connected to the corresponding end of the primary winding L 3 In pulse transformer M 3-1 The corresponding end of, pulse transformer M 3 The primary winding L in 3-1 The opposite end of is connected to freewheeling diode D 3-2 The anode of. In pulse transformer M 3 In the secondary winding, the secondary winding L 3-2 The opposite end of is connected in series with load R L And then connected to the anode of diode D 3-3 The anode of diode D 3-3The secondary winding L connected to the cathode 3-2 Polarity mark.

[0041] The primary charging power supply U s The positive pole of which is connected to the anode of the thyristor S in the first group of single-module pulse transformer units 1-2 The primary charging power supply U s The negative pole of which is connected to the non-polarity mark of the primary winding L of the pulse transformer M in the third group of single-module pulse transformer units 3 The primary winding L 3-1 Of the non-polarity mark.

[0042] Based on Figure 1 The continuous pulse shaping circuit based on the multi-module pulse transformer shown, according to different discharge modes, can be divided into a synchronous parallel discharge mode and a delayed parallel discharge mode during its working process.

[0043] As Figure 2 Shown, the synchronous parallel discharge process includes the following steps:[[]]END]] Step a, pre-charge the capacitors in each module; Set the pre-charge for the capacitor C in each group of single-module pulse transformer units n Pre-charge the capacitor before triggering the conduction power supply as Figure 3 Shown, after the capacitor voltage pre-charge is completed, enter stage b.

[0044] Step b, trigger the charging switch to conduct, reverse the capacitor polarity, and recover and transfer the energy in each module; Trigger the switching devices S n-1 , S n-2 In the first cycle, use the inductor L cn To recover part of the energy to reverse the voltage polarity of the capacitor C n In the second and subsequent cycles, trigger the charging switch S n-1 To conduct, the capacitor charges the primary winding inductor L n-1 Forward, reverse the polarities of the primary and secondary windings of the transformer, and quickly transfer the remaining energy of the secondary winding to the primary winding, as Figure 4 Shown.

[0045] Step c, form a series charging circuit in the primary winding; The positive voltage on the capacitor C n Forces the switch S n-2 To turn off, the diode D n-1 Conducts, so that the primary charging power supply U s Charges the superconducting coupling inductor (secondary winding) L 1-1 ~L 3-1 In series, the primary charging power supply U sThe positive electrode of 1-1 - thyristor S 1-1 - coupled inductor L 1-1 - diode D 2-1 - thyristor S 2-1 - coupled inductor L 2-1 - diode D 3-1 - thyristor S 3-1 - coupled inductor L 3-1 forms a charging circuit with the negative electrode of the primary charging power supply U s , as Figure 5 shown.

[0046] Step d, form a discharge circuit in the primary winding of the pulse transformer; Trigger the switching device S in each single - module pulse transformer unit n-3 to conduct. The pre - charging voltage of the capacitor C n forces the switch S n-1 to turn off. The discharge circuit on the primary winding side of the pulse transformer: U s 's positive electrode - diode D 1-1 - capacitor C 1 - thyristor S 1-3 - inductor L 1-1 - diode D 2-1 - capacitor C 2 - thyristor S 2-3 - coupled inductor L 2-1 - diode D 3-1 - capacitor C 3 - thyristor S 3-3 - coupled inductor L 3-1 forms a circuit with the negative electrode of the primary charging power supply U s , as Figure 6 shown.

[0047] Step e, induce an induced current in the secondary winding of the pulse transformer and discharge in parallel to the load; The secondary windings L of each single - module pulse transformer unit n-2 simultaneously induce current pulses and discharge in parallel to the load R L . At the same time, the non - linear resistor R n and the capacitor C n jointly limit the voltage of the coupled inductor, as Figure 7 shown. After the voltage on the capacitor C n reaches the peak value, the diode D n-1 cannot conduct under the reverse voltage. The switching device S n-3 is forced to turn off under the reverse voltage. At this time, in each module on the secondary winding side, the inductor L n-2 - load - diode D n-3 form a parallel discharge circuit, asFigure 8 as shown

[0048] Step f: Return to step b. After the operation process of step e is completed, return to step b and continue to start the next cycle, and cycle in turn to generate continuous pulses. The result of the synchronous parallel discharge mode is as Figures 9 - 11 shown

[0049] as Figure 12 shown, the delayed parallel discharge process includes the following steps: Step a': Pre-charge the capacitors in each module; Set the pre-charge of the capacitor C in each single-module pulse transformer unit. Before triggering and turning on the power supply, pre-charge the capacitor as n shown. After the capacitor voltage pre-charge is completed, enter phase b. Figure 3 shown

