High-voltage pulse generation circuit based on pre-boost structure, working method and application

Abstract

The invention discloses a high-voltage pulse generation circuit based on a front boost structure, a working method and application, and belongs to the field of high-voltage pulse power supplies, the high-voltage pulse generation circuit comprises a direct-current power supply, a front Sepic boost circuit and a pulse forming module which are connected in sequence, and the pulse forming module comprises a plurality of cascaded Marx high-voltage pulse circuits. Therefore, the direct-current power supply is boosted by the aid of the front Sepic booster circuit, boosted electric energy is transmitted to the pulse forming module, and high-voltage pulses are formed on a load by the aid of parallel charge pump voltage and series discharge of the Marx high-voltage pulse circuit. By adopting the high-voltage pulse generation circuit based on the pre-boost structure, the working method and the application, a traditional Marx circuit is optimized through the Sepic boost converter, the voltage gain is improved, the number and cost of devices are reduced, the voltage stress of the devices is reduced, the system efficiency is improved, the power density is increased, the reliability is improved, and the service life of the circuit is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage pulse power supplies, and particularly to a high-voltage pulse generation circuit, a working method and an application based on a pre-boost structure. Background Art

[0002] As a classic all-solid-state power pulse generator, the Marx circuit mainly realizes the parallel charging and series discharging processes of capacitors by controlling the on-off of switching tubes, and then generates high-voltage pulses on the load.

[0003] With the rapid development of semiconductor technology, the Marx circuit with small volume and stable output waveform has been widely used in many fields such as biomedicine, industrial waste treatment, electrostatic precipitation, microwave weapons, and plasma research. However, with the continuous progress of each application field, higher requirements are put forward for the performance of pulse power supplies, especially in terms of high voltage gain, miniaturization, and high power density.

[0004] At present, to meet the demand for high voltage gain of pulse power supplies, there are mainly two common solutions. One is to increase the number of stages of the charge and discharge unit of the Marx generator. Theoretically, the increase in the number of stages can improve the voltage gain. However, in practical applications, as the number of stages of the Marx circuit increases, the number of switching devices in the circuit also increases, which will not only cause a significant increase in the overall switching loss but also rapidly reduce the circuit efficiency. At the same time, more devices mean a larger circuit volume and higher cost, and these factors seriously restrict the further application of the Marx circuit in the field of high-voltage pulses.

[0005] Another method is to increase the voltage level of the capacitors in the charge and discharge unit of the Marx generator to improve the overall voltage gain of the circuit. This method can reduce the circuit volume, reduce the power loss of switching tubes, and reduce the cost to a certain extent. However, this method also faces some technical challenges in actual operation, such as how to safely and effectively increase the capacitor voltage and the impact on the circuit stability and reliability after the increase. Summary of the Invention

[0006] The object of the present invention is to provide a high-voltage pulse generation circuit, a working method and an application based on a pre-boost structure to solve the above technical problems.

[0007] To achieve the above object, the present invention provides a high-voltage pulse generation circuit based on a pre-boost structure, comprising a DC power supply, a pre-Sepic boost circuit, and a pulse forming module connected in sequence. Among them, the pulse forming module includes a plurality of cascaded Marx high-voltage pulse circuits, thereby realizing the boosting of the DC power supply by the pre-Sepic boost circuit and transmitting the boosted electrical energy to the pulse forming module. The parallel charging pump voltage and series discharge of the Marx high-voltage pulse circuit are used to form a high-voltage pulse on the load.

[0008] Preferably, the pre-Sepic boost circuit includes an inductor , an inductor , a capacitor , and a switching transistor . One end of the inductor is connected to the positive electrode of the DC power supply , and the other end is sequentially connected to the negative electrode of the DC power supply through the capacitor and the inductor . A switching transistor is connected between the inductor and the capacitor . The source electrode of the switching transistor is connected between the negative electrode of the DC power supply and the inductor .

[0009] Preferably, the pulse forming module includes cascaded Marx high-voltage pulse circuits. The -th stage Marx high-voltage pulse circuit includes a capacitor , a diode , a thyristor , and a switching transistor . And ; The anode of the thyristor is connected between the capacitor and the inductor . The anode of the thyristor is connected to the anode of the diode through the capacitor . The cathode of the diode is connected between the inductor and the cathode of the switching transistor . And the diodes , , to are connected in series in the same phase in the same loop; The drain electrode of the switching transistor is connected to the thyristor and capacitor Between them, the source electrode of the switching transistor is connected to the cathode of the diode and the diode .

