ENERGY QUALITY INDEX FOR MULTITERMINAL HVDC TRANSMISSION SYSTEMS AT RADIAL AND RING TOPOLOGIES

Abstract

In this paper an energy quality index that considers time-varing disturbances, as sags and voltage harmonics, in transmission systems interconnected with wind farms is presented. The disturbances have been estensively studied in distribution system which has helped to stablish the maximun permisible levels to avoid damage to the equipment conected. On transmission systems there is a growing interest in the energy quality due to the presence of distributed generation as wind farms. Although so far there is no a specific studio that indicate power quality Index for a transmission systems levels. There are several parameters which must be taken into account, such as the magnitude and frequency of a disturbance, in order to evaluate the power quality. These parameters are obtained directly by the meters developed for this purpose. By a statistical analysis of the disturbances characteristics, these are evaluated and classified into three levels (A1, A2, A3) depending on the signal quality measured at any particular section. Also it is established a Short and Long Term Index allowing a complete evaluation of the quality of the system. The proposed Index are applied to several case studies which demonstrate the performance of the index proposed here. Key Words: Multiterminal Transmission, Harmonics, Index, Power Quality, Sags, Wind Farms