Electric Locomotive Passing Articulated Phase Insulator High Voltage Potential Transformer Ferroresonance Analysis

The high voltage transformer is an important electrical equipment of electric locomotive, for the safe and reliable operation of locomotive plays a vital role. But Electric locomotive passing the articulated phase insulator, often appear the ferroresonance overvoltage, caused the roof protection gap discharge, transformer burned, seriously affect the safe operation of electrified railway. There is an urgent need for electric locomotive through study of articulated neutral vehicle high voltage transformer ferroresonance.This paper introduces the current research situation, characteristic, harm of ferroresonance, the structure of articulated phase insulator and way of locomotive passing neutral section. Analysis of the process of locomotive passing articulated phase insulator, to obtained the equivalent circuit model and the mathematical expression of locomotive passing neutral section, and Analysis of the causes of the electric locomotive passing the articulated phase insulator voltage transformer ferroresonance. The resistance and inductance parameters of traction transformer, contact network Supply arm, the articulated phase insulator line, and pantograph and roof high wire capacitance to ground and other parameters were calculated.The use of Matlab simulation software emulate electric locomotive passing articulated phase insulator voltage transformer ferroresonance, obtained simulation waveform, and analysis this waveform. This paper mainly studies that the effect of voltage transformer core loss for ferromagnetic resonance, and get the transformer core loss has inhibitory effect on Ferroresonance. According to the two kinds of methods to inhibit ferroresonance:One is changing the parameters of the system capacitance and inductance, to make the system away from the resonance region, which is not easy to stimulate the ferromagnetic resonance. Another approach is to consume resonance energy, destroying the resonance condition, to damp or eliminate resonance, put forward some suppression transformer ferroresonance measure, In order to improve the reliability of system operation.