Investigations of Transformer Losses due to Unbalanced Loading in a Power Distribution Network
Authors: Edohen OM, Ike SA
The power sector has continued to experience three-phase unbalanced loading condition which is a familiar problem for power sector Engineers and therefore introduces extra burden in terms of power losses causing reduction in the loading capability of distribution transformers well below their nominal ratings. This research therefore focused on investigating the transformer losses as a result of unbalanced voltage and loading current of five selected substations of 11/0.415 kV GRA feeder in Benin City, Edo State, Nigeria using the classical analytical method on established formulas, the values of the unbalance voltages and current as well as the total power loss in each of the reported substations were calculated using the real time field data obtained during the period under investigation. The results show that the highest power loss was recorded in market square substation (0.2146 kW) while Ishegie substation recorded the lowest power loss of 0.00037 kW. Airewele substation recorded a zero voltage which shows stable and balanced voltage between phases. It is observed that all the investigated substations during the period under review recorded low power losses which confirm that the substations are doing well.
Affiliations: Department of Electrical and Electronics Engineering, Faculty of Engineering, University of Benin, PMB 1154, Benin City, Nigeria.
Keywords: Voltage Imbalance, Current Imbalance, Unbalanced Loading, Sub-Station, Power Loss
Published date: 2020/12/30