New Switching Commutation for an Electronic Tap Changer

This paper proposes the new commutation scheme to reduce the circulation current during commutation period for electronic On-load Tap Changer (OLTC). Because the bi-directional switches are used in the electronic OLTC, 4 step commutation should be applied. The proposed commutation method is also 4 steps sequence for commutation, and based on the information of the current direction and the polarity of voltage difference. Simulation results are verified the validity of the proposed method.