State estimation issues facing ISO/RTO organizations

ISO/RTO organizations face multiple issues related to implementation of state estimation in a real time network model environment. The overall scope of operation and breadth of coverage by an ISO/RTO exceeds that of the typical single utility or control area entity. ISO/RTOs have a need to develop very large real time system models which encompass multiple utilities and control areas, both to support operation of the transmission systems they oversee, and to properly interface with adjoining ISO/RTOs and reliability coordination entities to address system reliability maintenance on a region-wide basis. ISO/RTOs do not own the transmission systems they oversee, and are dependant on member utilities and control areas to provide the real time telemetry and outage information necessary for operation of real time state estimator. These and other factors present unique challenges in the efforts of an ISO/RTO to successfully implement state estimation and achieve viable real time power system network applications results which can be relied upon to guide system operating decisions and assure overall grid reliability.