變頻器plc恒壓供水的論文

1、 內(nèi)容摘要 隨著社會主義市場經(jīng)濟的發(fā)展，人們對供水質(zhì)量和供水系統(tǒng)可靠性的要求不斷提高，能源緊缺，居住環(huán)境越來越集中，使得城市供水系統(tǒng)的負荷變化很大，造成用戶管網(wǎng)壓力不穩(wěn)定。利用先進的自動化技術(shù)、控制技術(shù)以及通訊技術(shù)，設(shè)計高性能、高節(jié)能、能適應(yīng)不同領(lǐng)域的恒壓供水系統(tǒng)成為必然的趨勢。 以前供水方法存在耗能嚴(yán)重、污染水質(zhì)，設(shè)備使用壽命不長等弊端。變頻調(diào)速恒壓供水系統(tǒng)具有運行穩(wěn)定可靠，占地面積小，節(jié)電節(jié)水，自動化程度高，操作控制方便等特點，這

2、對于企業(yè)節(jié)能降耗、提高經(jīng)濟效益和保障設(shè)備安全、穩(wěn)定運行具有現(xiàn)實意義。 本設(shè)計是針對居民生活用水 / 消防用水而設(shè)計的。采用P L C 控制的變頻調(diào)速供水系統(tǒng)，由P L C 進行邏輯控制，由變頻器進行壓力調(diào)節(jié)。在經(jīng)過P I D 運算， 通過P L C 控制變頻與工頻切換，實現(xiàn)閉環(huán)自動調(diào)節(jié)恒壓供水。 根據(jù)以上控制要求，進行系統(tǒng)總體控制方案設(shè)計。首先，硬件設(shè)備選型，建立 I / O 表，S 7 - 2 0 0 系列 P L C 選型，繪制硬件

3、接線圖。其次，進行軟件設(shè)計，設(shè)計梯形圖控制程序，編寫下位機程序，并利用仿真軟件對下位機進行了仿真調(diào)試。再次，學(xué)習(xí)了 M C G S 工控組態(tài)軟件,設(shè)計了上位機監(jiān)控界面。最后，到實驗室進行了上位機和下位機的聯(lián)機調(diào)試，修改并完善了整個 P L C 恒壓供水系統(tǒng)的程序設(shè)計。 運行結(jié)果表明，該系統(tǒng)具有壓力穩(wěn)定， 結(jié)構(gòu)簡單， 工作可靠等優(yōu)點。關(guān)鍵詞： P L C ； 變頻調(diào)速； P I D 控制； 恒壓供水；M C G SAbstract Wit

4、h the rapid development of socialistic marketing economy, there is a growing demand for better quality of water supply and higher reliability of supply system. So it is an inevitable tendency to design and create an

5、energy-saving constant-pressure water supply system of excellent performance with the help of advanced techniques of automation, monitor-control system and communication. The general methods to solve the problem are the

6、 utilizations of constant-speed pump, high cistern or pressure air tank etc． The constant pressure water supply system with frequency-speed control has the features of high stability ， less floor space ， electricity an

7、d water-saving ， high automation and easy operation, which provides a practical platform to reduce enterprises consumption of energy ，and which also provides a significant method to increase the economic benefit and

8、a way to ensure the safe operation and stability of the equipments ． 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 p

9、ressure. Through PID control principle. We realize Closed-Loop control in VVVF Providing-water System. According to above control requirements, the whole system control scheme design. First, the hardware equipment select

10、ion, establish the I/O table, series s7-200 PLC selection, rendering the wiring diagram hardware. Second, the software design, design ladder diagram control procedures, write down a machine, and using the simulation soft