The roles of state estimator and security analysis in electricity markets

A fundamental attribute of successful electricity market is its ability to harmonize the requirements for secure operation of the physical system with commercial incentives which reside at the core of any competitive market environment. After two decades of deployment as part of the EMS for system operations, state estimator (SE) has become relatively well understood and accepted - even though in many control centers one may find performance reliability of the SE to be less than adequate. Modeling and model maintenance is often a leading source of difficulty. In the operation of a vertically integrated utility, the primary roles of the SE are geared towards security analysis (SA) of the transmission network. It acts as a gate-keeper for real-time security analysis. In the operation of competitive electricity markets, the roles of SE/SA for system reliability are ever more important and challenging for the RTOs. Furthermore, SE and SA are key elements in the market design that harmonizes physical security constraints with market incentives.