Theoretical and practical aspects of implementing a low voltage express feeder between nearby distribution transformers to reduce annual losses

Abstract

Capacity of distribution transformers is usually determined based on peak demand forecasted along a planning period. Peak demand actualizes at different seasons depending on the load characteristics of the transformers. For example, transformers at coastal towns essentially experience peak demand during summer periods. Although such transformers are loaded up to their capacities at summer seasons, their loading level reduces drastically during the off-season periods. This study addresses technical losses of such transformers and presents a solution to reduce the total transformer losses by means of implementing a low voltage express feeder (LVEF) between transformers close by. Total load of two nearby transformers is supplied by only one of the transformers through the LVEF while the other transformer is de-energized during off-season period. Depending on the criteria addressed in this study, this approach enables a decrease in the annual total loss of the system. Study includes a pilot implementation on-site.