PLC在供暖锅炉控制系统中的应用设计.doc

论文(设计)题目PLC在供暖锅炉控制系统中的应用
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所在院系: 机电学院
所学专业: 应用电子技术教育
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摘要
本文是基于PLC的水暖锅炉控制应用的设计,主要采用温度传感器来采集锅炉水温信号,用水位传感器来采集锅炉水位信号,用变频器来控制循环泵的转速,并把这些信号通过模数转换送给PLC(Programmable Logic Controller),与PLC内部设定的参数进行比较,以判断是否需要进行相应的操作,从而实现PLC的自动控制的目的。其中在温度控制中,根据温度传感器检测的室外温度和出回水温度差,对温度进行控制,现室内温度的恒定;在补水泵控制中,用高亮二极管和光敏三极管配对使用检测水位既准确又无污染,避免了水资源的浪费;在循环泵控制中,用两台循环泵工作,当其中一台出现故障时,报警系统发出报警信号,PLC接收到信号后另一台循环泵自动工作。该系统精度高,具有良好的人机交互功能,采用PLC控制供暖锅炉具有可靠性高,抗干扰能力强、控制系统简单易懂、维修方便等优点。
关键词:可编程控制器(PLC),传感器,变频器,报警,自动控制
APPLICATION OF PLC IN HEATING BOILER CONTROLLED SYSTEM
Abstract:The text bases controller of PLC water heating of a boiler, which mostly adopts temperature transducer to collect signal of boiler water temperature, adopts w- ater level transducer to collect signal of boiler water level, makes use of transducer c- ontrolling rotate speed of circulation pump and sends the signals to PLC ( Programm- able Logic Controller) with modulus diversion. Then, the pare with para- meter of enactment inside of PLC, in order to judge whether PLC need to put up rele- vant operation, and that realize auto-control of PLC. There are four parts in the design which make up of the boiler temperature controller, the water pump controller, the cir- culate pump controller and the dealing with trouble .In boiler temperature controller , the numerical value of temperature may randomly change according as the different s- eason .If it use in the smaller area, it can adjust at any moment according to requirem- ent .In the water pump controller, it use more lightness diode and photosensitive dyna- tron to measure water level. This method is not only precise but also cleanly and avoi- ding waste resource .In the circulate pump controller, there are two circulate pump, if one is in trouble, the alarm is light the others will be auto working when it receives th- e signal .The design adopt PLC to control, it is higher dependability and bigger conve- nience even if it also natural working in the very badly enviro