Answer / iamdon

If we supply AC to rotor winding, locking between stator
field and rotor field will not be possible(rotor field will
be pulsating), so rotor will not maintain continuous
synchronism with stator and once synchronism is lost(at
inherent current zero with AC) it will not attain
synchronism later.

Answer / sunil ulange hit nidasoshi

In AC voltage Flux is Varibale.

In DC Voltage Flux is Constant

Thats why DC Excitation is Better than AC Excitation

Sunil Ulange
Project Engineer
Greenesol power Systems Ltd, bangalore.

any questions contct @ sunil_031@yahoo.com

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