Seok-Min Kim, June-Seok Lee, and Kyo-Beum Lee, "A Novel Modulation Strategy Based on Level-Shifted PWM for Fault Tolerant Control of Cascaded Multilevel Inverters," The Transactions of the Korean Institute of Electrical Engineers, vol. 64, no. 5, pp. 718– > Paper

This paper proposes a novel level-shifted PWM (LS-PWM) strategy for fault tolerant cascaded multilevel inverter. Most proposed

fault-tolerant operation methods in many of studies are based on a phase-shifted PWM (PS-PWM) method. To apply these methods

to multilevel inverter systems using LS-PWM, two additional steps will be implemented. During the occurrence of a single-inverter-

cell fault, the carrier bands scheme is reconfigured and modulation levels of inverter cells are reassigned in this proposed fault-

tolerant operation. The proposed strategy performs balanced three-phase line-to-line voltages and line currents when a switching

device fault occurs in a cascaded multilevel inverter using LS-PWM. Simulation and experimental results are included in the paper to

verify the proposed method.