Do we have a single reference signal for the applied PSPWM in the enclosed paper (Reference signal = M1 of page 3 Fig. 4)? or all signals M1, M2, M3 are reference signals?
I think it is obvious that M1, M2, ...Mn are separate signals. The text also states:
The voltages vdc2 to vdcn are controlled individually
through n-1 loops. Each voltage controller gives the
modulation index of one H-bridge module. After obtaining
n modulation indices, phase-shifted SPWM (PS-SPWM)
switching scheme is applied to control the switching devices
of each H-bridge.