Research On Protection And Internal Faults Simulation Model Of Inductive And Phase-shifting Filtering Rectifier Transformer

High energy consumption and harmonics have long been the major problems inthe electrolytic metallurgy, electrolysis chemical, subway and other industry.Inductiveand Phase-Shifting Rectifier Filtering Transformer has a better performance infiltering and reducing energy consumption that makes it has a good future inindustrial rectifier. In order to accelerate its industrialization, especially inelectrolytic metallurgy, electrolysis chemical and subway industry, an effectiveprotection proposal for the transformer is needed.This paper mainly opens out theresearch based on the principle of Inductive and Phase-Shifting Filtering RectifierTransformer, internal faults simulation model,distinguishing the magnetizing inrushcurrent and Differential Protection.Base on the wiring mode of Inductive and Phase-Shifting Filtering RectifierTransformer, this paper analyze the fundamental working principle of Phase-Shiftingfiltering and inductive filtering, proposes a mathematical model for the Inductive andPhase-Shifting Filtering Rectifier Transformer as the theoretical basis of protectiverelaying.After comparing the difference between the current method of transformersinternal fault,this paper gives a transformers internal fault model that base on the ideaof magnetic-circuit coupled,and make a2D finite element model for a116kVAInductive and Phase-Shifting Filtering Rectifier Transformer using ANSOFTMAXWELL. Expand simulation focuse on the internal faults, so as to analyze thewinding current.Analyze the principle of the magnetizing inrush current and compare the currentmethods of distinguishing the magnetizing inrush current, proposes a newmagnetizing inrush current distinguishing method using wavelet transform. We givethe wavelet analysis for the Intermittent angle of Inductive and Phase-ShiftingFiltering Rectifier Transformer when the magnetizing inrush current happens, and useMATLAB’s wavelet transform to distinguish the magnetizing inrush current with theinternal faults current, so as to provide theoretical basis to increase the reliability ofdifferential protection.According to the fault and abnormal operation conditions that RectifierTransformer may occurred,this paper give a series of protection,and,make a focus on the differential protection.Considering the Zero-sequence current’s effect ondifferential protection,this paper proposes two main wiring proposal base on thecharacteristic of Inductive and Phase-Shifting Filtering Rectifier Transformer’swiring mode. Choose an optimal one by comparing the principles and simulationanalyzed results of these two methods.