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Due to the predicted rise of Unmanned Aircraft Systems (UAS) in commercial, civil, and military operations, there is a desire to make UASs more energy efficient so they can proliferate with ease of deployment and maximal life per charge. To address current limitations, a three-tiered approach is investigated to mitigate Unmanned Aerial Vehicle (UAV) hover time, reduce network datalink transmission to a ground station, and provide a real-time framework for Sense-and-Avoidance (SAA) target classification. An energy-efficient UAS architecture framework is presented, and a corresponding SAA prototype is developed using commercial hardware to validate the proposed architecture using an experimental methodology. The proposed architecture utilizes classical computer vision methods within the Detection Subsystem coupled with deeply learned Convolutional Neural Networks (CNN) within the Classification Subsystem. Real-time operations of three frames per second are realized enabling UAV hover time and associated energy consumption during SAA processing to be effectively eliminated. Additional energy improvements are not addressed in the scope of this work. Inference accuracy is improved by 19% over baseline COTS models and current non-adaptive, single-stage SAA architectures. Overall, by pushing SAA processing to the edge of the sensors, network offload transmissions and reductions in processing time and energy consumption are feasible and realistic in future battery-powered electric air transportation systems.

With an increasing awareness of the detrimental effects of the fossil fuel?based transportation sector, which accounts for 14% of human-made greenhousegas emissions globally, individuals, companies, and government entities have made a concerted push to develop solutions to provide modes of transportation that are less carbon intensive. Importantly, several countries, including Norway, India, France, and Britain, have decided to end the sale of internal combustion engine cars in the near future, further accelerating the shift to electric transportation.

With the ever-growing need for lithium-ion batteries, particularly from the electric transportation industry, a large amount of lithium-ion batteries is bound to retire in the near future, thereby leading to serious disposal problems and detrimental impacts on environment and energy conservation. Currently, commercial lithium-ion batteries are composed of transition metal oxides or phosphates, aluminum, copper, graphite, organic electrolytes with harmful lithium salts, polymer separators, and plastic or metallic cases. The lack of proper disposal of spent lithium-ion batteries probably results in grave consequences, such as environmental pollution and waste of resources. Thus, recycling of spent lithium-ion batteries starts to receive attentions in recent years. However, owing to the pursuit of lithium-ion batteries with higher energy density, higher safety and more affordable price, the materials used in lithium-ion batteries are of a wide diversity and ever-evolving, consequently bringing difficulties to the recycling of spent lithium-ion batteries. To address this issue, both technological innovations and the participation of governments are required. This article provides a review of recent advances in recycling technologies of spent lithium-ion batteries, including the development of recycling processes, the products obtained from recycling, and the effects of recycling on environmental burdens. In addition, the remaining challenges and future perspectives are also highlighted.

Radiated electromagnetic emissions from modern electric transportation systems are subject to requirements for their assessment aiming at a general compatibility with radio services. Standards known, recalled and enforced at contractual level narrow to CENELEC EN 50121 (equivalent to IEC 62236) and UMTA 85 and successive integrations. This work synthesizes similarities and differences for the methods and the required system operation, highlighting the areas where improvements are possible and opportune. Correct interpretation of narrowband and broadband phenomena, assignment of sweep time, statistical post processing and evaluation of site/setup uncertainty and repeatability are examples of considered issues that deserve more attention by the railway standardization bodies.

The development of electric vehicles (EVs) has led to an increase in the number of electric vehicle charging stations (EVCSs). However, the lack of proper charging infrastructure can demote the expansion of the electric transportation fleet. In this regard, reducing the impact of EVCS on the distribution networks and choosing optimal charging operations are essential challenges. The optimal placement of an EVCS to minimize the supply cost will encourage the rapid development of the EV transportation system. This paper presents a two-step linear programming (LP) solution for the placement of EVCS with the purpose of optimal operation of an electric vehicle charging station. The charging starting time and charging time interval of each EV are modeled as uncertainty variables. A case study based on a medium-voltage CIGRE distribution network is used to perform simulations and demonstrate the proposed methodology. The numerical analysis is carried out for different charging operation modes based on the standard EV conductive charging systems, IEC 61851.

