Generalised switching scheme for a space vector pulse-width modulation-based N-level inverter with reduced switching frequency and harmonics

This study presents a generalised online switching scheme for a space vector pulse-width modulation (SVPWM)-based multilevel inverter of any voltage level. The proposed SVPWM algorithm implements a generalised three-(similar to five) and seven-segment switching scheme using the three most desired switching states and one suitable redundant state for each triangle. In addition, a novel three-segment and seven-segment switching scheme has been proposed, which eliminates extra switching commutations and hence minimises the switching frequency of the devices while reducing harmonics. The proposed modulation algorithm using the generalised expressions is implemented online. The performance of the proposed novel algorithm for N-level inverter is tested experimentally on a five-level cascaded inverter at various fundamental frequencies and the experimental results are verified with the simulation results.