Assessing the impact of unbalanced load on the technical losses in an LV distribution network: a case study of UMEME distribution transformers

Abstract

Technical losses have for a long time affected the distribution Utility companies, Unbalanced loading is seen to be a major under looked contributor to technical losses by many utility companies. In this project, the major project aim was to study the impact of unbalanced loading on the technical losses in an LV distribution network. UMEME LV distribution Transformers were used as a case study. Collection of technical loss data for various distribution feeders and consequent analysis of the collected data was done to obtain the transformer zones heavily affected by unbalanced loading in the selected specific feeders and from this analysis 5 transformer zones are selected. A load flow study of a power system LV distribution network Using DIGSILENT software was done to determine the load unbalance percentage of each Transformer. An evaluation of the Power system distribution losses was carried out to determine the unbalanced load losses in kW and their percentage contribution to the technical losses and it was found that load imbalance significantly increases the technical losses. Another load flow study was carried out while implementing solutions to study their impact on load imbalance, one of the solutions is a phase optimization tool which makes use of Genetic Algorithm. It was found that the solutions significantly reduced the unbalanced load level in the transformers and can be used as conclusive unbalanced load loss reduction strategies for the LV distribution networks