[0010] Preferably, the switching transistor is an IGBT or a MOSFET, and the switching transistor is an IGBT or a MOSFET.

[0011] A working method of a high-voltage pulse generation circuit based on a pre-boost structure includes an inductor charging preparation stage, a capacitor charging and voltage pumping stage, a capacitor supplementary charging stage, and a high-voltage pulse output stage that are executed cyclically; Among them, the steps of the inductor charging preparation stage are as follows: Turn on the switching transistor , and at the same time turn off the switching transistor and the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor through the switching transistor , and the capacitor charges the inductor through the switching transistor ; The steps of the capacitor charging and voltage pumping stage are as follows: Turn off the switching transistor and the switching transistor , turn on and control the thyristor . At this time, the diode is turned on, and the DC power supply and the inductor storing energy charge the capacitor at the same time to increase the voltage of the capacitor , and the inductor storing energy, the inductor storing energy, and the DC power supply charge the capacitor at the same time to achieve voltage pumping until the voltage of the capacitor reaches the maximum capacitor voltage . At this time, the anode current of the thyristor is lower than the holding current, and the thyristor is turned off; The steps of the capacitor supplementary charging stage are as follows: Turn off the switching transistor , the switching transistor and the thyristor . At this time, the diode is cut off, and the DC power supply charges the capacitor through the inductor ... Charge to further increase the capacitance Voltage; The steps of the high-voltage pulse output stage are as follows: Turn on the switching transistor and the switching transistor , turn off the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor , and the capacitor charges the inductor through the switching transistor . At the same time, the capacitor discharges through the switching transistor in series to the load, thereby forming a high-voltage pulse on the load.

[0012] Application of the high-voltage pulse generation circuit based on the pre-boost structure in electrostatic precipitation, wastewater treatment, pulsed electric field sterilization, or biological tissue ablation.

[0013] Therefore, the present invention adopts the above-mentioned high-voltage pulse generation circuit, working method, and application based on the pre-boost structure, and the beneficial effects are as follows: 1. High voltage gain: The capacitor of the Marx high-voltage pulse circuit is boosted by using the pre-boost Sepic circuit. Compared with the traditional Marx circuit, the voltage gain can be increased several times without changing the number of stages, meeting the high-voltage requirements (meeting the requirement of obtaining a high voltage gain without increasing the number of circuit stages in the Marx high-voltage pulse circuit, and obtaining a high-voltage pulse output on the basis of consuming fewer power electronic switching devices); 2. Cost reduction: The number of power electronic switching devices can be significantly reduced, reducing the cost of the pulse generator; at the same time, due to the reduction of the voltage stress of the devices, devices with lower withstand voltage and lower cost can be selected, further saving costs; 3. Improvement of system performance: The voltage stress of the devices is reduced, avoiding the withstand voltage problem of power electronic switching devices, improving the reliability of the pulse circuit; ensuring that the devices work under low voltage stress for a long time, extending the life of the overall circuit; improving the system efficiency and power density, and reducing the volume of the pulse power supply.

[0014] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0015] Figure 1 is the schematic diagram of the high-voltage pulse generation circuit based on the pre-boost structure described in the present invention; Figure 2 is the circuit structure comparison diagram of the simulation experiment described in the present invention, where (a) is the schematic diagram of the traditional 4-stage Marx pulse circuit, and (b) is the schematic diagram of the 4-stage Marx high-voltage pulse circuit described in the present invention; Figure 3 This is the timing diagram of the PWM control signal for the switching device in the simulation experiment of the present invention. Among them, (a) is the timing diagram of the PWM control signal for the switching transistor , (b) is the timing diagram of the PWM control signal for the thyristor , (c) is the timing diagram of the PWM control signal for the switching transistor ; Figure 4 This is the working principle diagram of the simulation experiment of the present invention. Among them, (a) is the schematic diagram of the inductor charging preparation stage, (b) is the schematic diagram of the capacitor charging and voltage pumping stage, (c) is the schematic diagram of the capacitor supplementary charging stage, and (d) is the schematic diagram of the high-voltage pulse output stage; Figure 5 This is the simulation current and voltage waveform diagram of the traditional 4-stage Marx pulse circuit in the simulation experiment of the present invention; Figure 6 This is the simulation current and voltage waveform diagram of the 4-stage Marx high-voltage pulse circuit of the present invention in the simulation experiment of the present invention; Figure 7 This is the output pulse comparison diagram of the 4-stage Marx high-voltage pulse circuit of the present invention and the traditional 4-stage Marx pulse circuit in the simulation experiment of the present invention; Figure 8 This is the voltage stress diagram borne by the switching device in the simulation experiment of the present invention. Among them, (a) is the voltage stress diagram borne by the diode , (b) is the voltage stress diagram borne by the switching transistor , (c) is the voltage stress diagram borne by the switching transistor , (d) is the voltage stress diagram borne by the thyristor . Detailed implementation manners

