Real-time Transient Stability Assessment Based on Centre-of-Inertia Estimation from PMU Measurements

JAIME CEPEDA; JOSÉ LUIS RUEDA TORRES; DELIA GRACIELA COLOMÉ; DIEGO ECHEVERRÍA

IET GENERATION TRANSMISSION & DISTRIBUTION

INST ENGINEERING TECHNOLOGY-IET

Año: 2014 vol. 8 p. 1363 - 1376

1751-8687

Several smart grid applications have been recently devised in order to timely perform supervisory functions along with self-healing and adaptive countermeasures based on system-wide analysis, with the ultimate goal of reducing the risks associated with potentially insecure operating conditions. Real-time transient stability assessment (TSA) belongs to this type of applications, which allows deciding and coordinating pertinent corrective control actions depending on the evolution of post-fault rotor angle deviations. This paper presents a novel approach for carrying out real-time TSA based on prediction of area-based centre-of-inertia (COI) referred rotor angles from PMU measurements. Monte Carlo-based procedures are performed to iteratively evaluate the system transient stability response, considering operational statistics related to loading condition changes and fault occurrence rates, in order to build a knowledge-data base for PMU and COI-referred-rotor-angles as well as to screen those relevant PMU signals that allows ensuring high observability of slow and fast dynamic phenomena. The data base is employed for structuring and training an intelligent COI-referred-rotor-angle regressor based on support vector machines (SVR) to be used for real-time TSA from selected PMUs. Besides, the SVR is optimally tuned by using the swarm variant of the mean-variance mapping optimization. The proposal is tested on the IEEE New England 39-bus system. Results demonstrate the feasibility of the methodology in estimating the COI-referred rotor angles, which enables alerting about real-time transient stability threats per system areas, for which a transient stability index (TSI) is also computed.