The Research On Non-isolated Three-port DC-DC Converter

The architecture and control mode of spacecraft power controller unit(PCU)are important factors for the performance of spacecraft power system, after manyyears of research and development, there has formed many mature architecturesfor PCU, and many of them have been applied to different satellite launches. Inrecent years, there’re more and more researches on integrated PCU, given thatsuch PCUs have advantages of integrated control, fast dynamic response, smallvolume, big power density, etc. This topic is proposed to design a kin d ofnon-isolated three-port DC-DC converter and its control scheme, to get acontroller that can realize power supply work requirements andwith goodperformance.In this paper, after researching and comparing various isolated andnon-isolated three-port DC-DC converters, finally choose a kind of non-isolatedthree-port DC-DC converter based on double-inductor Boost and two-way Buckconverter with double-inductor topology, which contains no coupling inductors.Through the analysis of the non-isolated three-port DC-DC converter’s workingconditions, determine the parameters of the main power topology; through smallsignal analysis, establishes the model of each port;based on the actual workingstatus of the satellite power, adopt a reasonable way of working and energymanagement solutions; in order to ensure the converter has high stability anddynamic response characteristics in a variety of work modes, adopt double-loopcontrol as the control method, and the design is verified by calculation ofcompensation network parameters. Through the simulation analysis, verify thefeasibility of the proposed scheme, and adjust the relevant parameters to meet thedesign requirements. Finally, through constructing the actual circuit,thefeasibility and reliability of the design is verified.The proposed non-isolated DC-DC converter of this topic verify thefeasibility of integrated power supply controller scheme, after adding maximumpower point tracking (MPPT) control mode for the control circuit, the solar arrayoutput maximum power can be realized, the entire power system’s working stateis stable and has good performance.