Common mode event perspectives from the canadian electricity association equipment reliability information system

The occurrence of common mode events can be detrimental to the Bulk Electricity System and therefore it is important to record related event details for further analysis and influence design decisions to minimize the occurrence and impact of these types of events. Due to their infrequent nature, common mode events are best suited for study on a larger, aggregate system scale. This paper describes the Canadian Electricity Association (CEA) outage data and statistics presently available and the type of information that it contains that may be utilized for the analysis of common mode events in electric power systems. The detail of outage event data captured in the CEA outage database is demonstrated through a sample analysis that illustrates the various perspectives that this database can provide. This paper has been prepared to support wider efforts within the industry to identify best practices for common mode event data collection and analysis, identification of approaches for calculating historical common mode reliability indices and setting confidence intervals on future performance indices.