基于空间飞行器放电调节电路的建模与仿真

Modeling and Simulation Based on the Discharge Regulation Circuit of Spacecraft

电源分系统是空间飞行器能够稳定运行的保障系统,航天器电源包括分流、充电和放电电路。当航天器进入地影期或者弱光区时需要蓄电池放电供母线负载,放电采用的是恒压放电模式,也是典型的DC/DC功率变换电路。针对用于放电调节电路的隔离推挽变换器进行状态空间平均法建模,并对防止磁偏的峰值电流控制方式进行小信号分析,有助于设计师缩短电路的调试周期。通过仿真结果分析,运用状态空间平均法建立的模型与实际模型的稳定性、快速性以及高频抗干扰性基本相符,对于控制器参数设计有着重大的指导意义。

The power subsystem is a system for guaranteeing stable operation of spacecraft,and the spacecraft power supply includes shunt,charging and discharging circuits.When the spacecraft stays in the earth shadow period or the weak light area,the battery is required to discharge for the bus load in the constant voltage mode through a typical DC/DC power conversion circuit.In this paper,a model was established in the state space averaging method for the isolated push-pull converter of the discharge regulation circuit,and small signal analysis was made of the peak current control method for prevention of magnetic bias to help designers to shorten their circuit debugging period.Simulation results indicated that the model established in the state space averaging method had basically the same stability,rapidity and resistance against high frequency as the actual model,and had a great guiding significance for the design of controller parameters.