Comparative Analysis of the PWM and SPWM on Three-Phase Inverter through Different Loads and Frequencies

Abstract

This research paper aims to compare the total harmonic distortion (THD) of the three-phase inverters used in variable frequency drives (VFDs) and high-power applications such as HVDC power transmission and AC motor drive systems. THD causes electromechanical and thermal stresses on the system, and this study compares the results of Pulse Width Modulation (PWM) and Sinusoidal Pulse Width Modulation (SPWM) on the three-phase inverter under different loads and frequencies. The study is conducted using MATLAB/SIMULINK software and analyzes the THD of the three-phase inverter under the PWM and SPWM separately. The loads considered in this study include R, RL, RC, and RLC, while the frequencies include 10, 15, and 20 kHz. The results of the study show that SPWM produces a lower THD compared to the PWM, which indicates that the overall efficiency of the inverter is improved when the SPWM is used. This research is limited to fixed frequency and loads, and the study suggests that using the model predictive control (MPC) method may lead to even better results.