Trapezoidal modulation technique is a technique to
advance the control ability by using on-line computation of
PWM patterns. This is based on the classical uni-polar PWM
switching. In this method a modulating trapezoidal signal
Vm(t) with an amplitude (Ar) and the frequency (fs) is
compared with a carrier triangular signal Vtri(t) which is a
train waveform with a frequency fc and amplitude Ac. The
output frequency of the converter is decided with the
frequency of the modulating wave