A Wide-Area System for Power Transmission Security Enhancement Using a Process Systems Approach

Following a series of serious power blackout incidents in 2003, policy makers in the European Union and the USA have highlighted (i) the need for improved a.c. transmission grid infrastructure and advanced control technologies to enhance stability and security in an increasingly complex operating environment, and (ii) the importance of emerging measurement-based technology towards achieving such enhanced operation. The concept of this proposal is a system for transmission security assessment using the emerging measurement technologies of high-bandwidth SCADA systems and the wide area measurement systems (WAMS) which are based on time-synchronized phasor measurement units. It will lead to better situational awareness and initiate control action for optimal operation closer to loading constraints while reducing the risks of blackouts.Very recent developments in measurement-based analyses being used in oil, gas and chemicals plants point the way towards much better signal analysis applications for the emerging measurement-based technologies in power transmission systems. The measurement-based system proposed in this project would greatly extend the basic methods that are used at present and will lead to localization and real-time diagnosis of the root causes of threats to transmission system security and actions to control the situation. It offers a more predictive, responsive and accurate approach than the transmission system models which are currently used, while the signal analysis methods now being used in experimental WAMS and high-bandwidth SCADA systems would advance from their current narrow emphasis on Fourier methods adopted from the aerospace industries. For instance the project would develop signal analysis methods for use when transient events excite system non-linearities. This will provide a much more accurate indication of the true situation during developing emergencies.This project is timely and is giving an immediate response to research needs identified in the Spring of 2006 in policy documents from the EU and US. Success in shifting the emphasis from model-based to measurement-based assessments will benefit the wider field of a.c. transmission stability and security as well as creating an a.c. transmission security enhancement system in a fit state for technology transfer. A first-rate team has been assembled for the task, namely Imperial College London (expertise in robust damping control of inter-area oscillations) and UCL (expertise in measurement-based analysis for process systems), National Grid (provision of high-bandwidth SCADA data, system specification and testing, a UK industrial viewpoint) and ABB (provision of PMU data, system development, the industrial viewpoint from continental Europe). The university researchers will do part of the work on secondment with National Grid and ABB. It is quite realistic to expect success from this team.