A dc chopper is fed from a constant voltage mains the duty ratio of chopper is progressively increased while the chopper feeds an RL load. The per unit current ripple would 

(1) increase progressively 

(2) decrease progressively 

(3) decrease to a minimum value at α = 0.5 and then increase 

(4) increase to a maximum value at α = 0.5 and then decrease

1 Answer

Answer :

A dc chopper is fed from a constant voltage mains the duty ratio of chopper is progressively increased while the chopper feeds an RL load. The per unit current ripple would increase to a maximum value at α = 0.5 and then decrease

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