Welding power supply with improved power quality using Sheppard-Taylor converter

This paper presents a single-phase Power Factor Corrector (PFC) based on the Sheppard-Taylor topology suitable for welding applications. In order to ensure unity power factor at the input AC mains, a Pulse-Width-Modulated (PWM) control is developed. The input inductance of the proposed converter works in discontinuous current mode (DCM). Major favorable features of this converter like inherent short-circuit current limitation and fast parametrical response to load and source voltage conditions will result in better welding performance and weld quality. The performance of the entire system is evaluated on the basis of Total Harmonic Distortion (THD) of the source current, input power factor, dynamic response, voltage regulation and robustness to prove its effectiveness in terms of excellent power quality.