Use of State Estimator for Grid Operations at TEPCO in Japan

The TEPCO Power Grid has updated its state estimator in March 2015. The update realized the inclusion of the 154 kV system and the more precise modeling of the neighboring system. This section describes how the 154 kV system was included in the state estimation with tapping customers. In addition, this section gives a detailed explanation on the system reduction of the neighboring system. This system reduction method makes it possible to create the power system analysis data with limited data available from the neighboring system.