卫星MEMS热控系统的动态特性及自主控制策略

在卫星热控系统中将高效冷却技术与系统层次的智能控制策略相结合是完成航天热控任务的理想候选方案。针对一种基于微机电系统(MEMS)的微槽道换热器和微百叶窗在卫星主动热控系统中应用的方案,应用集总参数法建立了受控对象的系统动态响应模型;提出了一种引入外热流协调因子和专家智能整定比例-积分-微分(PID)控制相结合的自主温度控制策略;完成了其在纳卫星上应用效果的仿真研究。仿真结果表明:自主温度控制策略能够根据当前的控制局势及变化趋势对多个被控量进行自主协调,不但能够有效满足星载电子设备的苛刻温控要求,同时也是实现卫星高度自主飞行的关键技术之一;该温度控制策略同样适用于其他控制场合。

Satellite MEMS Thermal Control System Dynamic Characteristics and Autonomous Thermal Control Strategy

A combination of efficient cooling techniques and intelligent control strategies provides a feasible solution to a satellite thermal control system. Focusing on the application scheme of the satellite thermal control system using micro electro mechanical systems (MEMS) based micro-channel heat exchanger and micro-machined louver arrays, a dynamic response model for the controlled object is established by means of the lumped parameter method. Then an autonomous temperature control strategy is presented with the corresponding factor of the external orbital heat flux and the expert intelligent tuning proportion-integrd-differential(PID) controller. Simulation tests on a nano-satellite is performed as an instance and the results indicate that the tempera-ture control strategy can autonomously regulate several controlled variables according to the expectation of the system situations and variety tendency. This strategy can not only satisfy the demanding cooling requirements of the heat payload of internal electronics, but also has the distinguished potential of being applied to satellite autonomous flight. The temperature control strategy proposed may also be applied to other control occasions.