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A single-phase voltage controller, using one SCR in anti parallel with a diode, feeds a load R and Vs = 230 V. For a firing angel of 90° for the SCR, the PMMC voltage connected across R would read

A single-phase voltage controller, using one SCR in anti parallel with a diode, feeds a load R and Vs = 230 V. For a firing angel of 90° for the SCR, the PMMC voltage connected across R would read Correct Answer –51.8 V

As firing angle is 90, there is ideally be no conduction in the positive half. Hence, the average value will be zero. Vo = (√2 Vs)/2π x (cos90 – 1) = – 51.8 V.

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