Design Of Microwave Electronic Power Supply

Microwave source are widely used in many fields, such as radar system, food industry, wood processing and rubber industry, etc. The power supply possesses a lot of segments in the microwave source equipments, so the capability of the system depends a lot on the power supply's efficiency and stability. At present, switching power supply technology is used in some oversea microwave source equipments. The technology of high voltage DC switching power supply has been successfully developed in advanced countries, but is under development in China. By using power converter, the switching power supply technology transform one type electric energy to another type, which can satisfy request of various equipments, because its high efficiency and low loss can make enormous economic profits, the switching power supply technology has got a lot of recognition and has been quickly generalized. Contrast with the traditional high voltage power, the high voltage switching power for microwave source has many advantages, such as little bulk, light weight and high efficiency, etc. It is a certain trend of the technology development that the high voltage swithing power supply will replace the traditional high voltage power supply. In this paper, the switching power supply technology has been used to make the high voltage power supply. And the general process of doing the high voltage power supply is illustrated.The microwave electronic power supply requires high voltage and high power, so the two-section conversion structure, the front and the back, is adopted in the designing scheme of the power supply. In the front section, the pre-regulator, active power factor correction circuit which bases on the active power factor correction technology of switching power supply is used to obtain the 400V DC output from the 220V AC input; while in the back, a main conversion is made to gain the output voltage of 2000V DC from the input voltage of 400V DC. There are relatively perfect over-voltage and over-current protections in the output. Various noise sources and noise-restrained circuits, which have great effects on the capability of the power supply are analyzed. At last, the experimental data and results are analyzed.