Unified power quality index (UPQI) for continuous disturbances

Power quality indices are being developed that attempt to quantify certain aspects of service quality. There has been considerable amount of work on the characterization of individual types of power quality disturbances and corresponding indices. However, there does not exist in the literature a standard approach that allows one to quantify the overall power quality. This paper proposes a unified power quality index (UPQI) as a useful tool for ranking sites as to their overall power quality.