Power Transformers are the most critical component of power system. This work investigates the pattern of the fault currents contain a typical signature of the nature and type of the fault for a given winding. It determines the reliability of equipment and facilities used in a power system is an essential precondition of the energy transmission security. This dissertation aims at investigating the behaviour of dynamic insulation failure in transformer under impulse excitation like standard impulse and switching impulse. Major faults like series and shunt fault in transformer are considered for analysis. In this proposed work, the fault can be diagnosed by winding current waveform of transformer, where the equivalent circuit of transformer winding model is developed by using ORCAD PSPICE software.

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Transformer Winding Standard Impulse Switching Impulse Shunt Fault And Series Fault.