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Transformer
The transformer changes the system voltage from one level to another using two
mutually coupled coils on a magnetic core as shown in Figure6.1. The two coils
are electrically isolated—not connected by wires. The power transfer from one coil
to the other takes place via the alternating magnetic ux in the core that links both
coils. The core is made of magnetic steel that has high permeability (low reluctances)
to the magnetic ux. The magnetic steel is also known as electrical steel for its use
in electrical machines. It is basically mild steel with a few percent alloys that greatly
improves the magnetic permeability. The magnetic ...