Hydro-Québec

About: Hydro-Québec is a government organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Electric power system & Dielectric. The organization has 2596 authors who have published 4433 publications receiving 100878 citations.

Catastrophe Predictors From Ensemble Decision-Tree Learning of Wide-Area Severity Indices

Abstract: Catastrophe precursors are essential prerequisites for response-based remedial action schemes, at both the protective and the operator levels In this paper, wide-area-severity indices (WASI) derived from PMU measurements serve as the basis for building fast catastrophe predictors using random-forest (RF) learning Given the randomness in the ensemble of decision trees (DTs) stacked in the RF model, it can provide at the recall stage not only an early assessment of the stable/unstable status of an ongoing contingency but also a probability outcome which quantifies the confidence level of the decision This methodology, which to the best of our knowledge is new to the dynamic security assessment (DSA) of power systems, is also very effective in evaluating the importance of and interaction among the various WASI input features Our research unexpectedly showed that the ensemble of trees in the RF is very robust in the presence of small changes in the training data and generalize across widely different network dynamics Thus, the same RF performed very well on a large database with more than 60 000 instances from a test system (10%) and an actual (90%) system combined One such a general RF (with 210 trees) boosted the reliability of a 9-cycle catastrophe predictor to 999%, compared to only 70% when a single conventionally trained DT is used

Robust design and coordination of multiple damping controllers using nonlinear constrained optimization

Abstract: This paper proposes a design approach for power system stabilizing controllers based on parameter optimization of compensators with generalized structures. It shows that a selective modal performance index is an improved measure of the stabilizing effect of a given design, although its blind minimization can end in a useless local minimum. Adding stability, sensitivity and robustness constraints greatly improve the engineering significance of the resulting design. The development is fully multivariable and remains sufficiently general to apply equally well to a feedback or cascade stabilizer, with any type of input signal or transfer function structure. Three examples are used: a robust PSS design for a single machine-infinite bus system with multiple operating points; multiple PSS coordination for a large system; and a coordinated design of four PSSs for the Kundur's two-area test system. All results show good prospects for the constrained optimization based approach to the design of robust stabilizers.

Transmission line maintenance robots capable of crossing obstacles: State-of-the-art review and challenges ahead

Abstract: Power line inspection and maintenance already benefit from developments in mobile robotics. This paper presents a comprehensive review of the state of the art. It focuses on mobile robots designed to cross obstacles found on a typical transmission line while using the conductor as support for traveling. Promising areas of research and development as well as challenges that remain to be solved are discussed with a view to developing fully autonomous technologies. Maintenance tasks, including inspection and repairs, are identified as high-value applications in transmission live-line work. Conclusions are drawn from experience, and the future of mobile robotics applied to transmission line maintenance is discussed. © 2009 Wiley Periodicals, Inc.