Restoration of the South African power system after a blackout incident

Abstract

Power system restoration after a blackout incident requires an integrated effort between the generation, transmission and distribution utilities. Restoration planning of the South African interconnected power system (SA IPS) primarily focuses on establishing the generation pool and transmission grid with little focus on the distribution utility requirements. These requirements are the load size for connection, power factor support, and the source voltage's effect within the interconnected power system (IPS). All the focus, as mentioned above, is essential for the distribution utility to plan for IPS restoration. The distribution utility can align with the generation and transmission expectations by understanding the operating voltage, load power factor requirements, and size of the load that may connect. The SA IPS is unique compared to utilities within Europe, the United Kingdom and North America. The challenges stem from not having firm interconnecting tie lines from neighbouring countries to support the restoration of the SA IPS. The SA IPS primarily supports the interconnecting regions. This research intends to highlight the SA IPS vulnerabilities that may cause further delays when implementing restoration initiatives. The intention is to assist with the best course of action during the system restoration stage. The simulation assessment uses a simplified case model in DIgSILENT Powerfactory for the evaluation.