Power system stabilizers (PSSs) provide the most economical way to improve damping of electro-mechanical oscillations in electrical power systems. Synchrophasor technology enables the use of remotely measured signals in the PSS allowing for greater flexibility in the design of the PSS. Issues related to the transmission of remote signals should be addressed before implementing such systems in practice. This study investigates two of the data transmission issues: (i) delays, and (ii) data dropout; using a synchrophasor-based PSS designed for a two-area four-generator power system model. A time delayed system is modeled using discrete transformation and the effect of the constant delay on the control action of improving damping of an electro-mechanical oscillation is determined analytically. The effect of random delays and data dropout is investigated using non-linear simulations considering viable remedies to overcome these effects. This research also identifies effective means of using synchrophasor signals for improving the performance of PSSs. Primarily, this research introduces a novel control design algorithm based on eigenstructure assignment that could utilize remotely measured signals to design a robust PSS considering different operating conditions at the design stage. Remote signals could be used as additional inputs to the controller, which introduces extra degrees of freedom. In eigenstructure assignment, these additional degrees of freedom are used to assign eigenvalues and eigenvectors to have adequate damping performance of the system over different operating conditions. The algorithm is formulated as a derivative-free non-linear optimization problem and solved using a single step of optimization by eliminating the use of eigenvalue sensitivities. The proposed algorithm is tested for the 68 bus model of the interconnected New England test system and New York power system. Three different control configurations that use local and remote signals are considered in the design. The algorithm is solved using non-linear simplex optimization considering different initial points for seeking a global solution. Delays in the remote signals are also incorporated into the design. The designed controllers are verified in a non-linear simulation platform. Finally, the reliability of synchrophasor-based PSS is discussed in brief. / February 2016

Dans le secteur médical tout particulièrement, la qualité du geste est primordiale et les professionnels doivent être formés par la pratique pour acquérir un niveau de compétences compatible avec l'exercice de leur métier. Depuis une dizaine d'année, les simulateurs informatiques aident les apprenants dans de nombreux apprentissages mais ils doivent encore être associés à des travaux pratiques sur mannequins, animaux ou cadavres, qui pourtant n'offrent pas toujours suffisamment de réalisme par rapport aux vrais patients, et sont coûteux à l'usage. Aussi, leur formation s'achève généralement sur de vrais patients, ce qui présente des risques. Les simulateurs haptiques (fournissant une sensation d'effort) deviennent aujourd'hui une solution plus appropriée car ils peuvent reproduire des efforts résistant réalistes et proposer une infinité de cas d'étude pré-enregistrés. Cependant, apprendre seul sur un simulateur n'est pas toujours aussi efficace qu'un apprentissage "à quatre mains" (celles de l'instructeur et de l'apprenant manipulant les mêmes outils en coopération). Cette étude propose donc un système haptique de formation pratique à deux utilisateurs : l'instructeur et l'apprenant, interagissant chacun à travers leur propre interface haptique. Ils collaborent ainsi, avec des outils et un environnement de travail soit réels (l'outil est manipulé par un robot) soit virtuels. Une approche énergétique, faisant appel notamment à la modélisation par port-Hamiltonien, a été utilisée pour garantir la stabilité et la robustesse du système. Une étude comparative (en simulation) avec deux autres systèmes haptiques multi utilisateurs a montré l'intérêt de ce nouveau système pour la formation pratique. Il a été développé et validé expérimentalement sur des interfaces à un seul degré de liberté. Son extension à six degrés de liberté est facilitée par les choix de modélisation. Afin de pouvoir utiliser le système quand les deux protagonistes sont éloignés, cette étude propose des pistes d'amélioration qui ne sont pas encore optimisées. / More particularly in the medical field, gesture quality is primordial. Professionals have to follow hands-on trainings to acquire a sufficient level of skills in the call of duty. For a decade, computer based simulators have helped the learners in numerous learnings, but these simulations still have to be associated with hands-on trainings on manikins, animals or cadavers, even if they do not always provide a sufficient level of realism and they are costly in the long term. Therefore, their training period has to finish on real patients, which is risky. Haptic simulators (furnishing an effort feeling) are becoming a more appropriated solution as they can reproduce realist efforts applied by organs onto the tools and they can provide countless prerecorded use cases. However, learning alone on a simulator is not always efficient compared to a fellowship training (or supervised training) where the instructor and the trainee manipulate together the same tools. Thus, this study introduces an haptic system for supervised hands-on training: the instructor and the trainee interoperate through their own haptic interface. They collaborate either with a real tool dived into a real environment (the tool is handled by a robotic arm), or with a virtual tool/environment. An energetic approach, using in particular the port-Hamiltonian modeling, has been used to ensure the stability and the robustness of the system. This system has been designed and validated experimentally on a one degree of freedom haptic interface. A comparative study with two other dual-user haptic systems (in simulation) showed the interest of this new architecture for hands-on training. In order to use this system when both users are away from each other, this study proposes some enhancements to cope with constant communication time delays, but they are not optimized yet.