This paper aims at analyzing the power quality problem pertaining to a three-phase system feeding a non-linear load. It envisages installation of appropriate shunt passive filter to remedy the power quality problems in a cost effective manner. For this purpose, a three-phase system feeding a thyristorised converter has been first taken for study at two different power levels. These systems have been analyzed with reference to IEEE 519 standards with and without the presence of shunt passive filters. The parameters used for the passive filters such as their VAR rating and the quality factor of the inductance play a major role in deciding the effectiveness of these filters. The effect of these parameters on the performance of the passive filter has been analyzed and conclusions have been drawn for the appropriate choice of these parameters