The function and classification of transformer tap changers

Transformer tap changer can change the effective turns of the transformer winding and adjust the transformer's transformation ratio without excitation or with load. It can be divided into two types based on the switch function and usage conditions:
1, Under load conditions, that is, during operation, with current and voltage conditions, the tap changer is a load tap changer.
2, Under non excitation conditions, that is, when disconnected from the power grid and not in operation, the tap changer is a non excitation (no-load) tap changer.