Design And Research On DC Charging Power Supply For High Power Pulse System

As an important part of the high power pulse system such as radar transmitters,electromagnetic emission devices and other equipment,the high voltage charge power supply's reliable and stable work plays a vital role to the system.In this paper,using the battery-powered high-voltage capacitor DC charging power supply as the object of study,we have designed it's main circuit,analysised it theoretically and conducted it's simulation research.For the design of the main circuit topology of the power supply,this paper selects a two-stage boost scheme.Based on the detailed analysis and comparison of various non-isolated and isolated boost circuits suitable for low voltage and high current applications,an inter-leaved double Boost converter is selected as the pre-boost circuit.Full-Bridge series resonant circuit is used as the post-boost circuit,which is the most suitable for high voltage capacitor charging,and the main circuit topology is given.The inter-leaved double Boost converter is actually composed of two basic Boost converters.In this paper,the working principle of the inter-leaved double Boost converter is analyzed in detail based on the analysis of the working principle of the basic Boost converter.Series resonant circuit is the ideal circuit for high-voltage capacitor charging with its anti-load short-circuit characteristic.In this article,the working principles of the full-bridge series resonant circuit is analyzed in detail,and the variation law of the resonant current and the charging voltage during the circuit working process is deduced.Because of the influence of the parasitic inductance and parasitic capacitance of the high voltage transformer in the actual system,the ideal series resonant circuit becomes a series-parallel resonant circuit.So the main modes of the series-parallel resonant circuit are analyzed in detail too,the regularities of the output current with the increase of the high voltage capacitor voltage during the charging process of the high voltage capacitor is deduced.A strategy of increasing the transformer ratio to reduce the charging time is proposed.Based on the small signal model of Boost circuit,a double closed-loop control system is designed for the upper and lower branches of the Boost circuit.The design method of the control system is given.In the work process of the series-parallel resonant circuit,the resonant frequency will increase and the output current will decrease with the increase of the output voltage,so a frequency control strategy using the feedback of output voltage is given,which can adjust the output current and improve the charging speed.Finally,the simulation of the whole circuit design is carried out,the simulation results verify the correctness of thetheoretical analysis and the feasibility of the circuit in real application.