【正文】 @@@學(xué)院本科畢業(yè)設(shè)計(jì)（論文） 摘 要 I 摘 要 隨著城市經(jīng)濟(jì)的發(fā)展，城市高樓不斷的增高，城市區(qū)域不斷擴(kuò)展，城市供水開始出現(xiàn)壓力不足的問題，水是人類生活的必須品，傳統(tǒng)的供水系統(tǒng)已經(jīng)不能滿足現(xiàn)代城市的需要。需要一個新的供水系統(tǒng)，要保證城市供水的壓力恒定，滿足用戶，并且節(jié)約能耗，自動調(diào)節(jié)，便于維護(hù)。 本設(shè)計(jì)針對上述問題，通過對現(xiàn)代控制技術(shù)的研究，對不同的恒壓供水系統(tǒng)進(jìn)行比較和分析，采用變頻器結(jié)合 PLC 的控制方案，來解決恒壓供水問題。以 PLC與變頻器控制水泵電機(jī)工作，實(shí)現(xiàn)運(yùn)行可靠、節(jié)能、低噪，維護(hù)簡單，經(jīng)濟(jì)實(shí)用的恒壓供水系統(tǒng)。這個系統(tǒng)能自動控制水 泵轉(zhuǎn)速，實(shí)時讀入管網(wǎng)壓力值，與設(shè)定值比較，由 PID 控制算法得出一調(diào)節(jié)參量，控制調(diào)速泵的轉(zhuǎn)速，最終實(shí)現(xiàn)恒壓供水。 關(guān)鍵詞 變頻器 ，恒壓供水， PLC @@@學(xué)院本科畢業(yè)設(shè)計(jì)（論文） 摘 要 II ABSTRACT With the development of city economy, increased continuously city building, city expanding regional, city water supply began to appear the pressure of shortage, the water is the human life necessities, traditional water supply system has been unable to meet the needs of modern city. The need for a new water supply system, to ensure the constant pressure of city water supply, satisfy the user, and saves energy consumption, automatic adjustment, convenient maintenance. This paper in view of the above question, through the study of modern control technology, parison and analysis of different bination of constant pressure water supply system, the control scheme of PLC converter, to solve the problem of constant pressure water supply. PLC and inverter control pump motor, to achieve reliable operation, energy saving, low noise, easy maintenance, constant pressure water supply system is economical and practical. This system can automatically control the pump speed, realtime read into the pipe work pressure value, pared with the set value, controlled by the PID algorithm to obtain a control parameter, control the speed of the pump, the ultimate realization of constant pressure water supply. Keywords： Speedfrequency variable,Constant pressure water supply,PLC @@@學(xué)院本科畢業(yè)設(shè)計(jì)（論文） 摘 要 目 錄 摘 要 ............................................................... I ABSTRACT .................................................................................................................... II 1 緒論 ............................................................................................................................... 1 ................................................................................................................ 1 城市供水需求 ............................................................................................... 1 傳統(tǒng)供水系統(tǒng)的比較 ..................................................................................... 1 恒壓供水系統(tǒng)的國內(nèi) 外研究現(xiàn)狀 ............................................................................ 3 供水系統(tǒng)安全性討論 .............................................................................................. 4 本論文主要設(shè)計(jì)思想 .............................................................................................. 4 2 系統(tǒng)的理論分析及方案的確定 ................................................................................... 6 統(tǒng)的主要參數(shù) .............................................................................................. 6 .............................................................................................. 6 ....................................................................................... 9 .............................................................................. 10 系統(tǒng)的構(gòu)成 .................................................................................................. 10 工作原理 ..................................................................................................... 11 ............................................................. 12 3 變頻恒壓供水系統(tǒng)的硬件設(shè)計(jì) ................................................................................. 13 PLC ...................................................................................................................... 13 PLC 簡介 ...................................................................................................... 13 PLC 的選型 .................................................................................................. 14 PLC 擴(kuò)展模塊 EM235 ........................................................................................... 14 EM235 的簡介 ............................................................................................. 14 EM235 的技術(shù)規(guī)范 ...................................................................................... 15 EM235 的校準(zhǔn)及配置 ................................................................................... 17 EM235 的使用說明 ...................................................................................... 17 PLC 的 I/O端口分配 ............................................................................................ 18 ................................................................................................................. 19 ................................................................................................... 22 、液位變送器 ..................................................................................... 23 ....................................................................................................... 24 恒壓供水系統(tǒng)的主電路設(shè)計(jì) ......................................................................... 24 恒壓供水系統(tǒng)的控制電路設(shè)計(jì) ...................................................................... 24 恒壓供水系統(tǒng)中 PLC 外圍接線 ..................................................................... 26 @@@學(xué)院本科畢業(yè)設(shè)計(jì)（論文） 摘 要 4 變頻恒壓供水系統(tǒng)的軟件設(shè)計(jì) ................................................................................. 28 ....................................................................................................... 28 ..............................................