Question

For the following RC triggering circuit with R load and a firing angle of α, the voltage across the R load is zero for

(a) ωt = 0 to α and ωt = π to 2π+α

(b) ωt = 0 to α

(c) ωt = π to 2π+α

(d) ωt = α to 2π

The question was asked in a national level competition.

The above asked question is from Firing Circuits-3 topic in chapter Other Circuits of Power Electronics

Answer 1

Correct choice is (a) ωt = 0 to α and ωt = π to 2π+α

Best explanation: The SCR is triggered at α therefore voltage appears across the load from ωt = α to π only as in case of a half wave firing circuit the SCR is naturally commuted at π.