Autotransformer

In the example the autotransformer is used to step up the 110V input to 230V, allowing equipment designed for 230V to be used with a 110V supply (as in using European electrical equipment with lower US voltages). An autotransformer is an electrical transformer with only one winding. The "auto" (Greek for "self") prefix refers to the single coil acting on itself and not to any kind of automatic mechanism. In an autotransformer, portions of the same winding act as both the primary and secondary sides of the transformer. The winding has at least three taps where electrical connections are made. Autotransformers have the advantages of often being smaller, lighter, and cheaper than typical dual-winding transformers, but have the disadvantage of not providing electrical isolation. Note that the configuration of the autotransformer in the example is by using a typical two winding transformer, so this configuration can be used to model a tapped inductor.

published 10 years ago