Review of Electric Vehicle Charging Technologies, Configurations, and Architectures

Electric Vehicles (EVs) are projected to be one of the major contributors to energy transition in the global transportation due to their rapid expansion. The EVs will play a vital role in achieving a sustainable transportation system by reducing fossil fuel dependency and greenhouse gas (GHG) emissions. However, high level of EVs integration into the distribution grid has introduced many challenges for the power grid operation, safety, and network planning due to the increase in load demand, power quality impacts and power losses. An increasing fleet of electric mobility requires the advanced charging systems to enhance charging efficiency and utility grid support. Innovative EV charging technologies are obtaining much attention in recent research studies aimed at strengthening EV adoption while providing ancillary services. Therefore, analysis of the status of EV charging technologies is significant to accelerate EV adoption with advanced control strategies to discover a remedial solution for negative grid impacts, enhance desired charging efficiency and grid support. This paper presents a comprehensive review of the current deployment of EV charging systems, international standards, charging configurations, EV battery technologies, architecture of EV charging stations, and emerging technical challenges. The charging systems require a dedicated converter topology, a control strategy and international standards for charging and grid interconnection to ensure optimum operation and enhance grid support. An overview of different charging systems in terms of onboard and off-board chargers, AC-DC and DC-DC converter topologies, and AC and DC-based charging station architectures are evaluated

Unification requirements of electric vehicle charging infrastructure

By increasingelectric vehicles in numbers and getting the public attention, availability, safety and accessibility of its charging infrastructure are key factorsto users’ satisfaction. Charging infrastructure in electric vehicle industry can have a role as an interface for exchanging information among other components as well. Currently, lack of universality in electric vehicle industry has caused anisolation in networks of electric vehicles. This isolationwill cause difficulty in having an aggregated set of information about electric vehicles and their consumption pattern. The paper reviews current charging infrastructure and the possibility of providing universality based on candidate protocols and technologies. © 2016 Institute of Advanced Engineering and Science

A comprehensive study of key Electric Vehicle (EV) components, technologies, challenges, impacts, and future direction of development

Abstract: Electric vehicles (EV), including Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Electric Vehicle (FCEV), are becoming more commonplace in the transportation sector in recent times. As the present trend suggests, this mode of transport is likely to replace internal combustion engine (ICE) vehicles in the near future. Each of the main EV components has a number of technologies that are currently in use or can become prominent in the future. EVs can cause significant impacts on the environment, power system, and other related sectors. The present power system could face huge instabilities with enough EV penetration, but with proper management and coordination, EVs can be turned into a major contributor to the successful implementation of the smart grid concept. There are possibilities of immense environmental benefits as well, as the EVs can extensively reduce the greenhouse gas emissions produced by the transportation sector. However, there are some major obstacles for EVs to overcome before totally replacing ICE vehicles. This paper is focused on reviewing all the useful data available on EV configurations, battery energy sources, electrical machines, charging techniques, optimization techniques, impacts, trends, and possible directions of future developments. Its objective is to provide an overall picture of the current EV technology and ways of future development to assist in future researches in this sector

Electric Vehicles Charging Management System for Optimal Exploitation of Photovoltaic Energy Sources Considering Vehicle-to-Vehicle Mode

The growing penetration of distributed renewable energy sources (RES) together with the increasing number of new electric vehicle (EV) model registrations is playing a significant role in zero-carbon energy communities’ development. However, the ever-larger share of intermittent renewable power plants, combined with the high and uncontrolled aggregate EV charging demand, requires an evolution toward new planning and management paradigms of energy districts. Thus, in this context, this paper proposes novel smart charging (SC) techniques that aim to integrate as much as possible RES generation and EV charging demand at the local level, synergically acting on power flows and avoiding detrimental effects on the electrical power system. To make this possible, a centralized charging management system (CMS) capable of individually modulating each charging power of plugged EVs is presented in this paper. The CMS aims to maximize the charging self-consumption from local RES, flattening the peak power required to the external grid. Moreover, the CMS guarantees an overall good state of charge (SOC) at departure time for all the vehicles without requiring additional energy from the grid even under low RES power availability conditions. Two methods that differ as a function of the EV power flow direction are proposed. The first SC only involves unidirectional power flow, while the second one also considers bidirectional power flow among vehicles, operating in vehicle-to-vehicle (V2V) mode. Finally, simulations, which are presented considering an actual case study, validate the SC effects on a reference scenario consisting of an industrial area having a photovoltaic (PV) plant, non-modulable electrical loads, and EV charging stations (CS). Results are collected and performance improvements by operating the different SC methods are compared and described in detail in this paper

