Online transient stability evaluation of interconnected power systems using pattern recognition strategy

Using the method of pattern recognition, an online strategy has been developed for assessing the transient stability of interconnected power systems and for evaluating the security transfer limits between neighbouring systems. This strategy makes use of: an online pattern database which contains vital system data for defining the stability of the interconnected systems; an algorithm for retrieving information from the database, for online stability monitoring and assessment; and control/steering algorithms using full-scaled transient stability simulations for offline training (creating) the database and retraining (updating). The online stability monitoring and assessment aspects of the strategy may be completed in a very short time since the main bulk of computations is done offline beforehand. Using a medium-sired interconnected transmission system as a test example, it is shown how the strategy has been effective for online applications