VARIABLE-STRUCTURE LOAD FREQUENCY CONTROLLERS FOR MULTIAREA POWER-SYSTEMS

In this paper, variable structure load frequency controllers (VSLFC) are proposed for interconnected power systems. Two designs are presented: the optimal variable structure load frequency controller (OVSLFC) and the pole placement variable structure load frequency controller (PPVSLFC). The choice of the controllers switching vectors is based on local information and accessible state variables. The effectiveness of the proposed controllers is demonstrated through their application to two-area and three-area interconnected power systems. The results reveal that there is a significant improvement in the system dynamic performance with VSLFC over that with an integral controller. Moreover, the performance of the system using the proposed controllers was found to be quite insensitive to the system parameters uncertainties.