plc在火电厂输煤控制系统中的应用.doc

摘 要 输煤系统是火力发电厂的一个重要组成部分，是电厂内工作环境差，劳动强度大的一个系统。有效地提高输煤系统的自动控制和管理水平是国内众多火电厂急待解决的问题。根据电厂的实际情况在输煤系统自动化改造工程中一般采用可编程逻辑控制器 (programmable logic controller，简称PLC)实现对生产设备的自动检测与控制。再配以工业电视、模拟屏等辅助系统对输煤全线进行直接监视；采用自动广播系统实现报警及生产组织；利用上位计算机实现全面管理功能，完成对现场设备状态的显示和控制，以及智能化配煤、燃煤堆取计量、各种统计报表的生成以及与工业电视系统的联网。PLC控制系统硬件设计布局合理，工作可靠，操作、维护方便，工作良好。用PLC输煤程控系统，不但实现了设备运行的自动化管理和监控，提高了系统的可靠性和安全性，而且改善了工作环境，提高了企业经济效益和工作效率。 关键词 可编程控制器PLC，输煤，火电厂 Abstract The coal-transfer system is an importance part of the thermal power plant, is a system that work environment bad and the labor strength big inside the power plant. Increases availably automatic control and management level of the coal-transfer system is a problem that legion local steam power stations need exactly to solve. According to the actual instance of the power station, adopt the programmable logic controller generally reform engineering in coal-transfer system automation, realize to the automatic examination and control of the production equipments. Go together with again with the industry television, simulated screen accessory system etc. and they can directly watch surveillance coal whole line. Adopt the auto broadcast system to realize to give an alarm and production organization. Making use of the upper computer realizing to manage the function completely, and completing to the manifestation and control of the spot equipments appearance, and intelligent coal blending, taking measure from coal-fired pile, every kind of statistical form’s burning, and connecting networks with the industry television system, broadcast system. This paper takes SIEMENS S7-200 PLC as designing the some large boiler provide warm losing the coal control electricity system. The system can work reliably with property of easy operation and maintenance. The safety locks protection control function: In the system of losing the coal electrical engineering have the strict control in moving and stopping, each other has the homologous lock interaction relation, being start