Sectionalizing of low-voltage overhead grids in low load density areas as the method for supply quality improvement

This paper emphasizes the needs and importance of reliability indices improvement - the reduction of outage rate and fault duration time in low-voltage (LV) overhead grids. To achieve this goal, the paper proposes the method of sectionalizing LV overhead networks, in order to reduce the average outage time. The reduction of costs, caused by penalties for undelivered energy, is also a benefit of this approach. Fuse-switch-disconnectors are proposed as sectionalizing devices. Sectionalizing of LV overhead grids has been illustrated by one realistic example, supplied by one MV/LV substation in a suburban area of Belgrade. Two sectionalizing variants have been analyzed. The optimal number and optimal locations of fuse-switch-disconnectors have been determined for both variants: the LV grid present and future configurations. Cost-benefit and sensitivity analysis have been performed, determining investment rates of return for both variants. Finally, analyzed variants have been compared with five variants of sectionalizing idealized LV grid, which had been in focus of previous study.