An on-line monitoring method for winding deformation of power transformers

A novel method for on-line monitoring winding deformation of transformers is proposed. Short-circuit reactance (SCR) of transformers in service is calculated through online measurement of the voltage and current at primary side and secondary side with different loads, which could reflect the deformation of transformer windings. This method does not need zeroing in no-load and is not affected by the excitation current and variation of prime side current of distribution transformer in service. The method has been used in distribution transformers (DT) of different capacity whose inductances changed with different variations for imitating different windings deformation in DT. Simulation results verified the feasibility and effectiveness of the proposed method for on-line monitoring of windings deformation in DT.