Differentiate between Natural and Forced commutation

Differentiate between Natural and Forced commutation
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1 Answer

Answer :

Natural commutation
Forced commutation
Source is AC
Source is DC
External commutating componants are not required 
External commutating componants are required
SCR turns off when its forward current goes below the holding current when the AC input changes 
Conducting SCR turns off by applying a reverse voltage across it or a reverse current pulse is forced through conducting SCR
Cost of commutating circuit is less
Cost of commutating circuit is more
Used in controlled rectifiers, AC voltage controllers etc. 
Used in choppers & inverters etc
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