文档介绍：摘要
传统供水系统中存在着很多的缺点,如自动化程度不高、能耗严重、可靠性低等。本系统就是针对以上问题而设计的。
整个系统由电机调速装置和PLC两大部分构成。PLC实现宏观调控,而变频器则执行微观调控,两者紧密结合,共同完成系统的变频恒压控制任务。克服了传统供水方式中自动化程度不高、能耗严重、可靠性低等缺点。
整个控制系统中通过对水泵电机进行无级调速确保水量的供需平衡,通过压力传感器从供水管中取出信号(压力信号),变送器将信号变换成模拟量,输入到PLC,由CPU定时采集信号经过A/D转化和给定值比较,经过PID调整,输出信号给变频器。变频器通过改变输出电压及频率控制水泵运转速度,从而平稳地改变供水质量,在保证压力的前提下,变流量节约供水。
关键词:可编程控制器;变频器; 变频调速; 恒压供水系统;
Abstrct
The conventional water supply system has very ings, such as the automaticity isn’t high, the sumption is serious, reliability is low and so system is designed for the problems mentioned above.
Electromator timing device and PLC make up of the enter system, the former implements macrocosmic-regulating and the latter is for microcosmic-regulating .The two bine with each other tightly and fulfill the task of frequency conversion together under the condition of constant press,which ers the meaknees of conventional pattern of water supplying,under the condition of constant press, such as the automaticity isn’t high, the sumption is serious, reliability is low and so on.
In the system, we can insure the balance between supplying and neeging to water by steeples timing water pump electromator. Press sensor takes the by signal out from flow pipe (signal of press), convertor transfoms the signal into analog voltage and imputs it to PLC. After being A/D pared with the given ralue and regulated by PID, the timing signal collected by CPU is output to transduler. The transduler control the speed of water pump by changing output voltage and frequency, accordingly improve the quality of water supplying smoothly, so that we could chang the flux and save supplied water with the press being meet.
Key words: PLC ; frequency conversion device ; variable velocity variable frequency ; constant press water supplying system;
目录
第一章绪论 1
1
2
4
6
第二章设计内容与要求 7
7
1. 系统概述 7
2. 设计内容 7
3. 主要技术参数与技术指标 8
8
8
第三章系统方案设计 10
一. 方案选择 1