Abstract: For the flow control problem of complex fluid looping system, a modified fuzzy PID controller which adapts different working conditions is designed. The lumped parameter method is used to build the simulation model. The flux and temperature model of fluid looping system is built based on fluid resistance and heat exchange theory. Other important modules of the system like centrifugal pump, stepping motor valve and liquid-to-liquid heat exchanger have been emulated at the same time. On basis of this, a fuzzy PID controller with valve status signal has been designed to decrease the effect of payload changing. Four different control algorithms, including the method described in this paper, have been compared together. The simulation results indicate the modified fuzzy PID controller has the best performance. Compared with traditional PID algorithm, it has excellent adaptability of nonlinearity, such us reducing 50 % maximum overshoot and 75 % setting time when valve of payloads has been closed.

Key words: Space station, fluid loop of space utilization, fuzzy PID, flux control, simulation

摘要： 针对复杂流体回路流量控制问题，设计了一种适应多种工况的改进型模糊PID控制器。应用集总参数法，使用液阻系数和热交换分别推导了空间应用流体回路流量和温度变化模型，同时建立了回路中离心泵、步进电动阀、液液热交换器等重要组件的数学模型。以此仿真模型为基础，基于模糊控制理论设计了一种结合阀门状态信号的改进型自整定模糊PID控制器，解决下游负载变化对主路影响的问题。文中对包括改进型模糊PID在内的4种控制算法效果进行了对比。仿真结果表明，改进型自整定控制方法控制效果最好，具有良好的非线性适应性，相比传统PID减少了实验柜阀门关闭前后50 %超调量和75 %响应时间。

关键词: 空间站, 空间应用流体回路, 模糊PID, 流量控制, 系统仿真