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.

Lateral Weir Flow Model

Abstract: The theory of flow through a lateral conduit outlet has been adopted to derive an expression for the discharge coefficient of the flow through a lateral weir set in a rectangular channel. The theoretical expressions hold good for subcritical flow in the channel upstream of the weir. The experimental data obtained in a test flume provide a verification of the theoretical relationships between the geometric and fluid dynamic parameters of the weir flow. The proposed relationships are valid for flow through lateral weirs that can be as wide as the parent channel.

Ensemble decision trees for phasor measurement unit-based wide-area security assessment in the operations time frame

Abstract: This study proposes ensemble decision trees for phasor measurement units (PMUs)-based wide-area security assessment to provide early warnings of deteriorating system conditions. In the proposed technique, the wide-area response signals in real-time operation are captured after 1 and 2 s fault clearing time, from the respective monitoring buses where PMUs are placed. These wide-area post-disturbance records are processed in time and frequency domains for extracting selected decision features such as the peak spectral density of the angle, frequency and their dot product evaluated over the grid areas called as wide-area severity indices (WASI). WASI are used as input features to train the random forests (RFs) to build effective predictor for early warnings in security assessment. The RF-based learning not only provides high performance accuracy but is also effective in valuing the importance of, and the interaction among, the various WASI input features, for developing the reliable predictor. The RF has been successfully tested for classifying both system-wise and area-wise NERC-compliant contingencies, using 55 196 cases (76 stable) from system operations studied on the Hydro Que bec network providing 99.9 reliability.

Density profiles, electric field and energy dissipation in a short gap breakdown: a two-dimensional model

Abstract: A two-dimensional model of the short gap breakdown in He has been developed consisting of conservation equations for electrons, ions and metastable atoms and the Poisson equation. Direct stepwise and Penning ionisation are considered and cathode emission takes into account the ion and metastable impact as well as photo-emission. Time development is followed up to 1.11 mu s, when the electron, ion and metastable densities reach maximum values of 1.6, 25 and 180 (*1010 cm-3) respectively.