Research And Design Of High-Voltage Switching Power Supply For Airborne Traveling Wave Tube

In order to satisfy the demands of the military field and the aerospace field, a kind of high density integrated electronic power conditioner(EPC) with miniaturized property and high efficiency which is applied to Microwave power module(MPM) has been studied widely. Some active exploratory researches were done based on this background.Several topologies commonly used in switching power supply in domestic and overseas together with the application of the soft switching technology are discussed comprehensively. The following scheme is established based on the analysis of the operating principle of the converter.The phase-shifted zero-voltage-switching PWM full bridge converter with auxiliary circuits is applied to the circuit. The high frequency voltage transformation together with the voltage multiplying rectifying is introduced due to the boosting design demand with high transformation ratio in this thesis. The UC3875 of the voltage-mode control configuration integrated circuits allowing constant frequency pulse-width modulation is emphasized in the control circuit which is configured by proportional-integral is intended to stabilize the output voltage and limit the load current. In order for the electrical isolation between PWM drive signal and drive circuit for the switch, the pulse transformer is introduced. The functions of the protective circuit are as follows: overcurrent protection, input overvoltage protection, input undervoltage protection, output overvoltage protection, output undervoltage protection and alarm. Transfer function of the closed loop control system is calculated, and the simulation of the system characteristics is done by the MATLAB to rectify the theory reliability which is useful in developing the converter to optimize the closed loop system design.Finally, the prototype of the converter is achieved via assembling and debugging on the basis of the previous parametric value. The simulation and experimental results verify the validity of the above analysis and design. Meanwhile some main experimental waveforms were obtained by implementing the major performance measurement. The theoretical analysis and project design can be verified by the experimental results.The high frequency voltage transformation together with the voltage multiplying rectifying and the soft switching technology is adopted in the scheme. It can serve as a reference for the design of high density integrated power converter with small volume, light weight and high efficiency. In addition, the design experience can be a reference for the design of low input and high output power supply.