Research Of High Power Repetitive Pulse Supply

Development of pulsed power technology helps promote the civil applications greatly.These newly arisen civil applications for such things as water sterilization, flue-gastreatment, bio-medical processing are also promoting the development of repetitive pulsedpower technology. The advantages of magnetic switch and high power semiconductorswitch with long life time and high operating frequency make it possible to design manyrepetitive pulsed power devices with different performance parameters. However, gasswitch which is still the most widely used pulse switch in high pulsed power possessesmany advantages, such as simple anpraunlsgeed f opro wvoelrt ategceh annodlo cguyr. rSenot,, iht’sig hhe lddpv fu/stlde ttao,ddy iin/cdstrtre,u aicstte us ttrhiel,el s ptrelaable performance, wide workingpyesti taino ni mraptoe ratanndt lriofele t iimn em oofd gearnsswitch by using the saturable delayed property of magnetic switch, which can improve theturn-on characteristics and insulation recovery characteristics. If pulse repetition frequency(PRF) and life time of gas switch are greatly improved, the usage of gas switch in repetitiveand civil pulsed power technology will be expanded, and it also has a certain practicalmeanings to development the pulsed switch technology.Based on this purpose, this thesis presents a repetitive high-power pulse supplycontaining gas switch and magnetic switch. By utilizing the series-resonant chargingtechnology, this pulse supply can realize the fast charging for input capacitor, and the pulsesupply can also realize the quick pulse compression from ms to μs by saturable transformerand magnetic switch. After quick compression, the energy stored in high voltage capacitoris transferred to the load by gas switch. This pulse supply has been successfully applied toswitch a6Ω resistive load. The current pulse flowing through the load has a rising timeabout450ns and its peak value and FWHM are580A and0.8μs, respectively. And theoperating frequency of the pulse supply can reach200Hz.In this thesis, the detailed research procedure of the pulse supply is presented. Circuit topology of the pulse supply is designed by comparing the previous topology which iswidely used. The operating principle and charge-discharge mechanism of the pulsed supplyare analyzed in detail. Suitable saturable transformer and magnetic switch are well designed.Combining the PSpice simulation platform, the key parameters of the pulsed supply areinvestigated. By studying the main factors which influence the repetitive operation of gasswitch, this thesis puts forward the concept that the turn-on characteristics and insulationrecovery characteristics of gas switch can be improved with the assist of magnetic switch.The series-resonant charging technology is an effective way to solve the fast chargingfor big capacity capacitors. In this thesis, the principle of series-resonant charging isanalyzed, and some important parameters of the series-resonant charging device arecalculated according to the working requirements of this pulse supply. Meanwhile, thedetailed design processes of high frequency transformer, resonant inductor, driving circuitsfor IGBT are listed.The experimental research and analysis are carried out deeply. PSpice simulation resultsand experimental results are compared to identify the validity of the nonlinear model formagnetic core. This thesis also gives the qualitative analysis of the power dissipationaccumulated in gas switch with and without the assist of magnetic switch. Finally, someproblems found in the experiments are discussed deeply.