Residential lighting influence on cast-resin distribution transformer aging rate

Abstract

Nowadays energy efficiency and its various aspects has been taken into consideration significantly. Also, non-linear loads have been increasing tragically while absence of supervision on their harmonic contents are quite obvious. These loads are extensively used in residential and commercial parts. Such a widely use of non-linear loads are in building lighting structure when Compact Fluorescent Lamps (CFL) and Light Emitting Diode (LED) lamps are replaced with incandescent and fluorescent lamps. On the other hand distribution transformers utilized in electrical distribution network are facing and challenging with these kind of loads and their harmonics, however, there is not any significant monitoring system for the transformers. This study has specifically concentrated on the distribution cast-resin transformer aging and its performance under residential lighting load. Advantages and disadvantages of CFL and LED as well as their characteristics from energy perspective are debated. Harmonic contents of incandescent, fluorescent, CFL and LED lamps are measured and discussed using power quality analyzer. Finally, distribution cast-resin transformer de-rating and its aging rate under non-sinusoidal condition initiated by lighting load is investigated and influence of each load on transformer is discussed.