Question

what is the necessity of residual magnetism in a self excited dc generator?

Answer 1

Answer:

Explanation:

1. The small amount of magnetism is present in the rotor iron.
2. This residual magnetic field of the main poles, induced an electromotive force in the stator coils, which produces initial current in the field windings.
3. Due to flow of small current in the coil, an increase in magnetic field occurs.
4. Both shunt and series generator cannot start without residual flux . But a separately exited generator can because it has a source for field excitation.
5. Best Answer Residual magnetism is one of importan properties of ferromagnetic materials.

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Answer 2

Answer:

A self-excited shunt generator has the field coils and the field rheostat shunted across the armature connection .lf there is residual magnetism left in the field iron, then spinning the armature will produce residual voltage . This residual voltage is normally enough to begin the generation process.

Explanation:

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