基于S7-200 PLC水厂自控系统设计

摘要

Using GPRS,PLC and instrumentation,combined PID and fuzzy PID control algorithm,a reliable and practical wireless remote control system was designed and developed.The automatic control system which is S7-200 as a core component was introduced from hardware and software.Through the self-tuning PID parameters Kp,Ki,Kd,the frequency of the inverter was controlled by the fuzzy PID controller through changing the output voltage.The pneumatic valve dosing was controlled by PID algorithm.Experimental and operational results show that： constant pressure and accurate dosing are achieved,and have high stability and accuracy.%利用GPRS,PLC和仪表等,结合PID和模糊PID控制算法,设计并开发了一种可靠实用的无线远程自控系统。从硬件和软件两方面详述了以S7-200作为核心部件的自控系统。通过自整定PID参数Kp、Ki、Kd,模糊PID控制器能够通过改变输出电压来控制变频器的频率。PID算法控制气动阀加药。实验和运行结果表明：实现了恒压供水和精确加药并且具有较高的稳定性和精确度。