Research On A High Voltage DC Power Supply Based On LC Serier Resonant

With the development of power electronic technology and appearance of new high performance high voltage and high frequency power electronic devices, high voltage power supply begin to widely used in military, industry, agriculture and medical treatment. Based on the features of high voltage electrostatic field in the portable electronic microscope, a kind of small power small volume and high performance high voltage power supply was designed. In this paper, a wide range regulation voltage circuit and a series resonant circuit in the light load were mainly researched on.Based on the research of the topology and control method, a kind of high voltage power supply was designed. It contains three parts: DC/DC converter, LC series resonant circuit and the multiplier circuit.In order to overcome the discontinuous inductor current, using the Buck converter in the light load,a switch was increased in the circuit and realized the inductor current continuous. Then a detailed analysis of its operating principle was introduced. At the same time, a soft switching condition was introduced. At last, the computer simulation and experimental results show that the principle of the circuit is correct.Completely different from the series resonant working in the weight load, the series resonant has its features, in the light load. Firstly, the operation of the resonant circuit was taken into analysis in detail. Then, the mathematical model was introduced and kinds of characteristic were analyzed in the light load. The conditions that inductor current can't reverse resonance after the half period were deduced. At last, the conclusions that LC series resonant circuit worked in low Q and switching frequency was slightly less than the resonant frequency has the good properties were drawn.In this paper, a double CW multiplier circuit was analyzed. Because of the phase shifting 180 degrees, the ripple of the output voltage was decreased and it also decreases the output voltage drop.Finally, a prototype was designed and the experimental results verified the validity of the theoretical analysis and the stability is 8.93×10^-5, in a period of time.