Correa Vasquez
Dr.-Ing. Pablo Ignacio Correa Vasquez
"Fault tolerant operation of series connected H-bridge multilevel inverters" (2006)
The operation of the H-bridge multilevel inverter under fault conditions is examined in this work. In the event of a fault, the cell with problems can be bypassed in order to continue the operation of the inverter. The voltage unbalance that results from the asymmetrical topology in some inverter configurations was compensated by modifying the modulation scheme. Two different approaches were considered: the Phase Shift-PWM (PS-PWM) strategy and the multilevel Space Phasor Modulation (SPM). Aspects such as the generation of firing pulses generation and the use of optimal sequences were also discussed. The proposed modulation schemes were confirmed by simulation and experimental results in a 5-level H-bridge multilevel inverter.