Edohen O.M, Ike, S.A & Okhumeode, M.E


Unbalance loading in power distribution network has continued to pose a great threat to the electricity grid system due to phase load inequality, especially where large single–phase loads are used. The network configuration and length also have effects on the voltage unbalance in the feeder. In low voltage residential feeders, majority of the houses have single–phase power supply. This research focused on finding the revenue loss on JBS 1 Estate 11/0.415kV sub-station. Using direct calculation on established formulas, the values of the unbalance voltages and current were calculated using the real time field data obtained during the period under investigation. It was observed that the highest voltage unbalance of 4.13% was recorded in the month of May while low voltage unbalance figure of 1.05% was recorded in the month of January as depicted in Table 2 and Figure 1 respectively. The research further revealed that the annual revenue loss on JBS 1 Sub-station is quite high during the period under investigation which amounted to N4,688,759.90 (four million, six hundred and eighty-eight thousand, seven hundred and fifty-nine naira, ninety kobo) which is predicted to be a high revenue loss to the utility company. Read full PDF

Keywords: Voltage Unbalanced, Revenue Loss, NERC, Unbalanced Loading, Sub-Station


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