Real-time System-wide Inertia Estimation in Power Systems with High Wind Penetration Levels

Knowledge of on-line inertia in power systems with high and increasing levels of wind penetration is becoming more important for power system operators. In this paper, the basis of a real-time stored energy estimator is developed, which accounts for the inertia contribution from loads as well as generators in the system. By creating a simplified first order model of the system, power and frequency signals recorded are utilized to estimate real-time feeder stored energy by use of a linear least-squares estimator. The capability of the proposed estimator is investigated by application on a test system. The estimation error is analysed in respect of data resolution and feeder contributions to stored energy. Discussion on the requirements for applications within power systems and the communication configuration are also presented.