供水厂电气及仪表控制系统设计毕业设计说明书精品剖析.doc

学 本科生毕业设计说明书（毕业论文） 题 目：村镇供水厂电气及仪表控制系统设计 学生姓名： 学 号： 1 专 业：自动化 班 级：自动化2班 指导教师： 村镇供水厂电气及仪表控制系统设计 摘 要根据的供水要求，设计了一套系统。变频恒压供水系统由变频器、压力传感器、水泵机组、等成。包含三台水泵电机，它们组成变频循环运行采用变频器实现对水泵的软启动和变频调速，压力传感器检测当前水压信号，送入与设定值比较进行PID运算，从而控制变频器的输出电压和频率，进而改变水泵的转速来改变供水量，最终保持管网压力稳定在设定值附近关键词：；；；Rural Water Supply Plant Electrical and Instrumentation Control System Design Abstract According to the requirement of the rural water supply, Design a set of electrical and instrument control of frequency conversion constant pressure water supply system. Frequency conversion constant pressure water supply control system by frequency converter, pressure sensor, pumping unit, Digital display instrument, etc. Water supply plant for dozens of villages in fangyuan 15 km outside the water supply, Water supply plant is composed of pressure and water well group, Source well group consists of three Wells. Put water Wells water injection pressure in the reservoir, Then the pump water from the reservoir through the frequency control of motor speed control for users. Reservoir contains three submersible pump motor control water level, According to the water level is different, Start the different sets of submersible pump, Power of freshman should adopt step-down startup. At the same time contains three pressurized water pump motor, They are composed of variable frequency cycle operation system, control cabinet should be able to supply pressure water supply according to user requirements, Frequency converter, is adopted to realize of pressurized water pump soft start and frequency control of motor speed, Implement as a pump of variable, power frequency switching and automatic start and stop, between the two pumps, Current hydraulic pressure sensor signal, Into the inverter compared with the set value to PID arithmetic, To control the output voltage and frequency of the inverter, Can make a big difference to the speed of water pump motor to change water supply, Eventually maintain stability o