Urban and extra-urban hybrid vehicles: a technological review

Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid –electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used

PV Charging and Storage for Electric Vehicles

Electric vehicles are only ‘green’ as long as the source of electricity is ‘green’ as well. At the same time, renewable power production suffers from diurnal and seasonal variations, creating the need for energy storage technology. Moreover, overloading and voltage problems are expected in the distributed network due to the high penetration of distributed generation and increased power demand from the charging of electric vehicles. The energy and mobility transition hence calls for novel technological innovations in the field of sustainable electric mobility powered from renewable energy. This Special Issue focuses on recent advances in technology for PV charging and storage for electric vehicles

Optimizing urban charging infrastructure for shared electric vehicles

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 115-117).This thesis analyses the opportunities and constraints of deploying charging infrastructure for shared electric vehicles in urban environments. Existing electric vehicle charging infrastructure for privately owned vehicles is examined and critiqued. A prototype of smartCharge, an integrated locking, charging, and ambient information system for shared electric vehicles is presented. Design methodology, fabrication of mechanical and electrical systems, and testing of the smartCharge system is documented. Urban implementation case studies for such a universal charging and locking station illustrate the potential of optimized infrastructure for shared vehicles to transform urban streetscapes and improve mobility. An analysis of leveraging existing building electrical infrastructure for vehicle charging is conducted, including phasing strategies for deploying rapid charging. Technological constraints to rapid charging such as battery chemistry, pack design, and power input are presented and evaluated. A strategy for buffering rapid electric vehicle charging with commercial uninterruptible power supply (UPS) systems is described. Two recent buildings on the MIT campus are used as case studies to demonstrate the overhead transformational capacity that exists in many modem, multi-purpose buildings. Connectivity between electrified transport, the electrical grid, and renewable energy sources is explored. A vision for personal urban mobility enabled by fleets of shared electric vehicles powered by clean, renewable energy and intelligent charging infrastructure is proposed.by Praveen Subramani.S.M

An Isolated Integrated Charger for Electric or Plug-in Hybrid Vehicles

For electric and hybrid vehicles using grid power to charge the battery, traction circuit components are not normally engaged during the charging time, so there is a possibility to use them in the charger circuit to have an on-board integrated charger.In this Licentiate thesis, an isolated high power integrated charger is proposed, designed and constructed based on a special ac machine with a double set of stator windings called motor/generator.The charger is capable of unit power factor operation as well as bi-directional power operation for grid to vehicle application.The mathematical electromechanical model of the motor/generator is derived and presented. Based on the developed model, new controller schemes are developed and designed for the grid synchronization and charge control. The machine windings are re-arranged for the traction and charging by a controllable relay-based switching device that is designed for this purpose.A laboratory system is designed and implemented based on a $4$ pole $25~kW$ interior permanent magnet synchronous motor and a frequency converter considering the integrated charging features for winding re-configuration. The practical results will be added in the next step of the project. The charging power is limited to $12.5~kW$ due to the machine thermal limit (half of the motor full power in the traction mode) for this system.The whole system is simulated in Matlab/Simulink based on the developed model and controllers to verify the system operation for the charge control. Simulation results show that the system has good performance during the charging time for a load step change. The simulation results show also a good performance of the controllers leading to machine speed stability and smooth grid synchronization. Moreover, the unit power factor operation is achieved for battery charging in the simulations

An Isolated Integrated Charger for Electric or Plug-in Hybrid Vehicles

For electric and hybrid vehicles using grid power to charge the battery, traction circuit components are not normally engaged during the charging time, so there is a possibility to use them in the charger circuit to have an on-board integrated charger.In this Licentiate thesis, an isolated high power integrated charger is proposed, designed and constructed based on a special ac machine with a double set of stator windings called motor/generator.The charger is capable of unit power factor operation as well as bi-directional power operation for grid to vehicle application.The mathematical electromechanical model of the motor/generator is derived and presented. Based on the developed model, new controller schemes are developed and designed for the grid synchronization and charge control. The machine windings are re-arranged for the traction and charging by a controllable relay-based switching device that is designed for this purpose.A laboratory system is designed and implemented based on a $4$ pole $25~kW$ interior permanent magnet synchronous motor and a frequency converter considering the integrated charging features for winding re-configuration. The practical results will be added in the next step of the project. The charging power is limited to $12.5~kW$ due to the machine thermal limit (half of the motor full power in the traction mode) for this system.The whole system is simulated in Matlab/Simulink based on the developed model and controllers to verify the system operation for the charge control. Simulation results show that the system has good performance during the charging time for a load step change. The simulation results show also a good performance of the controllers leading to machine speed stability and smooth grid synchronization. Moreover, the unit power factor operation is achieved for battery charging in the simulations

Overcoming barriers and increasing independence: service robots for elderly and disabled people

This paper discusses the potential for service robots to overcome barriers and increase independence of elderly and disabled people. It includes a brief overview of the existing uses of service robots by disabled and elderly people and advances in technology which will make new uses possible and provides suggestions for some of these new applications. The paper also considers the design and other conditions to be met for user acceptance. It also discusses the complementarity of assistive service robots and personal assistance and considers the types of applications and users for which service robots are and are not suitable

