The relationship between tap changer gear and voltage

In principle, the Tap Changer position is to change the number of turns of the transformer winding. As the number of turns changes, the voltage on the secondary side also changes. With fewer turns, the voltage increases, while with more turns, the voltage decreases. Moreover, when adjusting the gear, the magnetic circuit and circuit will interact, affecting the leakage reactance and causing changes in the voltage distribution. Generally, the fluctuation is around ± 5%.