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.

Type-III Wind Power Plant Harmonic Emissions: Field Measurements and Aggregation Guidelines for Adequate Representation of Harmonics

Abstract: Large wind power plants (WPPs) based on variable speed turbines produce harmonics and interharmonics of voltage and current. This paper presents some generic guidelines about resulting harmonics and interharmonics at the high voltage point of interconnection (POI) of a type-III WPP. These guidelines are supported by both field measurements and time-domain electromagnetic transient (EMT) simulations. Specific focus is placed on how these harmonics and interharmonics can be represented in EMT simulation using detailed and aggregated models of a WPP. First, a theoretical explanation of the origin of all frequencies produced by a type-III wind generator (WG) is presented. The results of field measurements from a large WPP are then reported and analyzed confirming the theory. Subsequently, the field measurements are compared to simulation results of a detailed EMT model of the entire WPP and differences are explained. Finally, aggregated models of the same WPP are established and the accuracy of these aggregated models is discussed in light of the specific need of time-domain EMT studies that require adequate representation of harmonics.

Overview of olivines in lithium batteries for green transportation and energy storage

Abstract: We present the progress on the physical chemistry of the olivine compounds since the pioneering work of Prof. John Goodenough. This progress has allowed LiFePO4 to become the active cathode element of a new generation of Li-ion batteries that makes a breakthrough in the technology of the energy storage and electric transportation. This achievement is the fruit of about a decade of intensive research in the electrochemical community during which chemists, electrochemists, and physicists added there efforts to understand the properties of the material, to overcome the obstacles that were met on the way, and finally to reach the state of the art that allows its commercial use for worldwide applications in the industry today. These obstacles involved carbon coating, purification, control of the surface, the progressive decrease of the size of the particles down to nanoscale, and comprehensive investigation of surface effects. Nevertheless, heterogeneity in the quality of the product available on the market is damaging and may even be an obstacle to the development of new demanding technologies such as electric transportation. Emphasis is placed on the quality control that is needed to guarantee the reliability and the optimum electrochemical performance of this material as the active cathode element of Li-ion batteries. The route to increase the performance of Li-ion batteries with the other members of the family is also discussed. Since Prof. John Goodenough not only initiated the work but also played a major role in the research and development on these materials through the years, the present review is dedicated to him.

Phosphate Polyanion Materials as High-Voltage Lithium-Ion Battery Cathode: A Review

Abstract: Followed by decades of successful efforts in developing cathode materials for high specific capacity lithiumion batteries, currently the attention is on developing a high voltage battery (>5 V vs Li/Li+ ) with an aim to increase the energy density for their many fold advantages over conventional <4 V batteries. Among the various cathode materials, phosphate polyanion materials (LiMPO4, where M is a single metal or a combination of metals) showed promising candidacy given their high electrochemical potential (4.8−5 V vs Li/Li+), long cycle stability, low cost, and achieved specific capacity (∼165 mAh·g−1) near to its theoretical limit (170 mAh·g−1). In this review, factors affecting the electrochemical potential of the cathode materials are reviewed and discussed. Techniques to improve the electrical and ionic conductivities of phosphate polyanion cathodes, namely, surface coating, particle size reduction, doping, and morphology engineering, are also discussed. A processing−property correlation in phosphate polyanion materials is also undertaken to understand relative merits and drawbacks of diverse processing techniques to deliver a material with targeted functionality. Strategies required for high-voltage phosphate polyanion cathode materials are envisioned, which are expected to deliver lithium-ion battery cathodes with higher working potential and gravimetric specific capacity