Robust Control System Networks

Robust Control System Networks

Robust Control in Power Systems

Robust Control in Power Systems deals with the applications of new techniques in linear system theory to control low frequency oscillations in power systems. The book specifically focuses on the analysis and damping of inter-area oscillations in the systems which are in the range of 0.2-1 Hz. The damping control action is injected through high power electronic devices known as flexible AC transmission system (FACTS) controllers. Three commonly used FACTS controllers: controllable series capacitors (CSCs) controllable phase shifters (CPSs) and static var compensators (SVCs) have been used in this book to control the inter-area oscillations. The overview of linear system theory from the perspective of power system control is explained through examples. The damping control design is formulated as norm optimization problem. The H_infinity, H2 norm of properly defined transfer functions are minimized in linear matrix inequalities (LMI) framework to obtain desired performance and stability robustness. Both centralized and decentralized control structures are used. Usually the transmission of feedback signal from a remote location encounters delays making it difficult to control the system. Smith predictor based approach has been successfully explored in this book as a solution to such a problem. Robust Control in Power Systems will be valuable to academicians in the areas of power, control and system theory, as well as professionals in the power industry.

Robust Control System Networks

The Stuxnet computer virus, originally discovered in July 2010, qualified as a turning point for control system security. While the malware did not cause destructive damage outside its designated target, it hit the Western world like the Sputnik shock. The sophistication and aggressiveness of this computer virus was at a level that few people had anticipated. It simply popped up without warning, after 10 years of silence following the first malicious amateur-style cyber attack on wastewater control systems in Australia. Compared to office IT malware as we know it, this would be like going from 1980s-style password guessing to botnets in one step. It was, indeed, shocking. Instead of a learning curve for both the attackers and the defenders that the general development and trend of malware had been experiencing in the IT world, there was one big leap. Even if they had wanted to, operators of potential targets in critical infrastructure and in the private sector were not able to perform a similar leap in defense and protection. Despite years, reaching back to the turn of the millennium, of efforts and investments in control system security, governmental programs and organizations, industry standards, workgroups, conferences, risk assessments, and mitigation projects, the industrialized nations continue to face a significant threat from post-Stuxnet malware for which they are by no means prepared.