Electric vehicle smart charging

In recent years, the number of electric vehicles (EVs) has been increasing. It will play more and more important role in the power grid operation because of its storage features, where charging and discharging control strategies and construction of the charging facilities are the priorities to be solved in this field. At the same time, the availability of the charging infrastructures is still limited and provides a promising application area for communication and control research. This thesis focuses on the control of the energy status offered by the buildings/houses providing a power management across the EV charging session. It also describes the development of a system to dynamically control the charging of EVs and maintain the operation of the power system by knowing the available power. To charge EVs a communication between the EV and the charging station is needed. The communication is based on the standard IEC61851, which specifies a pulse width modulation (PWM) signal that is sent to the EV to define the charging current. The system hardware consists of two modules, a charging station and a coordinator both with communication capabilities, while the power management algorithms are in a server, which then calculates the available power based on the power consumption behaviour and uses it to assign the charge of the EV. The system aims to control the EV charging session considering the power consumption to control their charging current. For the case of multiple EVs, the system will manage the charging session based on a priority level prioritizing the EV how started to charge first. The results shows the feasibility of the charging system approach to control the EV charging station considering the system power consumption and the introduction of the priority level for multiple EVs.Nos últimos anos, o número de veículos elétricos está aumentando. Eles desempenham um papel cada vez mais importante na operação da rede elétrica por causa do seu recurso de armazenamento, onde as estratégias do controlo de carregamento e descarregamento e a construção das instalações de carregamento são as prioridades a serem resolvidas neste campo. Ao mesmo tempo, a disponibilidade das infraestruturas de carregamento ainda é limitada e fornece uma área de aplicação promissora para pesquisa em comunicação e controlo. Esta tese concentra-se no controlo do estado de energia oferecido pelos edifícios/casas fornecendo uma gestão de energia durante a sessão de carregamento de veículo elétrico. Também descreve o desenvolvimento de um sistema para controlar dinamicamente o carregamento dos veículos elétricos para manter a operação do sistema de energia, conhecendo a energia disponível. Para carregar os veículos elétricos, é necessária uma comunicação entre o veículo elétrico e a estação de carregamento. A comunicação é baseada na norma IEC61851, que especifica um sinal de modulação por largura de pulso enviado ao veículo elétrico para definir a corrente de carregamento. O hardware do sistema consiste em dois módulos, uma estação de carregamento e um coordenador ambos com capacidade de comunicação, enquanto os algoritmos de gestão de energia estão num servidor que calcula a energia disponível com base no comportamento do consumo de energia e usa-o para atribuir a carga do veículo elétrico. O sistema tem como objetivo controlar a sessão de carregamento do veículo elétrico, considerando o consumo de energia para controlar a corrente de carregamento. No caso de vários veículos elétricos, o sistema irá gerir a sessão de carregamento com base em um nível de prioridade, priorizando o veículo elétrico que iniciou o primeiro carregamento. Os resultados mostram a viabilidade da abordagem do sistema de carregamento para controlar a estação de carregamento do veículo elétrico, considerando o consumo de energia do sistema e a introdução do nível de prioridade para vários veículos elétricos

Non-intrusive load monitoring of household devices using a hybrid deep learning model through convex hull-based data selection

The availability of smart meters and IoT technology has opened new opportunities, ranging from monitoring electrical energy to extracting various types of information related to household occupancy, and with the frequency of usage of different appliances. Non-intrusive load monitoring (NILM) allows users to disaggregate the usage of each device in the house using the total aggregated power signals collected from a smart meter that is typically installed in the household. It enables the monitoring of domestic appliance use without the need to install individual sensors for each device, thus minimizing electrical system complexities and associated costs. This paper proposes an NILM framework based on low frequency power data using a convex hull data selection approach and hybrid deep learning architecture. It employs a sliding window of aggregated active and reactive powers sampled at 1 Hz. A randomized approximation convex hull data selection approach performs the selection of the most informative vertices of the real convex hull. The hybrid deep learning architecture is composed of two models: a classification model based on a convolutional neural network trained with a regression model based on a bidirectional long-term memory neural network. The results obtained on the test dataset demonstrate the effectiveness of the proposed approach, achieving F1 values ranging from 0.95 to 0.99 for the four devices considered and estimation accuracy values between 0.88 and 0.98. These results compare favorably with the performance of existing approaches.This research was funded by Programa Operacional Portugal 2020 and Operational Program CRESC Algarve 2020, grant numbers 39578/2018 and 72581/2020. Antonio Ruano also acknowledges the support of Fundação para a Ciência e Tecnologia, grant UID/EMS/50022/2020, through IDMEC under LAETAinfo:eu-repo/semantics/publishedVersio

The coproduction of electric mobility: selectivity, conformity and fragmentation in the sociotechnical acceptance of vehicle-to-grid (V2G) standards

In this article we explore how a single standard dealing with vehicle-to-grid (V2G) mobility, ISO 15118, is coproduced in divergent ways across Asia, Europe, and North America. Specifically, ISO 15118 enables V2G as it oversees the communication between electric vehicles (EVs) and electric vehicle service equipment. It allows for bidirectional electricity flows and thereby offers electricity grids the use of EV batteries for grid services like frequency control and demand side management. We observe that highly technical and invisible standards like these are understudied in the energy literature and commonly misinterpreted as purely technical in scope. Hence in our contribution we offer such a study and use ISO 15118 to show how even in the most technical and invisible of cases, politics is still at work. We argue that standards, through a process of coproduction, are of vital importance for the governance of energy systems and play a major role in energy transitions through the various nontechnical assumptions scripted into them. Drawing from a synthesis of the literature on standardization, innovation studies, and science and technology studies, we thus analyse the implementation of ISO 15118 in the United States, China, Denmark and the Netherlands. We find a detailed technical standard that is implemented with differing degrees and in different sociotechnical and institutional contexts. We conclude by suggesting what this selectivity, compliance and fragmentation means for electric mobility and energy policymaking more generally