On‐line identification of power transformer short‐circuit parameters based on instantaneous phasor

Among the various faults of power transformers, winding are particularly common. It is known that short-circuit parameters can reflect condition, so on-line identification great significance for monitoring transformer health. An instantaneous phasor extraction method based on Second-Order Generalised Integrator Frequency-Locked Loop introduced, and then an algorithm proposed. In this algorithm, multi second-order generalised integrator frequency-locked loop used to extract fundamental phasors voltage current signals primary secondary sides transformer. After that, calculated from equation The effectiveness proposed has been verified with experimental results.