Showing papers by "Hydro-Québec published in 2019"

Power System Dynamic State Estimation: Motivations, Definitions, Methodologies, and Future Work

Abstract: This paper summarizes the technical activities of the Task Force on Power System Dynamic State and Parameter Estimation. This Task Force was established by the IEEE Working Group on State Estimation Algorithms to investigate the added benefits of dynamic state and parameter estimation for the enhancement of the reliability, security, and resilience of electric power systems. The motivations and engineering values of dynamic state estimation (DSE) are discussed in detail. Then, a set of potential applications that will rely on DSE is presented and discussed. Furthermore, a unified framework is proposed to clarify the important concepts related to DSE, forecasting-aided state estimation, tracking state estimation, and static state estimation. An overview of the current progress in DSE and dynamic parameter estimation is provided. The paper also provides future research needs and directions for the power engineering community.

Hydrogen Storage for Mobility: A Review

Abstract: Numerous reviews on hydrogen storage have previously been published. However, most of these reviews deal either exclusively with storage materials or the global hydrogen economy. This paper presents a review of hydrogen storage systems that are relevant for mobility applications. The ideal storage medium should allow high volumetric and gravimetric energy densities, quick uptake and release of fuel, operation at room temperatures and atmospheric pressure, safe use, and balanced cost-effectiveness. All current hydrogen storage technologies have significant drawbacks, including complex thermal management systems, boil-off, poor efficiency, expensive catalysts, stability issues, slow response rates, high operating pressures, low energy densities, and risks of violent and uncontrolled spontaneous reactions. While not perfect, the current leading industry standard of compressed hydrogen offers a functional solution and demonstrates a storage option for mobility compared to other technologies.

Building Better Batteries in the Solid State: A Review.

Abstract: Most of the current commercialized lithium batteries employ liquid electrolytes, despite their vulnerability to battery fire hazards, because they avoid the formation of dendrites on the anode side, which is commonly encountered in solid-state batteries. In a review two years ago, we focused on the challenges and issues facing lithium metal for solid-state rechargeable batteries, pointed to the progress made in addressing this drawback, and concluded that a situation could be envisioned where solid-state batteries would again win over liquid batteries for different applications in the near future. However, an additional drawback of solid-state batteries is the lower ionic conductivity of the electrolyte. Therefore, extensive research efforts have been invested in the last few years to overcome this problem, the reward of which has been significant progress. It is the purpose of this review to report these recent works and the state of the art on solid electrolytes. In addition to solid electrolytes stricto sensu, there are other electrolytes that are mainly solids, but with some added liquid. In some cases, the amount of liquid added is only on the microliter scale; the addition of liquid is aimed at only improving the contact between a solid-state electrolyte and an electrode, for instance. In some other cases, the amount of liquid is larger, as in the case of gel polymers. It is also an acceptable solution if the amount of liquid is small enough to maintain the safety of the cell; such cases are also considered in this review. Different chemistries are examined, including not only Li-air, Li–O2, and Li–S, but also sodium-ion batteries, which are also subject to intensive research. The challenges toward commercialization are also considered.

Recent Progress on Organic Electrodes Materials for Rechargeable Batteries and Supercapacitors.

Abstract: Rechargeable batteries are essential elements for many applications, ranging from portable use up to electric vehicles. Among them, lithium-ion batteries have taken an increasing importance in the day life. However, they suffer of several limitations: safety concerns and risks of thermal runaway, cost, and high carbon footprint, starting with the extraction of the transition metals in ores with low metal content. These limitations were the motivation for an intensive research to replace the inorganic electrodes by organic electrodes. Subsequently, the disadvantages that are mentioned above are overcome, but are replaced by new ones, including the solubility of the organic molecules in the electrolytes and lower operational voltage. However, recent progress has been made. The lower voltage, even though it is partly compensated by a larger capacity density, may preclude the use of organic electrodes for electric vehicles, but the very long cycling lives and the fast kinetics reached recently suggest their use in grid storage and regulation, and possibly in hybrid electric vehicles (HEVs). The purpose of this work is to review the different results and strategies that are currently being used to obtain organic electrodes that make them competitive with lithium-ion batteries for such applications.

Real-Time Multiple Event Detection and Classification in Power System Using Signal Energy Transformations

Abstract: Real-time multiple event analysis is important for reliable situational awareness and secure operation of the power system. Multiple sequential events can induce complex superimposed pattern in the data and are challenging to analyze in real time. This paper proposes a method for accurate detection, temporal localization, and classification of multiple events in real time using synchrophasor data. For detection and temporal localization, a Teager–Kaiser energy operator (TKEO) based method is proposed. For event classification, a time series classification based method using energy similarity measure (ESM) is proposed. The proposed method is tested for simulated multiple event cases in the IEEE-118 bus system using DigSilent/PowerFactory and real PMU data for the Indian grid.

