Synchrophasor-based real-time state estimation and situational awareness system for power system operation

Abstract

State estimation is a critical functionality of energy management system (EMS) to provide power system states in real-time operations. However, problems such as failure to converge, prone to failure during contingencies, and biased estimates while system is under stressed condition occur so that state estimation results may not be reliable. The unreliable results further impact downstream network and market applications, such as contingency analysis, voltage stability analysis, transient stability analysis, system alarming, and unit commitment. Thus, operators may lose the awareness of system condition in EMS. This paper proposes a fully independent and one-of-a-kind system by integrating linear state estimator into situational awareness applications based on real-time synchrophasor data. With guaranteed and accurate state estimation solution and advanced real-time data analytic and monitoring functionalities, the system is capable of assisting operators to assess and diagnose current system conditions for proactive and necessary corrective actions. The architecture, building components, and implementation of the proposed system are explored in detail. Two case studies with simulated data from the subsystems of Electric Reliability Council of Texas (ERCOT) and Los Angeles Department of Water and Power (LADWP) are presented. The test results show the effectiveness and reliability of the system, and its value for realtime power system operations.

Fully Distributed State Estimation for Power System with Information Propagation Algorithm

“…The major objectives of state estimation are monitoring the states of power systems, improving measurement accuracy, and detecting bad measurements. Currently, some state estimation methods have been applied in power systems such as weighted least square (WLS) method [4] - [7] and Kalman filter [8] - [10]. These methods have good performance in conventional centralized power systems.…”

Identifying Network Topology Using Travelling Wave Reflections of the Test Signal

“…During this time interval LSE may have a mismatch between measurement and model, which can create significant solution errors. Moreover, some breaker statuses may be reported incorrectly [9]. When topology changes are undetected or happen during the SCADA data polling, the estimation is likely to fail due to its dependence on the bus admittance matrix.…”

Successful deployment and operational experience of using linear state estimator in wide‐area monitoring and situational awareness projects

“…An on-line synchrophasor wide-area dynamics monitoring platform was presented in [5]. The application of situational awareness system for power system operations was demonstrated in [6]. However, the uncertainty of PMU data quality for production-grade applications has always been a concern [7,8] for control centre to adopt the wide-area situational awareness system in daily operations.…”