基于PLC的水塔水em控制系统设计.doc

毕业论文（设计） 基于PLC的供水系统设计 系 部 自动控制工程系 专 业 名 称 电气自动化技术 班 级 姓 名 学 号 2011年月27日 The design of water supply system based on PLC Abstract With the rapid development of social economy, people water quality and water supply to demand for improved system reliability: coupled with the current energy shortage, the use of advanced automation technology, control technology and communication technology, design high-performance, engage in energy conservation, to adapt Water Supply System in different fields has become an inevitable trend.  This design is designed for the living water. By the PLC, inverter, pressure sensors, control system components, adjusting the pump output flow. Motor pumps made by the four pumps in parallel, by the frequency converter or power supply, water supply systems under the pressure and flow to control the export drive and switching speed of the motor pumps, the system is running in the most reasonable state to ensure on-demand water supply.  The design introduced with PLC control frequency control water supply system, the PLC logic control, the inverter for pressure regulation and then after PID operation, through the PLC control frequency in the frequency switching, automatically adjust the constant pressure to achieve closed-loop variable water supply. Keywords: variable frequency and speed regulation; water supply of constant pressure; PID control system; Programmable Logic Controller; Transducer目录 1绪 论 1 2恒压供水系统方案 2 2.1 本设计的内容 2 2.1.1 恒压供水系统的选型 2 2.1.2 变频调速恒压供水系统的优点 2 2.2 系统控制方案的确定 3 2.3 系统控制方案及系统特点 4 3系统硬件选型 5 3.1 PLC的选择 5 3.1.1 PLC的概述 5 3.1.2 PLC的选型 5 3.2 变频器的选型 5 3.3 水量计算及水泵的选型 6 3.3.1 用水量计算 6 3.3.2 水泵的选型 6 3.4 压力传感器的选型 7 4硬件接线图 8 4.1 PLC及变频器控制电路 8 4.1.1供水系统主电路 8 4.1.2系统控制电路 8 4.1.3 PLC接线 9 4.1.4 PLC输入输出分配 10 4.1.5 变频器接线 11 5系统程序设计 12 5.1系统工作过程分析 12 5.1.1手动运行 12 5.1.2自动运行 12 5.1.3安全问题 12 5.1.4工作泵组管理 13 5.2 PID控制及其控制算法 14 5.3程序调试 15 总 结 19 致 谢 20 参考文献 21 附 录 22 1绪 论 长期以来区域的供