Cb. Jacobina et al., Digital scalar pulse-width modulation: A simple approach to introduce non-sinusoidal modulating waveforms, IEEE POW E, 16(3), 2001, pp. 351-359
The digital scaler pulse-width modulation (DSPWM) gathers the characteristi
cs of simplicity of implementation found in the regular sampling with the f
lexibility of manipulation of the switching patterns in the space vector mo
dulation (SVPWM), This paper establishes a correlation between the SVPWM an
d DSPWM techniques. It also shows how to make the DSPWM strategy equivalent
to the SVPWM technique without loosing its simplicity of implementation. B
y using such equivalence concept a microprocessor-based scheme, which uses
standard timer circuits and a simple software algorithm, is proposed to imp
lement the DSPWM technique. The introduction of the "distribution ratio" in
this technique, allows the development of a systematic approach for implem
enting of either conventional or any modified vector strategies without cha
nging the modulator scheme. This corresponds to generate any attractive non
sinusoidal modulating signals (NSMS) in the carrier-based modulation techni
ques. Furthermore, the simple digital blocks can be easily implemented as a
n specialized integrated circuit. Simulated and experimental results demons
trate the validity of the proposed methods.