Simplified multilevel space vector pulse-width modulation scheme based on two-level space vector pulse-width modulation

A novel simplified multilevel space vector pulse-width modulation (SVM) scheme is proposed based on the two-level SVM. The voltage vectors with same amplitude and phase angle are applied to the various power units of cascaded multilevel inverter (CMLI), and the refresh times of various vectors are delayed in order, thus the corresponding multilevel output voltage waveform is formatted. During every sampling period, only the on-times of main and auxiliary voltage vectors of one-stage unit are calculated based on a two-level SVM algorithm, so the computational complexity is independent on the unit-cascaded number. Then the algorithm is simplified, and the expandability is enhanced. The simulation and experimental results prove the validity and feasibility of the novel scheme.