Typical Default Analysis And Research Of Power Transformerbased On Field Partial Discharge Test

In Recent year,with China's rapid economic growth,the power grid construction has largely expand.As the important equipment in power system,the power transformer's security and stability is directly affects the safe and stable operation of the power grid.Through years of statistical data analysis,transformer for insulation damage accidents account for the total number of accidents around 80%.Most of them were caused by the transformer partial discharge.Therefore,it is necessary to study the test of the power transformer partial discharge.Partial discharge measurement is a common method for monitoring and diagnostics of power transformers,and can detect insulation malfunctions.Different parameters extracted from the measured partial discharge activity can be correlated to the partial discharge source.In this thesis,one mainly analyzes power transformer partial discharge test principle,pulse current method partial discharge detection technology,the substation site test method,the field safe measures.Additionally,one also analyzes the main disturbing sources,their effect on test results,graphic characteristics,and proposes methods for eliminating or reducing disturbance by studying requirements of equipment selection in field test and calculating method of relevant parameters.Based on a lot of field test data,one summarizes the partial discharge waveform characteristics,typical patterns.Interference waveform characteristics,typical pattern and the partial discharge map and substation site interference patterns are arranged,which can provide judgment experiences for substation field testing and analysis of transformer partial discharge.