Annual risk assessment for overload security

This paper presents an approach to assess the cumulative risk associated wi th overload security for the purposes of midterm power system planning. The work is motivated by a need to refine bulk pow er system reliability asses sment to meet the needs of the restructured industry. There are two main co ntributions to the work. First, the assessment is performed over a year-lon g trajectory of hourly operating conditions, resulting in reliability asses sment of all expected conditions and not just a limited number of snapshots . Secondly, the assessment is quantified by a risk index comprised of summe d products of probability and consequence. This index is a good indicator o f the actual reliability level, it is decomposable, and it can be effective ly integrated into economic decision making paradigms. The work is illustra ted using the 1996 IEEE Reliability Test System.