Date Added: Dec 2011
The performance of multilevel inverter (such as switching loss and harmonics) is mainly decided by its modulation strategies. This paper focuses on a hybrid modulation strategy for asymmetric cascaded seven-level inverter. The proposed technique combines the fundamental frequency switching scheme and Variable Frequency Inverted Sine Pulse Width Modulation (VFISPWM). A detailed study of the modulation technique has been carried out through MATLAB/SIMULINK for switching losses and Total Harmonic Distortion (THD).A comparative evaluation between hybrid modulation strategy and the conventional Phase Disposition (PD) PWM method has been presented in terms of output voltage quality, power circuitry complexity, Distortion Factor (DF) and THD.