Question

A semi-converter with RLE load and a freewheeling diode has discontinuous load current with firing angle α and extinction angle β. If β < π and Vm sinβ < E then

(a) the converter operates as a line commutated inverter

(b) the conduction period is absent

(c) the freewheeling period is absent

(d) none of the mentioned

The question was posed to me in unit test.

My enquiry is from Single Phase Semi-Converters-1 in section Converters of Power Electronics

Answer 1

The correct option is (c) the freewheeling period is absent

The explanation is: As the extinction angle is less than 90 degrees, the freewheeling period is absent.