Alternative Dielectric Fluids for Transformer Insulation System: Progress, Challenges, and Future Prospects

Abstract: Ester-based dielectric fluids have gained widespread popularity for applications in high voltage apparatus. Synthetic and natural esters have been subjected to research for decades vis-a-vis mineral insulating oils around the world. Although many researchers favor the application of ester fluids, utilities are still uncertain and application of these alternatives remains a challenge. The intent of this survey is to present recent research progress and highlight the state of the art of key aspects that should be emphasized in future research. The contemporary research scenarios pertaining to the performance of ester fluids versus mineral oils, miscibility, and retrofilling of insulating fluids are discussed. In addition, pre-breakdown phenomena, usage of esters in on-load tap changers, environmental and fire resistance properties, and use of esters in cold climates are also discussed. Importantly, challenges and future aspects that should be investigated to improve the existing knowledge of ester dielectric fluids for applications in transformer technology are highlighted.

Low-tortuosity and graded lithium ion battery cathodes by ice templating

Abstract: Preserving high energy densities of batteries at fast charge and discharge rates at the cell-stack level is a critical challenge for applications such as electric vehicles. Current manufacturing methods usually produce lithium (Li) ion battery electrodes <100 μm thin with unavoidable tortuous internal porosity that reduces energy densities at fast rates. Here, we use ice templating to manufacture ultra-thick (900 μm) LiFePO4-based cathodes containing fast ion transport pathways and a pore structure gradient through the electrode thickness that promote high energy densities at fast rates. The electrodes exhibit 94 mA h g−1 at an ultra-high current density of 15 mA cm−2 (67% higher gravimetric energy density at the cell-stack level including inactive components) compared with 47 mA h g−1 for conventional electrodes containing random structures and the same materials. X-ray computed tomography and modeling are used to quantify the electrode structure within different sub-domains and along orthogonal directions, which directly rationalizes the excellent dynamic performance. The electrode microstructure design, manufacturing method and characterization tools will be of use for other energy storage and conversion devices that rely on fast directional mass transport.

Dams have varying impacts on fish communities across latitudes: a quantitative synthesis

Abstract: Dams are recognised to impact aquatic biodiversity, but the effects and conclusions diverge across studies and locations. By using a meta-analytical approach, we quantified the effects of impoundment on fish communities distributed across three large biomes. The impacts of dams on richness and diversity differed across biomes, with significant declines in the tropics, lower amplitude but similar directional changes in temperate regions, and no changes in boreal regions. Our analyses showed that non-native species increased significantly in tropical and temperate regulated rivers, but not in boreal rivers. In contrast, temporal trajectories in fish assemblage metrics were common across regions, with all biomes showing an increase in mean trophic level position and in the proportion of generalist species after impoundment. Such changes in fish assemblages may affect food web stability and merit closer study. Across the literature examined, predominant mechanisms that render fish assemblages susceptible to impacts from dams were: (1) the transformation of the lotic environment into a lentic environment; (2) habitat fragmentation and (3) the introduction of non-native species. Collectively, our results highlight that an understanding of the regional context and a suite of community metrics are needed to make robust predictions about how fish will respond to river impoundments.

In situ observation of solid electrolyte interphase evolution in a lithium metal battery

Abstract: Lithium metal is a favorable anode material in all-solid Li-polymer batteries because of its high energy density. However, dendrite formation on lithium metal causes safety concerns. Here we obtain images of the Li-metal anode surface during cycling using in situ scanning electron microscopy. Constructing videos from the images enables us to monitor the failure mechanism of the battery. Our results show the formation of dendrites on the edge of the anode and isles of decomposed lithium bis(trifluoromethanesulfonyl)imide on the grain boundaries. Cycling at high rates results in the opening of the grain boundaries and depletion of lithium in the vicinity of the isles. We also observe changes in the surface morphology of the polymer close to the anode edge. Extrusion of lithium from these regions could be evidence of polymer reduction due to a local increase in temperature and thermal runaway assisting in dendrite formation. Dendrite formation on lithium metal anodes jeopardizes the safety of lithium ion batteries. Here the authors use in situ scanning electron microscopy to follow the evolution of dendrites and isles of a conductive salt forming on the anode surface, causing the battery to fault.

