Question

A single phase half bridge voltage source inverter has an output voltage of fundamental frequency 47 Hz and frequency modulation ratio of 39. The value of the frequencies (Hz) of harmonics in output voltage present are

Answer 1

The frequencies at which voltage harmonics occur can be indicated as
$f_k=(j{m}_f\pm k)f_1$
if $j=1,k=2,4,6,...$
$k=2;f_H=(39\pm 2)\times 47$
$=1739Hz,1927Hz$
$j=2,$ $k=1,3,5$
$k=1,f_H=(39\times 2\pm 1)\times 47$
$=(78\pm 1)\times 47$
$=3619Hz,3713Hz$