The difference between auto transformer and ordinary transformer

author: MagTop
transformer is a static electrical device used to convert AC voltage and current to transmit AC power. It is based on the principle of electromagnetic induction to achieve electrical energy transfer. Transformers can be divided into power transformers, furnace transformers, rectifier transformers and other special-purpose  transformers according to their uses.
auto transformer
The difference between  auto transformer and ordinary transformer:

1. The primary side and the secondary side are not only magnetically connected, but also electrically connected, while ordinary transformers are only magnetically connected.

2. The capacity of the power supply passing through the  transformer  is composed of two parts: the electromagnetic induction power between the primary winding and the common winding, and the conduction power directly conducted by the primary winding.
auto transformer

3. Since the  auto transformer  winding is composed of primary winding and common winding, the number of turns of the primary winding and the height of the primary winding and the current of the common winding and the leakage reactance generated by the common transformer  are correspondingly reduced, and the short circuit of the auto transformer The reactance X is (1-1/k) times of the short-circuit reactance X of ordinary transformers, and k is the transformation ratio of the transformer.

4. If the  auto transformer  has a third winding, the third winding will occupy the common winding capacity, which will affect the operation mode and exchange capacity of the  auto transformer.
auto transformer

5. Since the neutral point of the  auto transformer  must be grounded, the planting setting and configuration of the relay protection are complicated.

6. The  auto transformer  is small in size, light in weight, easy to transport, and low in cost.