Emerging Risk Management in Industry 4.0: An Approach to Improve Organizational and Human Performance in the Complex Systems

Abstract: Industry 4.0 in the contemporary operating context carries important sources of complexity. This context generates both traditional risks and emerging risks that must be managed. The management of these risks includes both industrial risks and occupational risks, since they are heavily interlinked. The human factor can be considered the main link between both types of risks. Thus, understanding risks originating from human errors and organizational weaknesses as causes of accidents and other disruptions in complex systems requires elaborating sophisticated modeling approaches. Therefore, the objective of this paper is to propose an organizational and human performance approach to improve the emerging risk management linked to the complex systems, like as Human-Machine Interactions (HMI) and Human-Robot Interaction (HRI). To fulfill this objective, we first introduce the concept of emerging risk linked to human factor. Then, we introduce the concept of emerging risk management in the Industry 4.0 context. Under this complex context, we expose the concept considering the current models of risk management. Finally, we discuss how enhancing human and organizational performance can be achieved through risk management in complex systems linked to Industry 4.0. Therefore, we conclude that while Industry 4.0 brings numerous advantages, it must contend with emerging risks and challenges associated with organizational and human factors. These emerging risks include industrial risks as well as occupational risks. Moreover, the human factor aspect of Industry 4.0 is directly linked to industrial emerging and occupational emerging via context of operations. To cope with these new challenges, it is necessary to develop new approaches. One of such approaches is Complex System Governance. This approach is discussed along with the need for adequate organizational and human performance models dealing with, for example, experience from other domains such as nuclear, space, aviation, and petrochemical.

A Generic EMT-Type Model for Wind Parks With Permanent Magnet Synchronous Generator Full Size Converter Wind Turbines

Abstract: Utilities are under considerable pressure to increase the share of wind energy resources in their generation fleet. With the increasing share of wind energy resources, the dynamic behavior of power systems will change considerably due to fundamental differences in technologies used for wind and conventional generators. There is a very little standardization in the ways to model wind turbines (WTs) and wind parks (WPs) in sharp contrast to conventional power plants. Hence, there is an international interest to deliver generic models (i.e. standardized and publicly available) for WTs and WPs that are able to capture all performance aspects as good as manufacturer-specific models. This paper presents an electromagnetic transient (EMT) simulation model for full-size converter (FSC) WT-based WPs that can be used for stability analysis and interconnection studies. The considered topology uses a permanent magnet synchronous generator. Although the collector grid and the FSC WTs are represented with their aggregated models, the overall control structure of the WP is preserved. FSC WT and WP control systems include the non-linearities, and necessary transient and protection functions to simulate the accurate transient behavior of WPs.

Corrosion and wear properties of FeCrMnCoSi HVOF coatings

Abstract: FeCrMnCoSi coating (so-called CaviTec alloy) is recognized as an efficient protective measure to extend the service-life of steel components subjected to severe cavitation erosion. Besides this requirement, many applications also demand coatings with proper corrosion and wear resistances. The aim of this study is to evaluate the pitting corrosion and the sliding wear resistances of CaviTec coatings produced by high-velocity oxygen fuel (HVOF) and deposited onto a 304 stainless steel (SS). The corrosion performances in simulated seawater indicated that these coatings exhibit satisfactory corrosion resistance with regions around the inter-splats representing the preferential weak links sites for pitting corrosion initiation. CaviTec coating wear is characterized by mild delamination followed by severe abrasive wear once the hard-martensitic debris are added in the tribosystem due to the transformation induced plasticity (TRIP) effect. Corrosion and wear results point out that the CaviTec coatings, originally developed to possess high cavitation erosion resistance, also present satisfactory corrosion resistance in seawater-like medium and interesting dry sliding wear performance, which can extend their application domain.

Integrating Batteries in the Future Swiss Electricity Supply System: A Consequential Environmental Assessment

Abstract: Stationary batteries are projected to play a role in the electricity system of Switzerland after 2030. By enabling the integration of surplus production from intermittent renewables, energy storage units displace electricity production from different sources and potentially create environmental benefits. Nevertheless, batteries can also cause substantial environmental impacts during their manufacturing process and through the extraction of raw materials. A prospective consequential life cycle assessment (LCA) of lithium metal polymer and lithium‐ion stationary batteries is undertaken to quantify potential environmental benefits and drawbacks. Projections are integrated into the LCA model: Energy scenarios are used to obtain marginal electricity supply mixes, and projections about the battery performances and the recycling process are sourced from the literature. The roles of key parameters and methodological choices in the results are systematically investigated. The results demonstrate that the displacement of marginal electricity sources determines the environmental implications of using batteries. In the reference scenario representing current policy, the displaced electricity mix is dominated by natural gas combined cycle units. In this scenario, the use of batteries generates environmental benefits in 12 of the 16 impact categories assessed. Nevertheless, there is a significant reduction in achievable environmental benefits when batteries are integrated into the power supply system in a low‐carbon scenario because the marginal electricity production, displaced using batteries, already has a reduced environmental impact. The direct impacts of batteries mainly originate from upstream manufacturing processes, which consume electricity and mining activities related to the extraction of materials such as copper and bauxite.

