Research On The Magnetic Current And Its Impact On The Differential Protection Of The Main Transformer Of Linhe Substation

The safety and stability of the power system is a guarantee to the life of people.The responsibility of the relay protection is to cut off the fa ult as soon as possible so as to restore the power supply.Transformer,a indispensable equipment,play an important role in the power system.The fault of transformer is not allowed due to the pivotal role.Firstly,the magnetizing current of transformer and its influence factors are studied based on the parameters of the transformer of Linhe substation.The simulation model of the transformer is built in Matlab/Simulink.The characteristics of the magnetizing current are given.The detail analysis to the magnetizing current is performed,which lay a solid foundation to the research in this paper.Then,the influence factors of the magnetizing current are simulated based on the Matlab/Simulink.The influence of the closing angle and the left magnetism on the magnetizing current is focused.The magnetizing current with different closing angles and left magnetism are studied.The analysis of these two scenarios is given.Finally,the basic principle of the transformer of Linhe substation is studied.the identification method to the magnetizing current is proposed,which can guarantee the reliability of the protection equipment.The simulation results demonstrate the rightness and the effectiveness of the proposed method.An improved method to identify the magnetizing current of transformer is proposed.