【作者】 刘亚奇；

【导师】 陈梅倩；

【作者基本信息】 北京交通大学 ， 工程热物理， 2010， 硕士

【摘要】 摘要：能源工业是国民经济发展的基础工业,凝汽器作为电厂的重要设备之一,发展凝汽器系统运行参数的监测,实施故障诊断,对发电机组安全经济运行具有重要意义。本文就某600MW电站N-32400-1型凝汽器系统的状态监测与故障诊断问题开展研究,主要研究成果总结如下：针对该型号凝汽器,将冷却塔和凝汽器看作一个整体,建立了凝汽器压力应达值的计算模型；通过对凝汽器主要性能指标的分析,提炼出系统的18个运行参数,利用电站机组DCS系统的采集数据,建立了单参预测、双参预测和集成神经网络预测三种BP神经网络模型,进行对比研究,实现了对运行参数的有效预测；利用单参预测模型对凝汽器真空进行了短、中、长期预测。根据凝汽器的实时数据,结合BP神经网络的参数预测结果,开发了凝汽器状态评价模块,实现对凝汽器更为全面及时的评价。利用专家系统的故障诊断方法对凝汽器系统的常见故障进行研究,通过知识库规则的提取、机制的推理以及机制的解释,开发了凝汽器的故障诊断模块,可针对不同的测点征兆,判断出故障的原因,并给出消除相应故障切实可行的措施,从而对凝汽器的正常运行起到了一定的指导作用。对600MW电站凝汽器状态监测与故障诊断系统的开发与实现是通过两个子系统来实现的,一个是利用VB调用Matrix Vb的方法开发的凝汽器诊断子系统,另一个是利用力控组态软件开发的凝汽器监测子系统。利用该系统不仅可以对凝汽器进行实时的监测与诊断,还可根据电站DCS系统的采集数据,对凝汽器进行离线的状态评价和故障诊断。本文所开发的凝汽器状态监测与故障诊断系统可对凝汽器进行全面的评价,从而提出详细的诊断结果,给出切实可行的监督指导措施,对提高凝汽器的安全性和可靠性有积极的作用。更多还原

【Abstract】 Engrgy industry is the primary industry of economic development. Condenser is one of the important equipments in the power plant, from which the energy could be saved. Its state would seriously influence the security and economy of the turbine. So, it is important to develop the condition monitoring and fault diagnosis. Condition monitoring and fault diagnosis are studied on N-32400-1 condenser.The calculation model of exhaust pressure is established. Eighteen operating parameters are epurated from the system after analyzing its main influencing factors. Three kinds of BP neural network model were established by using the historical data. A comparison among these three kinds prediction is also studied. The single parameter prediction is used for short-term, medium-term and long-term projections. According to the state of condenser, combine with the result of BP neural network prediction, a evaluation module of the condenser state is developed for realizing a more comprehensive and timely assessment of condenser.By using the expert system, a diagnosis system of the common faults of the condenser is developed through the extraction of rules’, the studying and explanning of mechanisms’. According to the different signs of the measuring points, the reasons for failure could be judged, and the feasible steps could be provided to eliminate the faults. The system could give a good guide for the conderser.The condition monitoring and fault diagnosis system for condenser of 600MW power plant is achieved through two subsystems:one is by using vb language, and the other is by using the software of force control. This system can not only realize the real-time condition monitoring and fault diagnosis for the condenser, but also can realize the offline evaluation and diagnosis.This condition monitoring and fault diagnosis system for the condenser could comprehensive analysis the condenser, then put forward detailed analysis and give practical measures. It has a positive effect for improving the security and reliability of the condenser.更多还原