[0050] Step b': Trigger the charging switch to turn on, reverse the polarity of the capacitor, and recover and transfer the energy in each module; Trigger the switching devices S in each single-module pulse transformer unit n-1 and S n-2 to turn on. In the first cycle, use the inductor L cn to recover a part of the energy to reverse the voltage polarity of the capacitor C n . In the second and subsequent cycles, trigger the charging switch S n-1 to turn on. The capacitor charges the primary winding inductor L n-1 positively, reverse the polarities of the primary and secondary windings of the transformer, and quickly transfer the remaining energy of the secondary winding to the primary winding, as Figure 4 shown

[0051] Step c': Form a series charging circuit in the primary winding; The positive voltage on the capacitor C n forces the switch S n-2 to turn off, and the diode D n-1 turns on, so that the primary charging power supply U s charges the superconducting coupling inductor (secondary winding) L 1-1 ~L 3-1 in series. The positive pole of the primary charging power supply U s sequentially passes through the diode D 1-1 - thyristor S 1-1 - coupling inductor L 1-1 - diode D 2-1 - thyristor S 2-1 - coupling inductor L 2-1 - diode D 3-1 - thyristor S 3-1 - coupling inductor L 3-1 and the primary charging power supply Us A charging circuit is formed between the negative electrodes as shown in Figure 5 .

[0052] Step d': Control the 1st to the (n - 1)th modules to conduct. The primary winding currents of the 1st to the (n - 1)th modules rapidly decay through the capacitors, and current pulses are simultaneously induced in the secondary windings, discharging in parallel to the load.

[0053] Trigger the switching devices S in each group of single-module pulse transformer units and in every second group of single-module pulse transformer units 1-3 、S 2-3 to conduct. The pre-charging voltages of capacitors C 1 and C 2 force the switching devices S 1-1 、S 2-1 to turn off, and the primary winding side circuit is as shown in Figure 13 : The positive electrode of the primary charging power supply U s - diode D 1-1 - capacitor C 1 - thyristor S 1-3 - coupled inductor L 1-1 - diode D 2-1 - capacitor C 2 - thyristor S 2-3 - coupled inductor L 2-1 - diode D 3-1 - thyristor S 3-1 - coupled inductor L 3-1 and the negative electrode of the primary charging power supply U s . The primary winding currents in each group of single-module pulse transformer units and in every second group of single-module pulse transformer units rapidly decay through the capacitors, current pulses are simultaneously induced in the secondary windings, discharging in parallel to the load, and at the same time, the non-linear resistor and the capacitor jointly limit the voltage of the coupled inductor as shown in Figure 14 .

[0054] Step e': The 1st to the (n - 1)th modules discharge in parallel to the load and a freewheeling circuit is formed in the nth module; Capacitors C 1 and C 2 reach the peak reverse voltage, and S 1-3 、S 2-3 are forced to turn off by the reverse voltage. At this time, Module 1 and Module 2 discharge in parallel on both sides of the load, and an inductor - load - discharge diode in the module forms a discharge circuit; The thyristor S 3-1 remains conducting, and the inductor L 3-1 - diode D d3 - diode D 3-1 - thyristor S 3-1 are connected in series in turn to form a freewheeling circuit as shown in Figure 15As shown, after a certain time delay, it enters step f'.

[0055] Step f': Induce a current pulse in the secondary winding of the nth module. Trigger switch S 3-3 to conduct. In the primary winding side circuit of each three - unit single - module pulse transformer unit, as Figure 16 shown, they are in sequence: inductor L 3-1 - free - wheeling diode D d3 - diode D 3-1 - capacitor C 3 - thyristor S 3-3 ; In each single - module pulse transformer unit, the non - linear resistor and capacitor on the primary winding side appropriately limit the voltage of the coupled inductor, and a current pulse is induced in the secondary winding. As Figure 17 shown, after a certain time delay, it enters step g.

[0056] Step g': Form a discharge circuit in the secondary winding of the nth module. In each single - module pulse transformer unit, after the voltage on capacitor C 3 reaches the peak value, diode D 3-1 cannot conduct under the reverse voltage, and S 3-3 is forced to turn off under the reverse voltage. At this time, in the secondary winding side module 3, inductor L 3-2 - load - diode D 3 forms a discharge circuit, as Figure 8 shown.

[0057] Step h': Return to step b'. After the operation process of step g' is completed, return to step b' and continue to start the next cycle, and cycle in sequence to generate continuous pulses. The result of the delay parallel discharge mode is as Figures 18 - 20 shown.

[0058] The above - mentioned are only the preferred embodiments of the present invention, and are not limitations to the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A continuous pulse shaping circuit based on a multi-module pulse transformer, comprising a plurality of groups of single-module transformer units connected in series, a primary charging power source connected in parallel at both ends of all the single-module transformer units, and a pulse transformer being arranged in each group of the single-module transformer units, characterized in that: A bridge circuit is arranged in each group of single-module transformer units, and the bridge circuit is connected to the primary winding of the pulse transformer. The secondary windings of the pulse transformers in all single-module transformer units are respectively connected in parallel with the load; the bridge circuit includes two branches connected in an interlaced manner, and the energy storage capacitor is connected between the two branches. The two branches share the energy storage capacitor and are reversely shut down in time-sharing manner under the drive of the voltage across the energy storage capacitor; the two branches respectively include switching devices, and a coupling inductor is also connected to one of the branches.

