Maintenance Oriented Real-Time Condition Monitoring For Hydro-electric Generator Unit

Hydro-electric Generator Unit(HGU)is the main equipment in hydro power plants. With the development of Condition-Based Maintenance (CBM) for hydro power plants, the condition of HGU has become the most important factor for hydro power plants'maintenance. System architecture for HGU is proposed in this dissertation in order to realize the real-time condition monitoring and provide the information for fault diagnosis and optimal maintenance. Based on the analysis of the current maintenance mechanism in power plants, a more reasonable maintenance mechanism is put forward in order to improve reliability and achieve higher economic benefit. So Scheduled Maintenance must be considered to combine with predictive maintenance and others factors. Previous research work on optimal maintenance for HGU has been summarized in the dissertation. And then, the dissertation analyzes that the system to realize the real-time condition monitoring is necessary for HGU. According to the characteristics of HGU and optimal maintenance, some technologies have been used to realize real-time condition monitoring. Firstly, adopting some methods such as expert knowledge, model and simulation, accumulate of local knowledge and considering some other factors such as full-scale, feasible and economy, the dissertation confirms the state measurement. And secondly, according to the character of signal and the current automation systems in plant, the thesis discussed the approaches of the status monitoring. After considering the real-time of monitoring,the signal character and the hardware limit, the methods of monitoring and digital signal processing are all detailed. At last,the methods of status analysis are discussed. This paper is based on the three subprojects of the "Hydro Power Plant Optimal Maintenance Information System", which are cooperated with the Gezhouba Hydropower Plant of China Yangtze Power Co. Ltd. The three subprojects are "Condition Monitoring and Diagnosis System of Excitation", "Condition Monitoring and Diagnosis System of Governors"and "Condition Monitoring and Diagnosis System of Hydro-generator". A system is brought forward,which construct with the filed bus technology to realize the real-time condition monitoring. The system framework, function modules and schematic structure are all detailed. With the advantages of condition monitoring technology, a novel embedded equipment for the real-time condition monitoring for HGU are presented. The hardware and software structure are designed. And then, the portable workstations for experts are introduced. At last the system for 19# HGU of Gezhouba Hydropower Plant is investigated and the field application results are given. The field application results have demonstrated that the methods are feasible. It's very helpful for enhancing the maintenance quality and efficiency and reducing the maintenance cost. It will make great contributions to progressive realization of the CBM.