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.

Corrosive Sulfur in Insulating Oils: Its Detection and Correlated Power Apparatus Failures

Abstract: Contamination of paper tapes by corrosive sulfur in insulating oils may cause shorting faults between turns. Typically, this occurs at higher temperature in the upper portions of the windings of shunt reactors and power transformers. In many of the tested oils, high amounts of dibenzyl-disulfide (DBDS) were found.

Recent developments in the applications of nanocrystalline materials to hydrogen technologies

Abstract: The paper discusses the application of nanocrystalline alloys as hydrogen storage materials and as electrocatalysts for solid polymer electrolyte fuel cells. After reviewing some of the requirements of metal hydrides for hydrogen fueled vehicles, the paper presents new results on the structure and hydrogen sorption properties of high storage capacity ball-milled magnesium hydride. The great advantages of milling the hydride instead of the pure metals for producing novel nanostructures with high surface area and for improving hydrogen sorption kinetics are presented. In the second part of the paper, the same technique has been extended to the milling of carbides and chlorides and coupled to a lixiviation process to produce new electrocatalysts for polymer electrolyte fuel cells. This new technology offers the possibility of producing nanoparticles with metastable structures whose specific surface area is much larger than that of any nanocrystalline powders made by conventional ball milling techniques. Pt-based nanoparticles were fabricated and tested as anode in fuel cells under pure and CO-contaminated hydrogen feedstreams.

A new fault location algorithm for radial transmission lines with loads

Abstract: Conventional fault location schemes do not take loads and their valuable impedance behavior into account. This leads to unacceptable errors in the case of radial transmission lines with loads, commonly found at the 120 Kv and lower levels. A new method for such lines is proposed in this paper. The fault distance is obtained by the solving an implicit equation. Single phase to ground, phase to phase and three phase to ground faults are treated. The effect of the new scheme is illustrated by simulated faults.

AC flashover performance of insulators covered with artificial ice

Abstract: A field observation of ice accretion on Hydro-Quebec HV insulators was carried out, as well as a laboratory investigation of the AC flashover performance of various types of insulators covered with artificial ice. The field observations made it possible to identify the type and physical aspect of naturally occurring ice accretions produced during freezing rain precipitation. The laboratory investigation was conducted in a 4.8/spl times/2.8 m/spl times/3.8 m climate room using a HV transformer of 120 kV, 240 kVA with a short-circuit impedance of 5%. A method based on the standard IEC 507 method was developed for measuring the maximum withstand voltage (V/sub WS/) of ice-covered insulators. Various factors were investigated, including the effects on the insulator V/sub WS/ of such particulars as type, thickness, and uniformity of the ice, as well as the arcing distance of the insulators and the conductivity of freezing water. The effects of uniform ice, 2 cm thick, on 5 IEEE insulator units was thus considered to be equivalent to the effect of an ESDD of about 0.13 mg/cm/sup 2/ on the same insulators. >