基于PID的轿车空调系统设计

Car Air Conditioning System Design Based on PID Controller

轿车空调系统由鼓风机、循环风门、混合风门、蒸发器、加热器、太阳辐射、室外空气对室内空气影响、乘客热负荷、车速等部分构成,由热平衡原理及能量守恒定律建立完整的轿车空调系统数学模型。针对空调模型,设计相应的PID控制器,来调节混合风门的开度以实现轿车车室温度调节。在Matlab 2009仿真软件中,利用Simulink工具箱建立空调控制系统的仿真模型。在仿真试验中,车室温度的调节过程大约需要1 min,温度控制准确度高。由于将一些热负荷考虑到模型中,能够较好地实现对干扰信号如太阳辐射强度、系统参数如蒸发器温度等变化量进行抑制。仿真试验表明所建立的数学模型和控制器设计是正确、可行的。

Car air conditioning system is constituted by the blower, recircular door, temperature door, evaporator, heater, solar radiation, outdoor air impact, passenger heat load, speed, and other parts, the heat balance principle and energy conservation law are used to establish the complete mathematical model of car air conditioning system. Then design a PID controller for the air conditioning model adjusting the opening degree of the temperature door to achieve the automobile cabin temperature regulation. The Simulink toolbox is used to establish air-conditioning control system simulation model in simulation software Matlab 2009. In the simulation experiment, Temperature adjustment process takes about 1 minute, the control of temperature is accuracy. Due to some heat loads considered in the model, the interference signals such as solar radiation intensity and system parameters such as evaporator temperature as those variables and so on are much more reduced. Simulation results show that the mathematical model and the controller design is correct and feasible.