Design Of A Kind Of Front-end Converter For Small Satellite Power System

With the development of independent power supply system of new energy, new energy characteristics of instability, more and more combined with battery power supply system have been proposed and improved, forming a three-port structure has an input, output and bi-directional energy storage terminals. But with the human exploration of space gradually deepened, power density, life raised higher and higher requirements.In China's small satellite power system, still uses the design of basing on S3 R technology, with low power density of major defects and power switching devices work in hard switching state more, while lower energy conversion efficiency is further exacerbated by the problem of power density. Therefore, this article main research small satellite power system, the front-end converter among photovoltaic power converter and the power bus, committed to enhance the efficiency of the converter.This paper analyzes the energy management strategy and working principle of converter, compared major Boost circuit topology, and constructed the mathematical model of loss. Based on the loss model, the selection of key components of the converter are optimized. And the parameters of inverter drive circuit, DSP sampling circuit, some analog circuits and other peripheral circuits are compared; this paper has also prepared the DSP control program of Pre-converter to achieve the digital-analog control mode.Interleaved Boost converter has a simple control, low input and output ripple, It is very suitable for use in battery output circuit. Therefore, this article for this basic Topology into simple auxiliary circuit to achieve soft switching of all power devices, further reducing ripple and EMI, to meet the requirements of small satellites battery discharge. Combining the improved Topology with the S4 R streaming technology, this experiment designed pre-converter power supply system of small satellites.Finally, according to the principles of analysis and parameter design, the use of matlab and saber simulation platform to build a simulation model, the simulation results are computed out; on the basis of simulation building a rated output power of 300 W prototype, and completing experiments, which verify the theoretical analysis is correct.