Transmission Expansion Planning Using Power Transfer Distribution Factor Index

Nigerian Power Sector Reform Act of 2005 was among others meant to encourage more private participants coming in to the generation of electricity; indicating desire for an expanded network to evacuate generated power. This paper presents the analysis of transmission network expansion using the existing Nigeria 30-bus grid system as a case study. The steady state situation of the system was determined using power flow equations, after which Static Var Controller (SVC) was applied to normalize voltages at those nodes experiencing voltages outside statutory limits of ± 5% and transmission line flows beyond limit capacities. Further assessment to determine critically loaded lines was done using Power Transfer Distribution Factor (PTDF) index, and this was also used to suggest possible locations of the new transmission lines that would stabilize the entire system. From the analysis additional twelve transmission lines are needed for maximum evacuation of generating powers.