Application Study On On-line Monitoring System Of Oil Chromatogram Faults Diagnosis For Three-winding Transformer

Power transformer, the key equipment for power plant, is a hinge connecting the plant and network. It reliability directly concerns secure and stable operation. With the increase of more large capacity generators, higher requirement is needed. The chromatogram analysis of oil solved gas of transformer, which can inflects various potential faults, is widely utilized. In order to detect faults timely, decrease the testing period and reach the status maintenance, on-line monitoring of transformer oil chromatogram has been developed and spread gradually.This thesis studies the application of BSZJ-III transformer oil chromatogram on-line monitoring equipment in Gansu 803 plant. Following the analysis of domestic and oversea present development, it demonstrates the importance of on-line monitoring system, discusses the principle of chromatogram analysis, the relationship between oil solved gas and fault types and methodologies of fault diagnosis, and also, analyzes the error leaded by monitoring system, its sources and correspondent interference suppression measures.Fault diagnosis is a new research project. This thesis demonstrates the principle and feasibility of fuzzy math hybrid evaluation method based on threshold diagnosis, spectrum diagnosis, Artificial neural network and expert system. Programs have been developed to testify the system's efficiency with some real cases. Combined with the geography characteristics of 803 plant, the installation, testing scheme and the correspondent measures of on-line monitoring system are developed. The system has operated successfully at 1 transformer in 803 plant.The analysis and comparison of on-line data and off-line data have indicated that on-line monitoring system inflect information sensitively and operate reliably. Moreover, it overcomes or avoids the man-made factors and more truly inflects the value of oil solved gas of transformer. When put into effect, it eliminates the labor of workers finely.In addition, this thesis discusses what on-line monitoring system do not do with well and correspondent method also are put forward.