CANADIAN NATIONAL POWER QUALITY SURVEY - FREQUENCY OF INDUSTRIAL AND COMMERCIAL VOLTAGE SAGS

In 1991, the Canadian Electrical Association (CEA) took a proactive ap proach to power quality problems and Initiated a three-year ''Canadian National Power Quality Survey'' involving 22 utilities, This paper wi ll present the survey results of the frequency of voltage sags at indu strial and commercial sites, monitored at their utilization voltage le vels (e.g., 120 V, 347 V) and on the utility primary side of their fac ilities, and discuss the implications as to the origins of voltage sag s, The paper will also present the total number of voltage sags at a g iven site and its correlation with the number of voltage sag incidents (i.e., one or more voltage sags occurring on one or more phases withi n a short time interval) and its implications for assessing the freque ncy of disruptions due to voltage sags at industrial and commercial si tes.