不同工况下飞机液冷车制冷换热系统PID控制的建模与仿真

目的解决现有研究只考虑单一制冷工况,导致数学模型建立不精确,对飞机液冷车控制系统PID控制效果产生较为不利影响这一问题,提高控制系统的控制能力。方法根据飞机的保障需求和飞机液冷车的具体工况,分别建立制冷和制热两种工况下制冷换热系统的数学模型,并利用Simulink进行仿真研究。结果与单一制冷工况下所建立的数学模型相比,两种工况下所建立的数学模型其PID控制在制冷、制热工况下响应时间分别为2.1,3.1 min,短于单一制冷工况下所建立的数学模型(2.8,4.5 min)。系统误差分别为0.75%,0.51%,低于单一制冷工况(1.5%,0.71%)。结论在两种工况数学模型下的PID控制在响应速度、控制精度等方面均显示出更好的控制能力,具有良好的军事和工业应用前景。

Modeling and Simulation of PID Control for Refrigeration Heat Exchange System of Aircraft Liquid-cooling Carts in Different Working Conditions

The present studies usually just consider one working condition to build mathematical model, which makes the model inaccurate and makes the PID control of the control system have adverse control effects. To solve the problem and enhance the control ability of the system, two different mathematic models of the refrigeration heat exchange system in refrigeration and heating working conditions were built according to the needs of the aircrafts and the working condition of the aircraft liquid-cooling carts. And a simulation research was carried out based on Simulink. Compared to the mathematical model in single refrigeration working condition, the response time of the PID control in the models in the two conditions was 2.1 min and 3.1 min respectively, which was shorter than that of the PID control in the model of single refrigeration-2.8 min, 4.5 min. And the errors of the control system were 0.75%, 0.51%, which were shorter than the errors of the PID control in the model in single refrigeration-1.5%, 0.71%. The models in the two conditions have a better PID control ability in response speed, control accuracy, and have a good prospect for industrial and military applications.