A Manganese Hydride Molecular Sieve for Practical Hydrogen Storage Under Ambient Conditions

Abstract: A viable hydrogen economy has thus far been hampered by the lack of an inexpensive and convenient hydrogen storage solution meeting all requirements, especially in the areas of long hauls and delivery infrastructure. Current approaches require high pressure and/or complex heat management systems to achieve acceptable storage densities. Herein we present a manganese hydride molecular sieve that can be readily synthesized from inexpensive precursors and demonstrates a reversible excess adsorption performance of 10.5 wt% and 197 kgH2 m−3 at 120 bar at ambient temperature with no loss of activity after 54 cycles. Inelastic neutron scattering and computational studies confirm Kubas binding as the principal mechanism. The thermodynamically neutral adsorption process allows for a simple system without the need for heat management using moderate pressure as a toggle. A storage material with these properties will allow the DOE system targets for storage and delivery to be achieved, providing a practical alternative to incumbents such as 700 bar systems, which generally provide volumetric storage values of 40 kgH2 m−3 or less, while retaining advantages over batteries such as fill time and energy density. Reasonable estimates for production costs and loss of performance due to system implementation project total energy storage costs roughly 5 times cheaper than those for 700 bar tanks, potentially opening doors for increased adoption of hydrogen as an energy vector.

Lithium Photo‐intercalation of CdS‐Sensitized WO3 Anode for Energy Storage and Photoelectrochromic Applications

Abstract: Integration of solar-energy harvesting and storage functions has attracted significant research attention, as it holds promise for ultimate development of light-chargeable devices. In this context, a functional nanocomposite anode that not only permits electrochemical energy storage through Li-ion photo-intercalation, but also exhibits potential for photoelectrochromic applications, was investigated. The nanocomposite is made of the Li-ion intercalation compound WO3 , thinly coated with TiO2 and sensitized by the photoactive semiconductor CdS. During light exposure, the photoelectrons from CdS are transported to the WO3 /electrolyte interface, where Li-ion intercalation takes place. Photoelectron transport is facilitated by the interfacial TiO2 layer. The WO3 was shown to be functional in multiple photocharge-discharge cycles, but the CdS suffers from degradation and photocorrosion. Hence, the selection of compatible semiconductors and protective coating strategies should be pursued to overcome these issues.

Optimal Cost of Voltage Security Control Using Voltage Dependent Load Models in Presence of Demand Response

Abstract: This paper proposes a new framework for corrective voltage control (CVC) of power systems. It ensures a desired loading margin (LM) after encountering severe contingencies while minimizing the corresponding control costs. The framework is divided into primary CVC (PCVC) and secondary CVC (SCVC) stages for restoration of voltage stability and ensuring a desired LM. These stages are based on the sequence and quickness of the control actions required in post-contingency state of the system. The PCVC sub problem deals with the condition faced by a power system subject to voltage instability as the result of severe contingencies. Such control is merely devised to restore system stability. Next, in the SCVC sub problem that follows PCVC, the system operating point is modified such that a desired LM is ensured, and hence voltage security of the system is achieved. The active and reactive power redispatch of generation units and involuntary load curtailment are employed along with the voluntary demand-side participations as control facilities in PCVC and SCVC sub problems, by deploying a proper voltage dependent static model for loads. The proposed framework is examined on the IEEE 118-bus system. The numerical results substantiate the effectiveness of the proposed approach.

Functionalization of the carbon additive of a high-voltage Li-ion cathode

Abstract: We report on the improved stability of high-voltage composite cathodes for lithium-ion batteries by chemical modification of the carbon additive, acetylene black, using diazonium chemistry with C6H4CF3, C6H4SO3H, C6H4COOH and C6H4N(C2H5)2 groups. Elemental analysis and X-ray photoelectron spectroscopy confirmed the presence of substituted aryl groups at the surface of the carbon. The electrochemical behavior of functionalized and unmodified carbon electrodes was investigated by cyclic voltammetry, galvanostatic cycling and electrochemical impedance spectroscopy. The irreversible capacity between 4.5 and 5.3 V vs. Li/Li+ strongly diminished after modification. The different functionalized carbons were utilized as a conductive additive in a high-voltage LiMn1.5Ni0.5O4 (LMN) cathode. Improved capacity retention was observed for LMN composite cathodes with modified carbons, as well as lower charge-transfer resistance determined after polarization for several hours at a constant voltage of 5.3 V. These observations were attributed to the presence of the grafted groups on the carbon additive, which inhibit the degradation of the electrolyte and the carbon, as demonstrated by X-ray photoelectron spectroscopy measurements of electrodes following charge/discharge cycling.