1,721,065 research outputs found
An MPC-based Energy Management System for a Hybrid Electric Vehicle
Full text linkA real-time Energy Management System (EMS) is presented in this paper, which aims at minimizing the operating costs of a Hybrid Electric Vehicle (HEV) equipped with different energy storage units (fuel cell, supercapacitors, batteries). The proposed EMS manages all HEV operating constraints properly through a Model Predictive Control (MPC) approach, which identifies the allowable ranges of each variable based on system modelling and actual HEV operating conditions. The optimization is then carried out by means of suitable look-up tables, which are accessed in accordance with the variable ranges previously computed. The effectiveness of the proposed MPC-based EMS is verified through numerical simulations, which also regard a rule-based EMS for comparison purposes
Development of a Matlab Application for the Preliminary Design of Electric Propulsion Systems
No full textThis paper presents an application for the preliminary design of Electric Propulsion Systems (EPSs) for Electric Vehicles (EVs). It is characterized by a friendly user interface developed using the Matlab tool AppDesigner that allows the imposition of the EV performance and the evaluation of the required EPS specification. Subsequently, the preliminary design of the Permanent Magnet Synchronous Machine (PMSM) and transmission system is obtained by imposing appropriate design targets, mechanical and electromagnetic constraints and operating conditions, and selecting machine materials. The PMSM design is validated through FEA analysis. This results in a useful tool for the design of EPS components, quick and easy to use
A Stochastic Approach to the Power Requirements of the Electric Vehicle Charging Infrastructure: The Case of Spain
Full text linkBattery electric vehicles represent a technological pathway for reducing carbon emissions in personal road transport. However, for the widespread adoption of this type of vehicle, the user experience should be similar to that of combustion engine vehicles. To achieve this objective, a robust and reliable public charging infrastructure is essential. In Spain, the electric recharging infrastructure is growing quickly in metropolitan areas but much more slowly on roads and highways. The upcoming charging stations must be located along high-volume traffic corridors and in proximity to the Trans-European Transport Network. The main contribution of this research is to offer a method for examining the essential electricity infrastructure investments required in scenarios involving substantial electric vehicle adoption. The methodology includes a sensitivity analysis of fleet composition and market share, recharging user behavior, charging station density, and vehicle efficiency improvements. To this end, the authors have developed a simplified probabilistic model, addressing the effect of the involved parameters through a comprehensive scenario analysis. The results show that the actual number of high-capacity charging plugs on Spanish roads is significantly lower than the European regulation requirements for the year 2030 considering an electric vehicle market share according to the Spanish Integrated National Energy and Climate Plan 2021-2030 objectives and it is far from the necessary infrastructure to cover the expected demand according to the traffic flow. Under these circumstances, the charging peak power demand reaches over 7.4% of the current Spanish total power demand for an electric vehicle fleet, which corresponds to only 12% of the total
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Flux-Weakening Space Vector Control Algorithm for Permanent Magnet Brushless DC Machines
No full textA Flux-Weakening Space Vector Control algorithm (FW-SVC) for Permanent Magnet Brushless DC Machine (PMBDCM) is presented in this paper. It is developed referring to a novel ft reference frame, which enables distinguishing field and torque current components clearly. Therefore, a voltage follower PI regulator has been introduced in order to synthesize the reference field current based on the DC-link voltage deficit. This goal requires coping with non-linearities of the PMBDCM model in order to achieve a suitable trade-off between dynamic and steady-state performances. The effectiveness of the proposed solution is verified through numerical simulations, which regard the comparison between the proposed FW-SVC and both a conventional Current Commutation Control (CCC) and an SVC with no field current injection
Electrification of Leisure Boats: a commercial State-of-the-Art
Full text linkThis paper presents the commercial state-of-the-art of electric leisure boats. Particularly, several kinds of electric propulsion systems for electric and full electric boats are considered and reviewed, by investigating the attendees of some of the most important international boat shows. The analysis highlights that the market proposes electric propulsion systems which cover a wide range of boats in terms of kinds, dimensions, and scopes. Similarly, a number of full electric boats are also available on the market, promising eco-friendly, efficient, exciting and quietly sailing experiences. The present overview focuses on motor and battery sizes, as well as on expected performance and optional systems, such as range extenders and hydrofoil systems
A Combined Planning and Design Approach of a Public Charging Infrastructure for Electric Vehicles
No full textA Combined Planning and Design approach (CPD) for a Public Charging Infrastructure (PCI) for Electric Vehicles (EVs) is presented in this paper. The aim is defining the displacement of charging infrastructures for easing early EV diffusion. The proposed CPD consists in a traffic/parking model that estimates the charging demand of potential EV owners for a given scenario. A coarse distribution of Charging Stations (CSs) over the selected Zones of Interest (ZOIs) is achieved at first, by taking into account the charging demand coverage. Subsequently, PCI structure is further and sequentially refined in order to comply with both urban and power system constraints, by minimizing installation cost at the same time. The proposed CPD is being employed for designing the PCI of the Italian island of Sardinia in order to support the adoption of EVs for commuting; its effectiveness is shown by some preliminary results that refer to a portion of the overall PCI
A multistage design procedure for planning and implementing public charging infrastructures for electric vehicles
Full text linkPresented in this paper is a Multistage Design Procedure (MSDP) for planning and implementing Public Charging Infrastructures (PCIs) to satisfy intracity charging demand of Electric Vehicles (EVs). The proposed MSDP splits planning and design processes into multiple stages, from macroscale to fine-scale levels. Consequently, the preliminary results achieved at each stage can be refined at the subsequent stages, leading to determine the accurate number and precise geographical location of each charging point. The main advantage of the proposed approach is that it splits a very complicated procedure into multiple and simpler stages, at each of which appropriate goals, targets and constraints can be included. As a result, the iterative interactions among all the stakeholders involved in the PCI design process are significantly simplified. The proposed MSDP has been employed in the planning and design of the PCI of the Italian island of Sardinia, accordingly to all the public bodies
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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