Fault Detection Method for Casing Heating in Power Transformer Based on Improved SDG
In order to solve the problem of power transformer casing heating,a power transformer casing heating fault detection method based on improved signed dinected graph(SDG)is proposed.According to the change rule of directional characteristics of SDG,each node to be detected is given the same threshold variable,and the change of its variable is expressed in the form of directional symbols.Based on the directional model,it is divided into single fault and multiple faults detection.A single fault is injected into the fault through simulation to build an intuitive fault tree model,and multiple faults are given different member-ship degrees to the same node.The regions are effectively distinguished,and then the fault contrast ratio of each region is in-troduced into the function formula of membership degree to calculate the value change range and realize multiple faults detec-tion.Simulation results show that this method is more effective in detecting the heating fault of power transformer casing.
power transformerimproved SDGdirectional characteristicthreshold variablemembership degree