Performance Evaluation of ISO-NE's Hybrid State Estimation

As a fundamental component of modern energy management system, State Estimator (SE) runs periodically to provide an accurate, fast and reliable estimation of the system's real-time condition, laying the foundation for subsequent network analyses and energy market operations. Traditionally, the SE input data comes from the Supervisory Control and Data Acquisition (SCADA) system. With the development of the synchrophasor technology, utility companies have increased interest in integrating PMU measurements with existing state estimation to pursue an SE performance improvement in terms of robustness, accuracy, convergence and reliability. This paper presents the work done by ISO New England (ISO-NE) to evaluate the performance of hybrid state estimation with phasor measurements introduced. The results demonstrated that the use of PMU measurements can lead to a more accurate and robust SE on modern Energy Management Systems (EMS). Particularly, the benefits of hybrid SE is more noticeable when there is a loss of SCADA.