For Water Turbine Generator Condition Monitoring And Intelligent Fault Diagnosis System

Hydroelectric generating sets are large apparatus, which convert hydraulic energy into electric power, and their running conditions determine whether the hydro-plant can supply electric power safely and economically. During the past century, the servicing system for the HGS which according to the planning based on statistics theory carrys out the minor repair, medium repair and heavy repair at the regular intervals has the shortcomings of superfluous or lacking repair generally. Especially with the hydroelectric generating set colossal-rization, the shortcomings are more obvious, which increase the cost of the enterprise. Therefore, the effective system of state monitoring and fault diagnose for HGS, which can improve the repair pertinency and enhance the security and reliability of HGS, have important effect to power industry and to entire national economy.Based on the analysis of characteristics of state monitoring and fault diagnosis for HGS, this dissertation emphasizes on the vibration fault mechanism, extracting ways for the vibration fault symptoms and the intelligent fault diagnosis technology. Firstly, according to the three kinds of causes, the vibration faults of HGS are divided into mechanical vibration fault, electromagnetic vibration fault and hydraulic vibration fault. This dissertation analyzes the fault mechanism, summarizes the fault symptoms and presents the solutions. Then, according to the shaft orbit's characteristic, based on the fractal geometry, fractal dimension is applied to extracting structure feature of shaft orbit, in order to realize figure quantification for on-line vibration fault diagnosis. At last, based on the intelligent fault diagnosis methods, an expert system fault diagnosis method based on fuzzy neural networks is proposed. The fuzzification for the vibration fault symptom, the fuzzy neural networks model in the fault diagnosis expert system of HGS are described in detail. The simulation results show that the intelligent integrated fault diagnosis method is reasonable and feasible.Based on the research mentioned above, a state monitoring and fault diagnosis system of HGS is developed. This system can collect data and analyse signal, monitor running state and forcast the trend, give an alarm and diagnosis for unnormal detected parameters and unwonted state, the operational instructions are given at the same time, which can avoid the blindness for servicing, reduce the the cost of the enterprise, and enhance the security and reliability of plant.