Excitation-vibration harmonic response research of transformer in DC biasing operation

Aiming at the problem of transformer vibration in DC biasing operation, the relationship between excitation characteristics and vibration is studied. The electromagnetic coupling state equation of transformer in DC biasing operation is established. Then, the dynamic inductance and time-domain current are calculated based on the energy disturbance principle. On this basis, the identification method of exciting current is studied to present the excitation saturation state. The excitation-vibration harmonic response model is constructed to analyse the relationship between the variation law of exciting current and vibration characteristics of the core under different DC levels. The correctness of this method is verified by the comparison between simulation and experimentation.