[0016] In order to make the purpose, technical solutions and advantages of the embodiments disclosed in the present invention clearer, the following further elaborates on the embodiments of the present invention in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not used to limit the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope protected by this application. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end.

[0017] It should be noted that the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or server that includes a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to those processes, methods, products, or devices.

[0018] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0019] As Figure 1 shown, a high-voltage pulse generation circuit based on a pre-boost structure includes a DC power supply, a pre-Sepic boost circuit, and a pulse forming module connected in sequence. Among them, the pulse forming module includes a plurality of cascaded Marx high-voltage pulse circuits, thereby realizing the boosting of the DC power supply by the pre-Sepic boost circuit and transmitting the boosted electrical energy to the pulse forming module. The parallel charging pump voltage and series discharge of the Marx high-voltage pulse circuit are used to form a high-voltage pulse on the load.

[0020] Specifically, the pre-Sepic boost circuit includes an inductor , an inductor , a capacitor , and a switching tube . One end of the inductor is connected to the positive pole of the DC power supply , and the other end is connected to the negative pole of the DC power supply through the capacitor and the inductor in sequence. A switching tube is connected between the inductor and the capacitor . The drain of the switching tube is connected to the source of the DC power supply and the inductor .

[0021] The pulse forming module includes cascaded Marx high-voltage pulse circuits. The th stage Marx high-voltage pulse circuit includes a capacitor , a diode , a thyristor , and a switching tube . And ; the anode of the thyristor is connected between the capacitor and the inductor . The anode of the thyristor is connected to the anode of the diode through the capacitor . The cathode of is connected to the inductor and the switch tube , diode , diode to diode are connected in series in the same circuit in phase; the drain of the switch tube is connected between the thyristor and the capacitor , and the source of the switch tube is connected between the cathode of the diode and the diode .

[0022] The switch tube is an IGBT or a MOSFET, and the switch tube is an IGBT or a MOSFET. It should be noted that the selection of the above devices is only for illustration and should not be construed as a limitation of this application.

[0023] A working method of a high-voltage pulse generation circuit based on a pre-boost structure includes an inductor charging preparation stage, a capacitor charging and voltage pumping stage, a capacitor supplementary charging stage, and a high-voltage pulse output stage that are cyclically executed; Among them, the steps of the inductor charging preparation stage are as follows: turn on the switch tube , and at the same time turn off the switch tube and the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor through the switch tube , and the capacitor charges the inductor through the switch tube ; The steps of the capacitor charging and voltage pumping stage are as follows: turn off the switch tube and the switch tube , turn on and control the thyristor . At this time, the diode is turned on, and the DC power supply and the inductor storing energy charge the capacitor at the same time to increase the voltage of the capacitor , and the inductor storing energy, the inductor storing energy, and the DC power supply charge the capacitor at the same time to achieve voltage pumping until the voltage of the capacitor reaches the maximum capacitor voltage , at this time the thyristor When the anode current is lower than the holding current, the thyristor turns off; The steps of the capacitor supplementary charging stage are as follows: Turn off the switching transistor , switching transistor and thyristor . At this time, the diode is cut off, and the DC power supply charges the capacitor , inductor through the inductor , further increasing the voltage of the capacitor ; The steps of the high-voltage pulse output stage are as follows: Turn on the switching transistor and switching transistor , turn off the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor . The capacitor charges the inductor through the switching transistor . At the same time, the capacitor discharges in series to the load through the switching transistor , thereby forming a high-voltage pulse on the load.

[0024] Simulation experiment

[0025] As Figures 2 - 7 shown, the simulation parameters are set as follows: the number of circuit stages is 4, the DC input power supply voltage , the output pulse voltage , the output pulse frequency , the output pulse width , the output pulse instantaneous power . Taking the traditional 4-stage Marx pulse circuit as a comparative example, the results are as Figure 5 shown. It can be seen that when the traditional 4-stage Marx pulse circuit and the 4-stage Marx high-voltage pulse circuit described in the present invention have the same input voltage and output pulse width, the capacitor voltage and the overall output pulse voltage of the 4-stage Marx high-voltage pulse circuit in the present invention are higher than those of the traditional 4-stage Marx pulse circuit. And the voltage gain of the present invention is significantly higher than that of the traditional 4-stage Marx pulse circuit.

