High Voltage Nanosecond Pulse Denerator And Its Discharge Characteristics At Atmospheric Pressure

The study on using high voltage nanosecond pulse discharge to create low temperature plasma has been paid more attention in the field of low temperature plasma. The characteristics of low temperature plasma with low temperature and good controllability makes it has a unique advantage in material handling, polluted disposal, sterilization and disinfection. The characteristics of low temperature plasma created by high voltage nanosecond pulse discharge are uniform, stabilized and high concentrations of active particles. Most of the high voltage nanosecond pulse generator is combined with Marx Generator and pulse-forming line at present. This paper developed a high voltage nanosecond pulse generator. Fist, impulse capacitor discharge, then the pulse transformer boosts the voltage. We use a magnetic compression network to sharpening pulse front edge. There were few reports about this way.The main research contents of this paper include these following aspects:1. Proposed a project of high voltage nanosecond pulse generator. Use a high power IGBT module to control the discharge of impulse capacitor with large current. Boost the voltage by a pulse transformer. Use a magnetic compression network to sharpening pulse front edge.2. Designed a circuit to forming a low voltage and large current pulse. This circuit can output a pulse with330V and630A. Design an IGBT overvoltage protection circuit which combined with Type C and Type RCD Snubber circuit. It protects IGBT from high voltage pulse damage when the IGBT turning-off.3. Formulated a design philosophy of magnetic switch by analysis the theory of magnetic switch and magnetic multistage compression theory. Designed an experiment to measure the dynamic characteristics of magnetic material. We gained the unsaturated permeability and saturated permeability of magnetic material through this experiment. Designed a three stage magnetic compressor network. With this network, we reduced the pulse front edge from12.38μs to88.14ns. The ratio of compressor is about140.4. Used the high voltage nanosecond pulse generator to discharge in Argon gas flow at atmospheric pressure. We observed that there are several micro discharges which sustains less then10ns in single discharge. By adjust the distance of electrode and measure the time delay of discharge current, we estimated the speed of micro discharge transmit is about105m/s.