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.

PMU configuration for system dynamic performance measurement in large, multiarea power systems

Abstract: Effective assessment of the dynamic performance of the power system requires wide-area information from properly distributed phasor measurement units (PMUs). However, to maximize the information content of the captured signals, the sensors need to be located appropriately, with due account given to the structural properties underlying the given system. In this paper, two numerical algorithms are proposed to achieve this goal. They aim to maximize the overall sensor response while minimizing the correlation among sensor outputs so as to minimize the redundant information provided by multiple sensors. The sensor responses of interest are the bus voltage magnitude, and the angle and frequency coherency indexes, which are estimated by means of a statistical sampling of power system response signals from a transient-stability program. Through the "successive addition" scheme, one of these algorithms easily incorporates mandatory locations such as tie-line busses and large generator step-up transformers. The proposed approaches are first illustrated on the Hydro-Quebec transmission grid and then on a 9-area/67-bus/23-machine test network designed with well-defined geographical boundaries and pre-specified weak interties between electrically coherent areas.

Adaptive Phasor and Frequency-Tracking Schemes for Wide-Area Protection and Control

Abstract: The steady-state performance of phasor measurement units (PMUs) is well standardized in the recently issued revised IEEE Std. C37.118. The Western Electricity Coordinating Council (WECC) has developed dynamic performance requirements for PMU filters as a means to guarantee better, uniform PMU response under dynamic conditions, such as power swings and changing harmonics. These have been endorsed by North American Synchrophasor Initiative (NASPI) for its wide-area monitoring infrastructure. The main purpose of this paper is to present a new framework for designing PMU filtering algorithms capable of meeting or exceeding the WECC/NASPI requirements, while achieving an optimum transient response time. To this end, an adaptive complex bandpass filter derived from the exponentially modulated filter bank theory has been devised. It is built from freely chosen low-pass filter prototypes that fulfill the WECC requirements. The static and dynamic performances of two specific schemes dedicated to control and monitoring with 4- and 7-cycle response-time, respectively, are ascertained under noisy waveforms and changing harmonics with system frequency varying from 40 to 80 Hz. The center-frequency adaptation approach is shown to be intrinsically superior to the frequency compensation scheme, especially under fast varying frequency and changing harmonics.

Compatibility of N-Methyl-N-propylpyrrolidinium Cation Room-Temperature Ionic Liquid Electrolytes and Graphite Electrodes

Abstract: To realize high-safety, high-performance lithium ion secondary batteries using room-temperature ionic liquids, we examined [graphite electrode|room-temperature ionic liquid−lithium salt binary electrolyte|lithium metal electrode] cells by varying the cation structure of the room-temperature ionic liquid. In particular, a bis(fluorosulfonyl)imide anion based room-temperature ionic liquid cell showed high charge/discharge capacity and reversibility. By application of electrochemical calorimetric measurements during charge/discharge operation, the formation of a suitable interfacial layer, such as a solid electrolyte interphase between the graphite electrode and the room-temperature ionic liquid−lithium salt binary electrolyte was indicated. Moreover, we found that not only the anion structure but also the cation structure was important for the suitable charge/discharge of the graphite electrode.