ABSTRACT
The ideal transformer has no winding resistance, has infinite primary inductance, and has perfect coupling such that all flux due to the ac excitation of the primary will link with the secondary winding. The current transformer is normally used for sampling a time-varying current within a circuit. The primary purpose of using the transformer is to obtain isolation from the actual circuit where the sample is to be taken. The ideal current transformer provides a current step-down at a designated ratio for efficiency and convenience. For a practical transformer, the primary inductance is finite, and the winding has finite resistance. A current will flow in the primary circuit even when there is no load on the secondary circuit; this current is called the magnetizing current. The DC biased inductor is the most essential magnetic component in a power converter. It exists in all basic power converters and is used in input filters as well as output filters.
