FFT Analysis of Three Phase Three Level Cascaded and Modular Multilevel Converters Using Phase Shifted PWM Technique
Multilevel inverters are considered as an alternative in the field of high power and medium voltage applications.
They can synthesize the desired voltage from several levels of DC voltages. As the number of levels increases the output
waveform can be approximated to a sine wave there by reducing the Total Harmonic Distortion. This paper presents the
analysis and comparison of conventional three level Cascaded multilevel inverters and Modular Multilevel Converter
(MMC) for resistive load. The multi carrier PWM used here is the Phase Shifted PWM. By comparing the THDs the
advantages of Modular Multilevel Converter over the Cascaded multilevel inverter is confirmed. The simulations were
performed using MATLAB/SIMULINK software.
Keywords— Cascaded multilevel inverter, Modular Multilevel Converter (MMC), Phase Shifted PWM, SPWM,THD.