县级自来水供水控制系统设计.docVIP

题 目: 县级自来水供水控制系统设计 院系名称： 电气工程学院 专业班级： 学生姓名： 学 号： 指导教师： 教师职称：  摘 要 随社会经济的迅速发展，人们对供水质量和供水系统可靠性的要求不断提高目前能源紧缺，利用先进的自动化技术、控制技术以及通讯技术，设计高性能、高节能、能适应不同领域的恒压供水系统成为必然趋势。 本设计由变频器、PLC及PID调节器组成控制系统，调节水泵的输出流量。电动机泵组由三台水泵并联而成，由变频器或工频电网供电，根据供水系统出口水压和流量来控制变频器电动机泵组之间的切换及速度，使系统运行在最合理的状态，保证按需供水。 本文介绍了采用PLC控制的变频调速供水系统，由PLC进行逻辑控制，由变频器进行压力调节。经过PID运算，通过PLC控制变频与工频切换，实现闭环自动调节恒压供水。 The Design of the Water Supply Control System for the County Level Abstract With the rapid development of social economy, the countys building is more and more modern and it demands the better of water supplys quality and reliability of water supply system. But energy resources are seriously lack, and most county-level water supply facilities are old. So it is inevitable tendency to design water supply system which has high function and saves on energy well, with help of advanced technique of automation, control and communication. At the same time this system can adapt different water supply fields. This design is consist of the variable frequency and speed regulation, PLC, PID control system for the control system. It controls the outcome of the pumps. The generator pumps are consist of parallel three pumps, and the power come from variable frequency and speed regulation or power grid. According to the water supply of constant pressure’s outcome water press and flux, the control system control the variable frequency and speed regulation, parallel pumps’ speed and cut over, cause the system move in the best rational situation, assure according to wants supply water. This design has many merits such as save energy. In this paper, the control principle of VVVF providing-water system is introduced, PLC is used to carry on logic control and invertered to modulate pressure．Through PID control principle. We realize Closed-loop control in VVVF Providing-water System. Keywords: Water