Reflection of turn to turn fault on a transformer frequency response

Transformers are an extremely important element of electrical power system. Detecting minor turn-to-turn faults on the power transformer winding is a difficult problem. Understanding frequency responses in relation to winding structures was developed by using experimental and simulation efforts. In this paper, n-section ladder network model is used to calculate frequency responses of a transformer based on state space approach. Changes of transfer function are studied due to different values of fault resistance and different fault locations. Simulation results are shown that variation of transfer function resonances due to turn to turn fault occurrence is noticeable. When turn to turn fault occurs, trend of transfer function shape is changed definitely and this characteristic is helpful.