At present, the hybrid on-load tap-changer for large-scale application utilizes the characteristics of the thyristor current zero-crossing of the power electronic device to suppress the arc generated during the switching operation, thereby improving the service life of the transformer. In this paper, the thyristor conduction current is obtained by simulating and experimentally analyzing the arc voltage formed by the floating potential of the gate contact, and the transient process of current and voltage during the turn-on and turn-off. This study provides a reference for the selection of thyristors for hybrid on-load tap-changers to improve the performance and reliability of on-load tap-changers.