CHAPTER 3 MULTILEVEL INVERTER PWM SCHEMS 3.1.3.1 Carrier based PWM schemes: The carrier-based modulation schemes for multilevel inverters can be generally classified into two categories: phase-shifted PWM and level-shifted PWM. Both modulation schemes can be applied to the CHB inverters. Figure 5-1: Level-shifted PWM for a Seven-level CHB inverter (mf = 15, ma = 0.8, fm = 50 Hz and fcr = 900 Hz)
CHAPTER 3 MULTILEVEL INVERTER PWM SCHEMS 3.1.3.1 Carrier based PWM schemes: The carrier-based modulation schemes for multilevel inverters can be generally classified into two categories: phase-shifted PWM and level-shifted PWM. Both modulation schemes can be applied to the CHB inverters. Figure 5-1: Level-shifted PWM for a Seven-level CHB inverter (mf = 15, ma = 0.8, fm = 50 Hz and fcr = 900 Hz)