Study On High-Voltage Pulsed Power Supply Based On Magnetic Switch

With the development of theory and technology,the application range of pulsed power technology is increasing.The magnetic switch made of soft magnetic materials controls the flow direction of the energy in the circuit and realizes energy compression based on the principle that“The inductance drops rapidly after the saturation of magnetic core",its excellent characteristics have been widely used in pulsed power systems because of its fast switching rate,strong pressure resistance and flow resistance.In order to obtain a higher pulse amplitude and steepness,the traditional high-voltage pulsed power supply is usually composed of multistage magnetic pulse compression circuits in series,which not only increases its overall weight and volume but also limits its working frequency due to the reset problem of the magnetic cores.Therefore,how to design and build a high-voltage pulsed power supply system based on magnetic switch reasonably so that a good pulse waveform can be produced in condition of limited initial energy storage is of great practical significance to the study on pulsed power systems.According to the basic theories of magnetic pulse compression system,a high-voltage pulsed power supply based on magnetic switch is designed,the working process of the power supply circuit is analyzed and the parameters of the circuit are designed by means of theoretical calculation,software simulation and experimental verification.The specific contents of this paper are as follows.(1)The energy compression process of high-voltage pulsed power supply is expounded through the analysis of the working principle of the power supply circuit.According to the initial conditions,the parameters of the circuit are deduced and calculated,and the theoretical calculation waveforms of the voltage of each point in the circuit is obtained through the numerical simulation of MATLAB software.(2)By analyzing the influence of various technical parameters on the performance of the magnetic core,the specification and material of each magnetic core in the circuit are selected according to the design requirements.The magnetic core winding models and power supply simulation circuit are built by Saber software to output nanosecond high-voltage pulsed simulation waveforms,and the feasibility of the design is verified by comparing the simulation output waveforms and theoretical calculation waveforms.(3)The experimental system of high voltage pulse power supply based on magnetic switch is built,and its charging and discharging time is controlled by IGBT to achieve stable repetitive operation of the power supply.The voltage signals of each point in the power supply circuit is collected by Tektronix P6015A passive high voltage probe and recorded by Tektronix TDS 2024B oscilloscope.The nanosecond high voltage pulse waveforms are obtained by the experimental measurement,which prove that the power supply has good energy steepening compression effect.This design is finally applied to the experiment of underwater discharge of needle-needle electrode,and the underwater breakdown voltage waveform can be obtained.Comparing with the experiment of underwater discharge of needle-needle electrode using a mechanical switch,the result proves its superiority,which has practical reference significance for underwater pulsed discharge studies.