基于PLC的PID控制恒压供水系统

传统的单片机控制供水系统,硬件设计和程序编制难度大,而且因工艺、电磁干扰等原因系统可靠性差,供水压力不稳定。以某生活小区泵站供水系统为对象,在充分分析PLC内置PID运算功能的基础上,考虑供水系统的特点,提出了用PLC控制变频调速恒压供水系统。该系统由PLC、变频器、水泵电机组、压力传感器及电气控制柜组成。系统的逻辑控制和PID运算由PLC完成,供水压力由PLC的模拟电位器设定。系统投入运行后,系统维护量少、供水压力稳定,有较大的推广应用价值。

PID Controlled Constant Pressure Water Supply System Based on PLC

The hardware design and programming of traditional water supply system with SCM are difficult,and factors of technics and disturbance lead to poor reliability and stability.Taking the water supply system of pumping station in certain residential area as example,constant pressure water supply system of adjustable-speed frequency conversion based on PLC is proposed by analyzing PID function inside PLC and considering the characteristics of water supply system.This system consists of PLC,frequency converter,pump motor groups,pressure sensor and electric control cabinet.The logic control and PID operation are achieved by PLC and the pressure of water supply is set by simulation potentiometer.The application results show less maintenance,stable pressure and remarkable extending value.