QUALITATIVE ANALYSIS OF LOAD LOSSES ON NIGERIAN 330 kV TRANSMISSION LINES

This work aimed at providing a qualitative analysis of technical losses in transmission lines using Nigerian 330 kV lines as a case study. The specific objectives of this study include mathematical modeling of the Nigeria transmission network, incorporating long transmission lines effects on a 52-bus network. The system is modeled in DIgSILENT PowerFactory and advanced Newton-Raphson's load flow algorithm is employed to determine systems parameters of each of the 330 kV buses, hence, qualifying the evaluation of voltage profile, voltage drop, and transmission line losses. This analysis reveals variations in power generation at different locations, contributing to increased line power losses and significant voltage drops in certain bus bars. The frailest buses are identified in the northern part of the country, in areas such as Kano, Yola, Damaturu, Maiduguri, and Gombe, with voltage deviations exceeding the ±5 % of the nominal voltage level, while the strongest bus exists in the west - Egbin and Olorunsogo. The total power loss is found to correlate with the percentage line loading, with the heaviest loaded line experiencing the highest total loss such as, the Egbin-Benin line with a loading of 103.81 % experiences the highest total loss of 51.70 MW. The least efficient line in terms of power loss is Alaoji-Terminal II, which loses 34.62 % of the transmitted power. This inefficiency can be attributed to its operating conditions as it connects both the south-eastern and south-southern zones of the network but has variable power supply from both Afam, Alaoji GENCOs and Onitsha TCN.