Search results for "020209 energy"
showing 10 items of 1300 documents
Robust control for high performance induction motor drives based on partial state-feedback linearization
2019
This paper deals with a robust input-output feedback linearization control technique for induction motors. Indeed, classic feedback linearization presents two main disadvantages: 1) the accuracy of the dynamic model; and 2) the corresponding correct knowledge of the model parameters. To address this issue, the linear controller has been substituted with a suitably controller designed to be robust to the variations of the main parameters of the induction motor, like stator and rotor resistances, and the three-phase magnetizing inductance. The proposed controller has been tested both in numerical simulation and experimentally on a suitably designed test setup. Moreover, it has been compared w…
A review of diagnostics and prognostics of low-speed machinery towards wind turbine farm-level health management
2016
Abstract Large wind farms are gaining prominence due to increasing dependence on renewable energy. In order to operate these wind farms reliably and efficiently, advanced maintenance strategies such as condition based maintenance are necessary. However, wind turbines pose unique challenges in terms of irregular load patterns, intermittent operation and harsh weather conditions, which have deterring effects on life of rotating machinery. This paper reviews the state-of-the-art in the area of diagnostics and prognostics pertaining to two critical failure prone components of wind turbines, namely, low-speed bearings and planetary gearboxes. The survey evaluates those methods that are applicabl…
Innovative method to estimate state of charge of the hydride hydrogen tank: application of fuel cell electric vehicles
2021
International audience; Significant attention has been paid to metal hydrides (MH) as an environmentally friendly and safe way to store hydrogen. This technology has considerable potential for the application of embedded hydrogen storage in fuel cell electric vehicles, but its widespread application faces a major problem in terms of estimating the remaining hydrogen amount in the tank. In this work, a new method is proposed for estimating the state of charge (SoC) of the hydrogen hydride tank (HHT) by application of piezoelectric material. The idea is to cover the entire inner wall of the metal-hydride tank with a layer of piezoelectric material. During the process of hydrogen absorption, t…
Modeling Energy Demand Aggregators for Residential Consumers
2013
International audience; Energy demand aggregators are new actors in the energy scenario: they gather a group of energy consumers and implement a demand- response paradigm. When the energy provider needs to reduce the current energy demand on the grid, it can pay the energy demand aggregator to reduce the load by turning off some of its consumers loads or postponing their activation. Currently this operation involves only greedy energy consumers like industrial plants. In this paper we want to study the potential of aggregating a large number of small energy consumers like home users as it may happen in smart grids. In particular we want to address the feasibility of such approach by conside…
Understanding the Importance of Proper Incentives for Critical Infrastructures Management – How System Dynamics Can Help
2016
International audience; Computer and information systems are now at the core of numerous critical infrastructures. However, their security management is by far not a trivial issue. Further, these systems, by their very nature, belong to the domain of complex systems, where system dynamics (SD) is an established method, which aims at modelling such systems, their analysis and understanding. Further, on this basis it enables simulation of various policies to properly manage complex systems. More precisely, through understanding of the basic elements of the whole mosaic and their interplay, proper incentives can be tested. And this is important, because proper incentives can lead to the desire…
Novel, automated, semi-industrial modular photobioreactor system for cultivation of demanding microalgae that produce fine chemicals - The next story…
2021
Abstract Recently, there has been increased interest in the use of microorganisms in the production of pharmaceuticals, nutraceuticals and energy supply products, which is due to their rapid growth rate and ability to biosynthesize fine chemicals or biotransform specific xenobiotics. To achieve the desired scale of production and optimization of microbial cultures, it is necessary to design bioreactors that enable process automation, control of working parameters, reduction of microbial and chemical contaminations, and culture independence of climate conditions. In response to this need, an original, modular airlift-type photobioreactor system was designed and manufactured. This novel semit…
Renewable energies, business models and local growth
2018
Abstract Energy is one of the driving factors of the world economy: energy consumption is closely linked to quality of life and environmental impact. Reducing the use of fossil fuels, curtailing greenhouse gas emissions, and cutting energy dependence from traditional energy producing countries are the cornerstones of European policies for safe, competitive, sustainable, and renewable energy. In addition, the pressing need to provide new and diversified opportunities for supplementary income for the agricultural sector has fueled the desire to engage rural areas in this process. Biogas, derived from the anaerobic digestion of biomass, is one of the renewable energy sources that has been very…
Do Price Barriers Exist in the European Carbon Market?
2017
ABSTRACTIt is generally thought that psychological prices in markets primarily traded by professional participants should play a limited role. The authors investigate the existence of key reference points in the European Carbon Market, which can be considered as a market with highly qualified stakeholders. They document the presence of key levels and barrier bands around European Union Allowances (EUA) prices. It appears that traders tend to consider these price levels as resistances in upward movements and as supports in downward movements. Furthermore, the authors have observed that the existence of price barriers affects both return and volume dynamics. Therefore, the results indicate th…
Competition for long-haul connecting traffic among airports in Europe and the Middle East
2017
Abstract This paper analyzes the competitive position of major hub airports in Europe and the Middle East for long-haul connecting traffic. We apply a connection builder to construct competitive flight connections. A stand out feature of the proposed connection builder is the calibration of the model parameters using booking data, composed of actual passenger demand between a given origin and destination (O&D) market. The methodology is applied to measure competition between hubs using flight schedule data to calculate connectivity measures like the number of city-pairs connected via a hub airport. Our results show that the Middle Eastern hubs have improved their competitive position, while…
Using a hazard-independent approach to understand road-network robustness to multiple disruption scenarios
2021
Abstract A range of predictable and unpredictable events can cause road perturbations, disrupting traffic flows and more generally the functioning of society. To manage this threat, stakeholders need to understand the potential impact of a multitude of predictable and unpredictable events. The present paper adopts a hazard-independent approach to assess the robustness (ability to maintain functionality despite disturbances) of the Sioux Falls network to all possible disruptions. This approach allows understanding the impact of a wide range of disruptive events, including random, localised, and targeted link failures. The paper also investigates the predictability of the link combinations wh…