卫星SAR载荷蓄电池充电器的建模分析与设计

Modeling Analysis and Design of Battery Chargers for Micro-nano SAR Satellites

随着现代商业卫星的发展,低成本、重量轻、多功能、高集成的微纳合成孔径雷达(SAR)卫星迎来加速发展的阶段。由于SAR载荷工作时间短、峰值功率大的特点,需专门为SAR载荷配置一组高压载荷蓄电池,在相同电流下,可输出更大功率。针对高压载荷蓄电池恒流恒压充电的需求,提出采用推挽变换器的隔离升压充电器方案,搭建了推挽变换器的小信号模型,采用峰值电流控制的双环控制策略实现恒流恒压充电控制,最后在充电器样机上进行了实验验证。实验结果验证了分析的正确性与设计的有效性,可以满足SAR载荷蓄电池充电的要求。

With the development of modern commercial satellites,the micro-nano synthetic aperture radar(SAR)satellites with low-cost,light-weight,multi-functional,and highly-integrated features is entering a stage of accelerated development. Owing to the characteristics of short working time and high peak power,SAR loads should be specially configured with a set of high-voltage load batteries so as to provide higher power under the same current. In view of the demand for constant current and constant voltage charging of high-voltage load batteries,in this paper,an isolated boost converter with a push-pull topology is proposed,and an alternating-current(AC)small signal equivalent model for the converter is built. The dual-loop control strategy with the peak current control method is adopted to achieve constant current and constant voltage charging performance. Finally,experiments are carried out to validate the charger prototype. The results show that the charger meets the requirements of SAR load battery charging,which verifies the correctness of the analysis and the validity of the design.