Assessment of transmission line common mode, station originated and fault types forced outage rates

The frequency and duration of the various types of transmission line outages has a significant impact on the operation and reliability of industrial and commercial power systems. Knowledge of the statistical characteristics of transmission line outages (e.g., types of faults: three phase, line to ground, etc.) directly affects the protection and coordination practices at these facilities. Reliability modeling of industrial and commercial power systems is dependent upon transmission line outage characteristics (e.g., terminal-related and line-related sustained outages). Generalizations of transmission line characteristics for all voltage classes can be incorrect and extremely problematic in many cases. This paper presents the some of the results of a 10 year study of the Mid-Continent Area Power Pool (MAPP) transmission line outage data statistics for 230 kV, 345 kV and 500 kV lines. This data can be used for modeling the reliability of industrial and commercial facilities being serviced by transmission lines and reveals some of the common beliefs and misconceptions about transmission line characteristics.