This question was previously asked in

DFCCIL Executive Electrical 2018 Official Paper

Option 2 : 90°

CT 1: Current Affairs (Government Policies and Schemes)

55064

10 Questions
10 Marks
10 Mins

__Concept:__

Circuit and waveform for single-phase full controlled bridge converter supplying an R-L load with continuous load current are shown below.

For the above waveform average voltage is given by

Average voltage, \({V_{avg}} = \frac{{2{V_m}}}{\pi }\cos α \)

If α = 0° then V_{avg} will be maximum

If 0° < α < 90° then Vavg will be less than the maximum Average voltage.

If α = 0° then Vavg will be Zero.

If 90° < α < 180° then Vavg will be negative value.

**So the maximum value of α should be 90° to ensure some voltage drop through the resistance.**