Abstract: This paper investigates the effect of nonlinear load variation on power factor and harmonic distortion using MATLAB/Simulink. A three-phase system with a step-down transformer and a diode bridge rectifier feeding a resistive-inductive load was modelled. The inductance was varied in steps to analyse its impact on Total Harmonic Distortion (THD) and power factor (PF). FFT analysis was used to extract the harmonic spectrum, while scope blocks were used to observe voltage-current waveforms and calculate PF. Results show that increasing the inductive component of the nonlinear load significantly raises THD and reduces power factor. This highlights the importance of harmonic analysis and the role of simulation in designing power-efficient and power-quality-compliant industrial systems.

Keywords: Power Factor, Harmonics, THD, MATLAB Simulation, Nonlinear Loads.

| DOI: 10.17148/IARJSET.2025.12327