Mitigation of Harmonics by Filters and Appropriate Active Filter Sizing in the Heavily Polluted Low Voltage Distribution Networks

Abstract

This research studies the effect of harmonic filters on the low voltage (LV) distribution networks. With the high penetration of nonlinear loads and capacitor bank for power factor correction, the total harmonic distortion (THD) is increasaed and aggravated to be beyond the allowable limit. The higher THD pollutes the distribution networks; also, it is considered one of the main origins of the power quality deterioration. With higher THD in voltage (THDv), the sensitive loads may be damaged and the network components may be subjected to severe thermal stresses. So, at certain level of the THDv, designers must take the decision to intervene harmonics filters to reduce the previous bad effects. Passive and active filters are traditional and novel technologies respectively, both are used to suppress the THD in the level of distribution networks. In this research, the proposed algorithm provides a comparison between the two types of filters and illustrates how to determine the proper size of the active filter (AF) to retain the allowable harmonic levels. HARENA and MATLAB programs are used to simulate the proposed algorithm and the obtained results show the AF superiority on the passive filters, also, the appropriate sizing of active filter reduces its module cost