基于S7-200PLC控制的变频恒压供水控制系统设计毕业(论文).doc

┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ 装 ┊ ┊ ┊ ┊ ┊ 订 ┊ ┊ ┊ ┊ ┊ 线 ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ ┊ 毕业设计（论文）报告纸 共 NUMPAGES 70 页 第 PAGE 70 页 基于S7-200PLC控制的变频恒压供水控制系统设计 摘 要 近年来，随着我国国民经济的迅速发展，能源紧缺问题日益明显，因此应用变频调速技术来提高供水质量，降低能耗，在供水领域已得到越来越广泛的重视。变频恒压供水控制系统采用先进的变频调速、PLC等技术组成一闭环控制系统，用于民用建筑、生产用水，可使水泵出口压力保持恒定。恒压供水的基本控制策略是:采用可编程控制器（PLC）与变频调速装置构成控制系统，进行优化控制泵组的调速运行，并自动调整泵组的运行台数，完成供水压力的闭环控制，即根据实际设定水压自动调节水泵电机的转速和水泵的数量,自动补偿用水量的变化，以保证供水管网的压力保持在设定值,既可以满足生产供水要求，还可节约电能，使系统处于可靠工作状态，实现恒压供水。 关键字：水泵、变频器、恒压控制、PLC Abstract In recent years, with the rapid development of Chinas national economy, the energy shortage problem is becoming increasingly apparent, so the application of VVVF technology to improve water quality, reduce energy consumption, in the field of water supply has been more and more attention. Inverter control constant pressure water supply system using advanced Frequency Control, PLC and other technical components of a closed-loop control system for civil construction, production water, can maintain a constant outlet pressure pumps. Constant pressure water supply is the basic control strategy: the use of programmable logic controller (PLC) and constitutes a frequency converter control system, optimized control of the governor to run pumps, and automatically adjusts the number of running pumps to complete the water supply closed-loop control of pressure, that is, according to the actual settings automatically adjust water pressure pump motor speed and the number of pumps, automatic compensation for changes in water consumption to ensure that the pressure of the water supply network to maintain the set value, both the water supply to meet the production requirements, but also to save power, the system is in reliable working condition, to achieve constant pressure water supply. Key words: water pump ; inverter ;constant pressure control ; energy saving effects 目录 TOC \o 1-3 \h \u 变流器对低压小容量的装置常采用6脉冲变流器，而对中压大容量的装置采用多重化12脉冲以上的变流器。负载侧变流器对低压小容量装置常采用两电平的桥式逆变器，而对中压大容量的装置采用多电平逆变器。对于四象限运行的转