Fractal Based Space Vector PWM for Multilevel Inverters-A Novel Approach

A space vector pulsewidth-modulation (SVPWM) technique based on fractal approach for multilevel inverters is presented. This paper proposes a view that the space vector locations of multilevel inverters possess a fractal structure, and the properties of fractal structure together with the simplicity of fractal arithmetic are exploited to generate the SVPWM. The proposed method does not use any lookup tables for sector identification. The switching space vectors are also directly determined without using any lookup tables. The proposed scheme can be extended to an n-level inverter, and a generalized algorithm is also presented. The proposed scheme for generating SVPWM for multilevel inverters is explained for a five-level inverter, and experimental results are presented for a three-level inverter.