The Southern African Power Pool (SAPP) steady state security assessment using contigency analysis.

Abstract

The availability of electricity is an ongoing development of every sector of any economy. Studies have proved that many nations not only in Southern Africa but Africa as a whole are faced with power deficits and inconsistent supply and distribution of electrical power due to various reasons which include lack of sufficient generating sources, faulty equipment and unforeseen disturbances in the network. This negatively impacts both the quality of life and economic growth. A reliable power system, however, is one that is capable of withstanding a wide variety of disturbances and/or failures. This thesis assesses the severity of possible disturbances that can occur in the SAPP(Southern African Power Pool) network by carrying out a contingency ranking then verifying these results by performing a contingency analysis in DIgSILENT PowerFactory. By so doing, we are then able to affirm how reliable and secure the SAPP network is in accordance with the N-1 criteria. In this research, focus is given to two of the most critical and common failures to occur in a power system which are transmission line failure and generation unit failure. Both of which can cause alterations in the voltages of the transmission system and power flow thereby justifying why performing a contingency analysis allows one to determine which violations have been made after a disturbance occurs in the system. The result simulations reveal that the SAPP network is not secure in accordance with the N-1 criterion with the faults induced by the Harib-Kokerboom 1 transmission line and the Synchronous machine (2) generator contingencies being the most severe. Both contingencies led to voltage and thermal loading violations. This research is particularly important because it allows demonstrates some of the measures that can be put in place to mitigate the effects of unforeseen disturbances and failures that could occur in any given network.