Traveling Wave Tubes, High Voltage Switching Power Supply Design And Simulation Studies

Traveling wave tube amplifier (TWTA) is widely used in many different fields ofnational economy such as RADAR, communication and navigation. In recent years,with the development of spaceborne SAR, more and more pulse TWTA is neededprogressively. The high voltage power supply is indispensable part of TWTA.Thecapability of the TWTA depends a lot on the power supply's efficiency and stability.Therefore, researching high voltage power has magnitude and realism signification forthe development of our national economy and national defence.The detailed operating principle and characteristics of phase-shifted full-bridgezero-voltage-switching converter and series resonant converter are presented in thisthesis. The small signal model of phase-shifted zero-voltage-switching full-bridgeconverter is developed with state space averaging method, then the characteristics of thetransfer functions are analyzed with MATLAB in first step, after that the method todesign closed loop feedback control circuit is presented.Based on theses results, this thesis proposes a phase-shifted series resonantconverter to realize the high voltage power supply for TWTA. The principle is analyzedfirstly, and then the hardware circuits are given. Using PSPICE and SABER software tosimulate and analyse the phase-shifted series resonant converter and phase-shiftedfull-bridge zero-voltage-switching PWM converter raise the quality of design andreduce the cost of design.Phase shifted series resonant converter is adopted to realize the 1kW TWTA highvoltage power supply. This topology simplifies circuit design. The soft switching ofMOSFETs is easy to achieved, the switching power loss can be reduced to zero.Theswitching frequency of this convener is 100 kHz, so the size and weight of theconverter become smaller.