Technical Losses Computation of a Typical Nigerian Radial Distribution Feeder using the Forward/Backward Sweep Approach

Aggregate Technical, Commercial and Collection (ATC&C) losses in power networks occur due to technical and commercial reasons. These losses not only reduce the system efficiency, but also increase the operational costs of the power distribution companies. To effectively minimize the ATC&C losses, power utilities must first be able to quantify the technical losses (TL) arising from the current flowing through the network elements. This study employs the forward/backward sweep power flow approach to calculate the TL. In the work, a real-life 11 kV radial distribution feeder is used as a case study to evaluate the performance of the algorithm. Two loading scenarios are considered in the study and results of the algorithm, developed in MATLAB, are presented. Numerical results obtained on the case study feeder reveal that the TL is a function of the loading of the network. The feeder when loaded to 65% of capacity recorded a total power losses of 2.4096 MW, which is equivalent to 18.5% of the injected power. On the other hand, the feeder total losses increase to 7.1112 MW, equivalent to 40% of the feeder capacity, when loaded to 90% of its capacity. The two cases result in several bus voltages falling below the lower permissible limit of 0.94 p.u., which is a clear indication that the feeder under study requires a compensation.