Minimizing total harmonic distortion (THD) and mitigating switching power loss because of high frequency switching in a solar photovoltaic (PV) fed multilevel inverter (MLI) based grid-tied system is always considered as a research challenge. The THD and power loss of MLI determine the power quality of MLI which are influenced by the pulse width modulation (PWM) method. Yet, conventional PWM techniques for multilevel inverters (MLI) encounter challenges concerning increased total harmonic distortion (THD) and power loss issues. This research endeavor introduces a novel level shifted carrier-based PWM approach to mitigate total harmonic distortion (THD) and minimize power loss in neutral point clamped (NPC) inverters. Apart from these, thermal analysis results for the proposed PWM method are provided in this work. The proposed PWM method is tested in an NPC inverter-based grid-tied PV system. The system is modeled and simulated in MATLAB/Simulink and PLECS software platforms as well as
The integration of solar photovoltaic (PV) arrays for induction motor drives (IMDs) has attained a lot of research interest due to the versatile applications of IMD including water pumping, cement industries, electric vehicles, and rolling mills etc. Multilevel inverters (MLIs) are a prominent solution for driving medium voltage induction motors (IMs) due to their superior performances over two-level voltage source inverters (VSIs). However, the power quality performance of MLI fed IMDs greatly depends on the pulse width modulation (PWM) strategy employed. Traditional PWM strategies for MLIs suffer from power quality problem such as lower order harmonics, high THD, unbalanced power loss distribution, high switching power loss, thermal instability and electromagnetic interference (EMI) problems. In this paper, a modified PWM strategy is proposed for a solar PV fed 3-level neutral point clamped (NPC) inverter driven IMD. The proposed PWM strategy introduces a new modulating signal with l
Solar photovoltaic (PV) powered water-pumping systems are proving to be a very effective in areas where the electric grid is not available. The pulse width modulation (PWM) technique, the power quality, and the torque ripple of an induction machine employed in the solar PV fed water-pumping applications have always been a concern. This paper proposes a modified reference based PWM scheme for a neutral point clamped (NPC) inverter based induction motor drive (IMD) for the solar PV fed water-pumping system. This work mainly focuses on the improvement of power quality of induction motor, converter switching loss, and torque ripple profiles of the IMD. The proposed PWM scheme utilizes ninth harmonic and trapezoidal signals to form the modulating signal, which produces balanced and symmetrical gate drive signals for the NPC inverter employed in the IMD. The generated gate drive signals reduce total harmonic distortion (THD), switching and conduction power losses, and torque ripple of the IM