1、 摘摘 要要 本文介绍了 PLC 在小区变频恒压供水系统中的应用， 主要用到了 PLC 和变频 器，系统采用变频调速方式自动调节水泵电机的速度，改变了以往先启后停的方 式，系统能够自动和手动完成各个泵的启动、停止无冲击切换及故障报警，对传 统的小区供水系统进行了改造，可以有效的解决以前供水压力波动大、系统故障 率高、能源浪费严重等一系列问题，使水压平稳过渡。在小区变频恒压供水控制 系统设计中，对变频器控制节能也进行了必要的分析。论述了小区变频恒压供水 系统原理、硬件设计、软件设计、操作、参数设定和控制系统图的设计。在设计 中利用 PLC 控制变频器，采用 PID 控制器，形成以压力为闭环的控制
2、系统，从而 实现供水压力的恒定，而泵的启动和停止可以自动和手动来实现的。 关键词关键词：PLC，变频，调速，恒压供水，节能 2 Application of PLC on Constant Pressure-Providing Water System in city Abstract: The article introduces PLC (Programmable logic controller) which bases on in the area frequency conversion constant pressure water supply system applicatio
3、n, mainly uses PLC and the frequency conversion implement, the system uses the frequency conversion velocity modulation way automatic to control water pump electrical machinery the speed, after changing the way which formerly first opened stops, the system has been able to automatic and manual compl
4、eted the start which pumped one by one, stops with the non-impact cut, as well as the breakdown reported to the police, has carried on the transformation to the traditional plot water supply system, was allowed the effective solution before supplied water the fluctuation of pressure in a big way, th
5、e system failure rate high, the energy waste is serious and so on a series of questions, caused the hydraulic pressure steady transition. In the plot frequency conversion constant pressure water supply control system design, has also carried on the essential explanation to the frequency changer cont
6、rol energy conservation. System hardware by PLC, the frequency changer, the electrical machinery, the pressure transmitter and so on is composed. Detailed elaboration plot frequency conversion constant pressure water supply system principle, hardware design, software design; Operation, parameter hypothesis, control diagram design. Uses the PLC control frequency changer in the design, uses the PID controller, forms take the pressure as the closed loop control system, thus realization water sup
