文档介绍：北方民族大学
学士学位论文
论文题目: 高层建筑物恒压供水系统组态控制设计
院(部)名称: 电气信息工程学院
学生姓名:
专业: 自动化学号:
指导教师姓名:
论文提交时间: 2011年5月10日
论文答辩时间: 2011年5月27日
学位授予时间:
北方民族大学教务处
摘要
本文介绍水泵在高层建筑恒压供水系统中的PLC和变频控制以及监控组态设计过程。系统使用压力变送器对供水水压进行连续检测,检测到的压力信号转换成电信号后送给可编程控制器(PLC)和变频器。PLC作为核心控制机构,一方面控制变频器和高峰补水泵工作,另一方面与上位机相连,实现对系统运行状态的组态监控;变频器通过其内部的PID调节运算功能,变频器和水泵构成执行机构,压力变送器作为检测和反馈机构,共同组成一个闭环控制系统。本系统采用一台变频器拖动三台水泵电机的起动切换、运行和调速。水泵机组采用循环使用的方式运行。系统设有监控上位机,上位机与PLC连接,完成对系统运行的数据采集和状态监控。
系统运行时,压力变送器能够实时检测到供水管网的水压值并反馈到PLC和变频器,变频器利用P1D控制策略实时调整水泵的运行速度(频率)、改变其流量,从而实现恒压供水。单台水泵工况的调节是通过变频器来改变电源的频率f来改变电机的转速n,从而改变水泵的流量Q来实现的。分析水泵的能耗比较图,可以看出利用变频器实现变频调速恒压供水,当水泵电机转速降低时,流量与转速成正比,功率以转速的三次方下降,与传统供水方式阀门节流控制相比,可以大幅度降低能耗,本系统节能效果明显。
关键词: 恒压供水组态监控 PLC 变频器
Abstract
In this paper, constant pressure pumps in the high-rise building water supply systems in the PLC and frequency control, and monitor the configuration design process. System uses hydraulic pressure transmitter for continuous water supply testing, to detect the pressure signal after the conversion to electrical signals to the programmable logic controller (PLC) and the inverter. PLC as a core control mechanism, on the one hand to control the peak transducer and pump up the work, on the other hand, connected with the puter, running on the system to achieve the configuration monitoring; inverter through its regulation of the internal operations of the PID function, transducer and pumps constitute the implementation of institutions, pressure transmitter testing and feedback as a body, the formation of a joint closed-loop control system. The system uses a frequency converter three drag pump motor starter switch, operation and speed. The use of recycled water pump unit run. PC system with monitor, PC and PLC connection, completion of the system of data collection and condition monitoring.
System, the pressure transmitter can be detected in real-time pressure water works and value back to the PLC and inverter, inverter P1D control strategies using real-time adjustment of pu