[0026] As Figure 8 shown, it can be seen that the switching devices (diode , switching transistor , switching transistor and thyristor ) in the present invention do not bear the high output pulse voltage.

[0027] Application of a high-voltage pulse generation circuit based on a pre-boost structure in electrostatic dust removal, wastewater treatment, pulsed electric field sterilization, or biological tissue ablation.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A high-voltage pulse generation circuit based on a pre-boost structure, characterized in that: It includes a DC power supply, a pre-stage Sepic boost circuit, and a pulse forming module connected in sequence. Among them, the pulse forming module includes multiple cascaded Marx high-voltage pulse circuits, thus realizing the boosting of the DC power supply by the pre-stage Sepic boost circuit, transmitting the boosted electrical energy to the pulse forming module, and forming high-voltage pulses on the load by using the parallel charging pump voltage and series discharge of the Marx high-voltage pulse circuit.

2. The high-voltage pulse generation circuit based on the pre-boost structure according to claim 1, characterized in that: The pre - Sepic boost circuit includes an inductor and an inductor , a capacitor and a switching transistor . One end of the inductor is connected to the positive pole of the DC power supply . The other end is successively connected to the negative pole of the DC power supply through the capacitor and the inductor . And a switching transistor is connected between the inductor and the capacitor . The drain of the switching transistor is connected to the source of the switching transistor . The source of the switching transistor is connected between the negative pole of the DC power supply .

3. The high-voltage pulse generation circuit based on the pre-boost structure according to claim 2, wherein: The pulse forming module includes cascaded Marx high-voltage pulse circuits. The -th stage Marx high-voltage pulse circuit includes capacitors , diodes , thyristors and switching tubes , and ; Thyristor The anode of the thyristor is connected to the capacitor and the inductor therebetween. The anode of the thyristor is connected to the anode of the diode through the capacitor. The cathode of the diode is connected to the inductor and the cathode of the switching transistor therebetween. And the diodes , , , to are connected in series in the same phase in the same loop;​​​​ Switching transistor The drain of which is connected to the thyristor and the capacitor Therein, the source of the switching transistor is connected to the cathode of the diode and the diode Therein.

4. The high-voltage pulse generation circuit based on the pre-boost structure according to claim 3, characterized in that: Switching transistor is an IGBT or a MOSFET, and the switching transistor is an IGBT or a MOSFET.

5. A working method of a high-voltage pulse generation circuit based on a pre-boost structure, characterized in that: It includes an inductor charging preparation stage, a capacitor charging and voltage pumping stage, a capacitor supplementary charging stage, and a high-voltage pulse output stage that are executed cyclically; Among them, the steps of the inductive charging preparation stage are as follows: Turn on the switching transistor , and at the same time turn off the switching transistor and the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor through the switching transistor , and the capacitor charges the inductor through the switching transistor . The steps of the capacitor charging and voltage boosting stage are as follows: Turn off the switching transistor and the switching transistor , turn on the control thyristor . At this time, the diode conducts, and the DC power supply and the inductor storing energy charge the capacitor simultaneously to boost the voltage of the capacitor . Moreover, the inductor storing energy, the inductor storing energy and the DC power supply charge the capacitor simultaneously to achieve voltage boosting until the voltage of the capacitor reaches the maximum capacitor voltage . At this time, the anode current of the thyristor is lower than the holding current, and the thyristor turns off; The steps of the capacitor supplementary charging stage are as follows: turn off the switching transistor , the switching transistor and the thyristor . At this time, the diode is cut off, and the DC power supply charges the capacitor , the inductor through the inductor , further increasing the voltage of the capacitor ; The steps of the high-voltage pulse output stage are as follows: Turn on the switch tube and the switch tube , turn off the thyristor . At this time, the diode is cut off, and the DC power supply charges the inductor . The capacitor charges the inductor through the switch tube . At the same time, the capacitor discharges through the switch tube in series to the load, thus forming a high-voltage pulse on the load.

6. Application of a high-voltage pulse generation circuit based on a pre-boost structure in electrostatic precipitation, wastewater treatment, pulsed electric field sterilization, or biological tissue ablation.

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