一种SAR卫星电源变换器快速响应控制策略

A Fast Response Control Strategy for Power Converter of SAR Satellite

合成孔径雷达(SAR)卫星的电源工作在脉冲模式,输出负载变化快且负载电流很大。为满足电源电压瞬态响应等关键供电指标的要求,保证输出电压保持在指标范围内,提出一种SAR卫星电源Buck变换器快速响应控制策略。该控制策略综合线性控制和非线性控制的优势,在瞬态过程中,非线性控制基于输出电压阈值检测接管母线电压控制,一旦输出电压恢复到允许的范围内,线性控制器继续进行电压调节控制,能在不增加输出滤波器的条件下提升系统的动态响应。通过仿真和试验与传统的比例积分(PI)控制策略进行对比,结果表明:文章提出的控制策略能在不增加输出电容的情况下,减小电压动态跌落并提高响应速度,提升SAR卫星电源变换器的动态性能。

The power supply of SAR(synthetic aperture radar)satellite operates in pulse mode,and the transient of load is fast and the output current is high.In order to meet the requirement of voltage dynamic response and guarantee the output voltage in the index range,a fast response control strategy for Buck converters is proposed in the paper.The proposed strategy combines the advantages of linear control and non-linear control.In the transit state,non-linear controller regu￣lates the bus voltage based on the voltage detection.When the output voltage recovers into the required range,the linear controller takes the control of bus voltage.The proposed strategy does not increase the output capacitance,and can increase the dynamic response of the converter.The proposed strategy and conventional PI control strategy are compared through simulations and experiments.The result shows that the proposed strategy reduces the voltage transit drop and increases the dynamic response speed,and improves the dynamic characteristic of the power converter of SAR satellite.