Improving the Efficiency of Energy Harvesting Embedded System

In the past decade, mobile embedded systems, such as cell phones and tablets have infiltrated and dramatically transformed our life. The computation power, storage capacity and data communication speed of mobile devices have increases tremendously, and they have been used for more critical applications with intensive computation/communication. As a result, the battery lifetime becomes increasingly important and tends to be one of the key considerations for the consumers. Researches have been carried out to improve the efficiency of the lithium ion battery, which is a specific member in the more general Electrical Energy Storage (EES) family and is widely used in mobile systems, as well as the efficiency of other electrical energy storage systems such as supercapacitor, lead acid battery, and nickel–hydrogen battery etc. Previous studies show that hybrid electrical energy storage (HEES), which is a mixture of different EES technologies, gives the best performance. On the other hand, the Energy Harvesting (EH) technique has the potential to solve the problem once and for all by providing green and semi-permanent supply of energy to the embedded systems. However, the harvesting power must submit to the uncertainty of the environment and the variation of the weather. A stable and consistent power supply cannot always be guaranteed. The limited lifetime of the EES system and the unstableness of the EH system can be overcome by combining these two together to an energy harvesting embedded system and making them work cooperatively. In an energy harvesting embedded systems, if the harvested power is sufficient for the workload, extra power can be stored in the EES element; if the harvested power is short, the energy stored in the EES bank can be used to support the load demand. How much energy can be stored in the charging phase and how long the EES bank lifetime will be are affected by many factors including the efficiency of the energy harvesting module, the input/output voltage of the DC-DC converters, the status of the EES elements, and the characteristics of the workload. In this thesis, when the harvesting energy is abundant, our goal is to store as much surplus energy as possible in the EES bank under the variation of the harvesting power and the workload power. We investigate the impact of workload scheduling and Dynamic Voltage and Frequency Scaling (DVFS) of the embedded system on the energy efficiency of the EES bank in the charging phase. We propose a fast heuristic algorithm to minimize the energy overhead on the DC-DC converter while satisfying the timing constraints of the embedded workload and maximizing the energy stored in the HEES system. The proposed algorithm improves the efficiency of charging and discharging in an energy harvesting embedded system. On the other hand, when the harvesting rate is low, workload power consumption is supplied by the EES bank. In this case, we try to minimize the energy consumption on the embedded system to extend its EES bank life. In this thesis, we consider the scenario when workload has uncertainties and is running on a heterogeneous multi-core system. The workload variation is represented by the selection of conditional branches which activate or deactivate a set of instructions belonging to a task. We employ both task scheduling and DVFS techniques for energy optimization. Our scheduling algorithm considers the statistical information of the workload to minimize the mean power consumption of the application while satisfying a hard deadline constraint. The proposed DVFS algorithm has pseudo linear complexity and achieves comparable energy reduction as the solutions found by mathematical programming. Due to its capability of slack reclaiming, our DVFS technique is less sensitive to small change in hardware or workload and works more robustly than other techniques without slack reclaiming

Research and innovation in transport electrification in Europe: An assessment based on the Transport Research and Innovation Monitoring and Information System (TRIMIS)

Electrification has a major role to play in decarbonising transport and in reducing its fossil fuel dependency. For transport electrification to be cost-efficient and ready for future needs, adequate research and innovation (R&I) in this field is necessary. This report provides a comprehensive analysis of R&I in transport electrification. The assessment follows the methodology developed by the European Commission’s Transport Research and Innovation Monitoring and Information System (TRIMIS). The report critically assesses research by thematic area and technologies, highlighting recent developments and future needs.JRC.C.4-Sustainable Transpor

Impacts and solutions on vehicle to grid (V2G) infrastructure.

Masters Degree. University of KwaZulu-Natal, Durban.To deal with the problem of global warming and dependency on oil, the need for emmissionfree transport has brought electric vehicles to life. The main aim of this thesis is to investigate, analyze and propose solutions to the impact of electric vehicles (EVs) on the smart grid. Before investigating the impacts of electric vehicles to smart grid, it is important to have a better understanding of EVs, power grids and vehicle to grid (V2G) infrastructure. The fundamentals of V2G technology are provided in the thesis to understand V2G infrastructure. A power demand study for domestic customers is carried out which asseses the best period for charging electric vehicles at home. Several domestic customer distribution feeders are studied and common observations are drawn. The number of EVs that can be connected to the distribution transformer per phase is calculated and discussed. This calculation considers three home charging levels and types of distribution transformers used by the South African utility company ESKOM together with common observations from demand studies. The electric vehicle is modelled and simulated using MATLAB. The aim of this work is to understand EV power requirements, energy requirements and EV charging times. The electric vehicle is simulated travelling at different road gradients and travelling at different speeds for each road slope. The study results in terms of the impacts of V2G infrastructure are provided and discussed systematically. It is observed that the main impacts include: overloading, under-voltage, imbalance and network instability. Possible solutions to the impacts are provided and discussed. The solutions include overnight charging, constructive charging, balanced charging, distributed controlled charging and centralized controlled charging. After careful analysis, it is observed that the charging impacts are further minimized when these solutions are combined together. Overall results, discussion and conclusion are provided. The challenges faced in this study are outlined and recommendations for future studies are given. In this thesis, it is found that EVs can be safely integrated into a power grid with intelligent charge control through V2G. V2G provides significant benefits to all stakeholders. V2G has many additional applications in the smart grid and microgrids

Federal Register

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii