Dynamic simulation studies on electric industrial systems for designing and adjusting load shedding schemes

This paper presents the most important results obtained from several dynamic studies performed on industrial power systems, focusing on chemical and petrochemical power systems. The purpose is to determine appropriate load shedding schemes and to establish settings for the related protective schemes, such as the disconnection of transmission links by means of inverse power and underfrequency relays, which divide the system into several isolated subsystems in order to reduce severe load-generation unbalances, while acting together within the load shedding scheme of each subsystem. The simulations required were executed with a transient stability program to determine the dynamic performance of the power system during severe load-generation unbalances