Improved Switching Technique to Mitigate THD and Power Loss of NPC Inverters

Total harmonic distortion (THD) and power loss have a substantial impact on the power quality of multilevel inverters (MLIs). They are both directly impacted by the switching method of pulse width modulation (PWM). Nevertheless, traditional PWM methods designed for MLIs have challenges that result in high THD and power loss problems. In view of these concerns, a modified level-shifted carrier-based PWM switching technique is presented in this work. The main goal of the proposed PWM technique is to reduce power losses and THD of neutral-point-clamped (NPC) inverter. The software platforms PLECS and MATLAB/Simulink are used thoroughly to model and simulate the whole system. Moreover, an experimental test at a reduced scale is conducted to verify the results of the simulation study, validating the feasibility of the suggested PWM technique.