Research On Online Monitoring System Of Oil-Immersed Transformer Insulation

Power transformer is one of key equipment in power system, whether it runs properly directly related to the stability of power transmission and distribution. On-line condition monitoring of transformer Insulation can find out transformer internal insulation at any time, providing repair work and maintenance plans with reliable basis, which can reduce equipment failure rates, improve equipment reliability level, save maintenance costs and play an important role in raising enterprise performance. Now on-line condition monitoring of transformer has been top research topics currently.This paper do research on the monitoring techniques about gas in oil and partial discharge, it stresses on on-line monitoring of gas and partial discharge monitoring methods and principles, and the corresponding hardware structural design, also carried out a preliminary study on the result processing of monitoring data and fault diagnosis technology, and also introduced a transformer monitoring software system structural.Chapter one presented the on-line monitoring of transformer insulation purpose and significance,introduces the development and application of transformer on-line monitoring technique at home and abroad, specially presentate the current line monitoring methods and principles, finally raises the purpose and research significance of this subject-making analysis on the generating mechanism and characteristic of main two types of oil-immersed transformer insulation fault accomplish the design of the initial monitoring device, set up system of transformer condition monitoring; Chapter two introduces the reasons of gas generation in transformer oil, and the real-time monitoring of the gas content in oil with Gas chromatography. It stresses on the research of the oil and gas separation technology, component gas separation and quantitative techniques, sensor detection, and hardware control; Chapter three do the research on the real-time monitoring of partial discharge. Illustrates the reasons of transformer, analyze the discharge characteristics of the PD. Ultrasonic technology to monitor partial discharge qualitative, and presente triangulation method of fix on the power of positioning. using pulse current method for quantitative detection. Do research on the principle of the pulse current method, and processing of interference signal; Chapter four do research on transformer insulation fault diagnosis technology and transformer oil gas monitoring data processing. Introduces the online fault diagnosis technique for the transformer insulation, which focus on threshold diagnostics, improved three-ratio method and David triangle method to analyze gas content in the oil and gained fault diagnosis, Finally, iIntroduce the support vector machine method of fault diagnosis of Principia Mathematica, and fault analysis with the sample data; Chapter five describes the soft system of on-line monitoring, analyse data communication and transmission. System is hierarchical and distributed structure, which is composed of on-site device control layer, transformer substation control layer and data center layer. Moreover it particularly analyses design principles on every layer; Chapter six summarizes design process on the system and all works, proposes improvement ideas.