Abstract
Consumers of electrical power are most concerned about the cost of their electrical supply and also the level of reliability of their electrical supply. It is thus of the utmost importance for electrical utilities to supply customers within their requirements. This research focused on the reliability or security of electrical supply from utilities. This is an international concern for utilities and there are many ways of improving the reliability and security of electrical supply. One such method forms the background to this research: interconnected power pools. When a number of neighbouring utilities interconnect their transmission lines, their stability and therefore reliability of electrical supply are improved. This research focused on a particular power pool, namely the Southern African Power Pool (SAPP) – an interconnected power pool between the utilities of South Africa, Namibia, Botswana, Zimbabwe, Zambia, Mozambique, Swaziland and Lesotho.
To ensure that a power pool remains stable, there are certain electrical limitations on the interconnecting transmission lines. These power limitations are called transfer limits. Interconnected power pools are required to determine these limits to ensure that the whole interconnected network operates within its stability limits. In this way, if a disturbance were to occur on the interconnected network, the network would still remain stable and supply to customers would be ensured. Instability in a network can lead to partial or full blackouts. A blackout refers to the case of a large number of customers without electrical supply for an extended period. The socioeconomic effects of many people without electrical power for an extended period are devastating for any country or power pool.
Therefore the determination of accurate power transfer limits should be a priority of any power pool. However, gaps identified between the process of transfer limits studies as stated in international best practice compared to the process implemented by the SAPP could mean inconsistent, inaccurate results. This research addressed this problem using a case study on the SAPP transfer limits studies that are conducted in an annual workshop.
M.Ing. ( Engineering Management)