Power quality assessment of the Bogotá distribution network focused on voltage sag analysis

Power quality assessment of the Bogotá distribution network has been performed using four different statistical methods. Data was collected during two years by CODENSA, the largest Colombian electricity utility. The strategies have been divided as quantitative and qualitative approaches. Quantitative strategies are based on the study of probability density functions as well as the analysis of principal components (PCA). Probability density functions of voltage sag magnitudes have been used to better characterise their occurrence. PCA has been used to improve the analysis of sags based on coordination charts. On the other hand, qualitative approaches are focused on two sag related indices: the sag activity index (SAI index) and the amount of not delivered when the disturbance occurs. Those methods have been applied to assess power quality of 249 substations.