微小航天器单相流体回路自主热控地面实验研究

单相流体回路是解决微小航天器热控问题的一种重要手段,但是由于其内热源功率密度高、轨道热环境变化复杂,要求其具有高度自适应控制能力。为满足开展微小航天器单相流体回路自主热控研究的需要,提出了一种单相流体回路核心部件-微机械泵的PWM控制策略及实现算法,设计并搭建了其地面等效模拟实验装置,实现了该单相流体回路包括微机械泵驱动电压-压差输入输出关系、热源载荷变化及微机械泵转速变化的开环动态特性实验研究,并在此基础上完成了所提出的单相流体回路自主控制方法控制效果的地面等效模拟实验研究,达到±0.5℃以内的自主控温效果。该控制策略除了可以实现高精度自主控温以外,由于机械泵功耗基本上与热载荷成正比,还可以减少热控系统运行能耗,因而在能量供应有限的微小航天器上具有广阔应用前景。

Ground Experimental Research on Autonomous Thermal Control of Single-Phase Fluid Loop for Micro or Mini Spacecraft

Single-phase fluid loop is an important means to solve thermal control problem of micro or mini spacecraft,however,high adaptive control ability is required due to its high power density internal heat source and complex changing orbital thermal environment.To meet the need of carrying out experimental research on single-phase fluid loop autonomous thermal control for micro or mini spacecrafts,a kind of PWM control strategy and algorithm implementation on single-phase fluid loop core component-micro mechanical pump are proposed,and ground equivalent simulation experiment equipment is designed and built.Then,the experimental research an open-loop dynamic characteristics including input-output relationship testing between micro mechanical pump driving voltage and pressure difference,heat source payload change and micro mechanical pump speed change is performed for a single-phase fluid loop.On the basis of this,ground equivalent simulation experiment research on control effect of the proposed single-phase fluid loop autonomous control method is completed,and autonomous temperature control effect of ±0.5℃ is achieved.Besides achieving high accuracy autonomous temperature control effect,the control strategy can reduce thermal control system energy consumption due to its micro mechanical pump power consumption basically proportional to heat source payload,and has broad application prospects on micro or mini spacecrafts with limited energy supply.