2. The continuous pulse shaping circuit based on a multi-module pulse transformer according to claim 1, characterized in that: In one of the two branches, the first switch tube is connected in series with the coupling inductor and then connected to one end of the energy storage capacitor, and the other end of the energy storage capacitor is connected in series with the second switch tube and then connected to the same end of the primary winding of the pulse transformer; in the other of the two branches, the diode is connected to the connection between the energy storage capacitor and the second switch tube, one end of the third switch tube is connected to the connection between the coupling inductor and the energy storage capacitor, and the other end is connected to the same end of the primary winding of the pulse transformer.

3. The continuous pulse shaping circuit based on a multi-module pulse transformer according to claim 1, characterized in that: A nonlinear resistor for limiting the voltage of the energy storage capacitor is connected in parallel at both ends of the energy storage capacitor.

4. The continuous pulse shaping circuit based on a multi-module pulse transformer according to claim 1, characterized in that: In each group of single-module transformer units, a freewheeling diode is connected in parallel between the bridge circuit and both ends of the primary winding of the pulse transformer.

5. A control method implemented by the continuous pulse shaping circuit based on a multi-module pulse transformer according to any one of claims 1 to 4, characterized in that: The steps include: Step 1, charging process, forming a charging loop in each group of single-module transformer units; Step 2: After charging is completed, a synchronous parallel discharge process or a delayed parallel discharge process is performed.

6. The control method according to claim 5, characterized in that: The charging process includes the following steps: Step 1-1, pre-charging the energy storage capacitor in each group of single-module pulse transformer units; Step 1-2, triggering the first branch to conduct, in the first cycle, the coupling inductor is used to recover the voltage polarity of the energy storage capacitor, and in the second and subsequent cycles, the capacitor charges the primary winding inductance in a positive direction, so that the polarity of the primary winding and the secondary winding of the transformer is reversed, so that the residual energy of the secondary winding is quickly transferred to the primary winding; In step 1-3, the first branch that is triggered to turn on when the energy storage capacitor is reversely turned off, and the primary charging power supply is connected in series with the primary winding of the pulse transformer in all single-module transformer units to form a charging circuit.

7. The control method according to claim 6, characterized in that: The synchronous parallel discharge process includes the following steps: Step 2-1, triggering the second branch in each group of single-module pulse transformer units to conduct, the pre-charge voltage of the energy storage capacitor turns off the first branch, and a discharge loop is formed on the primary winding side of the pulse transformer; Step 2-2, the secondary windings of each group of single-module pulse transformer units simultaneously induce current pulses, which are discharged in parallel to the load, and the nonlinear resistors jointly limit the voltage of the energy storage capacitors; after the voltage on the energy storage capacitors reaches a peak value, the third switch tube in the second branch is subjected to a reverse voltage and is turned off, and a parallel discharge loop for the load is formed in each module on the secondary winding side; Step 2-3, returns to step 1-2 in the charging process, continues to start the next cycle, and cycles in sequence to generate continuous pulses.

8. The control method according to claim 6, characterized in that: The delayed parallel discharge process includes the following steps: Step 3-1, control the second branch of all single-module transformer units except the last single-module transformer unit to be turned on, and the energy storage capacitor turns off the first branch; the primary winding current of all single-module transformer units except the last single-module transformer unit decays rapidly through the energy storage capacitor, and the secondary winding simultaneously induces a current pulse, which is discharged in parallel to the load, and at the same time, the nonlinear resistor jointly limits the voltage of the energy storage capacitor; Step 3-2, after the reverse voltage of the energy storage capacitor in all single-module transformer units except the last single-module transformer unit reaches a peak value, the second branch therein is driven to be turned off and discharged in parallel on both sides of the load, the second branch in the last single-module transformer unit is turned on to form a discharge loop, and the second switch tube in the first branch of the last single-module transformer unit is controlled to remain turned on to form a freewheeling loop; Step 3-3, control the third switch tube in the second branch of the last single-module transformer unit to remain turned on, the nonlinear resistor on the primary winding side of each group of single-module pulse transformer units limits the voltage of the energy storage capacitor, and the secondary winding induces a current pulse; Step 3-4, after the voltage of the energy storage capacitor in the last single-module pulse transformer unit reaches the peak value, the third switch tube in the second branch is subjected to the reverse voltage and is turned off, and a parallel discharge loop for the load is formed in each module on the secondary winding side; Step 3-5, return to step 1-2, continue to start the next cycle, and cycle in sequence to generate continuous pulses.

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