Great efforts are directed towards the use of electrical vehicles in transportation. Mathematical modeling tools can provide a powerful approach for investigating electrical vehciles and are successfully implemented by applying Matlab/Simulink. In this paper, the mathematical simulation model of Series Excited DC motor (tractive motor) on Matlab/Simulink was implemented and investigated. The main objective of this study is to assess the use of Series Excited DC motor (tractive motor) for the new Amman city express bus project and evaluation of its performance characteristics in different running and loading cases. All simulation results are plotted and discussed. Simulation results showed that Series tractive DC Motor is very suitable in electric (Buses) transport devices. The starting current was about 460 A, (8 times more than the rated motor current) and 357 A in steady state condition with different loads (passengers). This study confirms the feasibility for the use of the series excited DC motor (tractive motor) in electric buses as alternatives for sustaibale and environmentally friendly transportation system.

Automated Electric Transportation (AET) is an innovative concept that aims to integrate energy, vehicle, highway, and communication infrastructures. It provides an electrified transportation system to support in-motion energy transfer through wireless charging of inductive coupling in the highway. A considerable body of previous research has sought to understand and improve the cooperative vehicle and existing infrastructure system. This research is one of the few studies that propose the frameworks that aim to simultaneously deal with both recent advances in vehicle automation and electrified highways to increase overall transportation system performance. The objective of this study is to develop an evaluation framework of the AET system. It focuses on three measures of effectiveness (MOEs): i) the system capacity, ii) energy savings, and iii) environmental emission reduction. They are examined based on simulated vehicle activity profiles. Results are provided to illustrate the performance of the system capabilities. Our results also contribute to an understanding of the key factors that can increase AET performance, and potentially impacts on future transportation mobility and sustainability.

Electric transportation systems have increased in complexity in several ways. For example, electrical performance has increased from what was traditionally the core of the system, a rolling stock and traction supply circuit. Today, a plethora of devices are installed for signaling, communication, and control, requiring a proportionally larger number of interconnecting cables; the reliability and availability of the system has increased, as has user and stakeholder awareness; and system assurance and safety go through a complex and sophisticated process.

El presente artículo propone una metodología para evaluar el impacto de las cargas móviles (trenes eléctricos) del sistema eléctrico del Metro de Quito en la red de la Empresa Eléctrica Quito. Esta metodología, basada en simulación de Montecarlo, permite la generación aleatoria de escenarios de operación de transporte masivo considerando: el desplazamiento, consumo de energía y condiciones de operación de los trenes eléctricos. La propuesta metodológica permite la evaluación probabilística de flujos de potencia mediante funciones de densidad de probabilidad (PDF por sus siglas en inglés); y adicionalmente, propone el cálculo de índices de riesgo para medir, dado un grado de confianza, los mínimos o máximos valores esperados de nivel de carga, voltaje, entre otros factores que caracterizan el nivel de cargabilidad de una red.

This article intends to apply some innovative design methodologies to define, as a first objective, an optimized technical specification and then, as a second objective, to manage the transition from conceptual design to construction project of an innovative means of urban transport, meeting the needs of ‘renewable energy’ requirements, which then declines into an hoverboard. The methodologies used in this manuscript are the quality function deployment (QFD), applied in the first phase of the work to determine what is the appropriate means to move in the centre of medium-large cities; then it is used as a typical method for product marketing, i.e., the decision-making process driven by the analysis of benchmarking, suitable for quantitatively organizing competitive analysis and choosing innovation targets; finally, it is implemented the top-flop analysis in order to better improve the benchmarking implementation, identifying the best product in the market, basing on the highest number of innovative requirements owned by it [1-3].

Neodymium–iron–boron (NdFeB) magnets are used in many applications, from small consumer electronics to future sustainable technologies, e.g., electric transportation and wind power. Rare earth elements (REEs) amount to about a third of the composition of NdFeB magnets. Given that REEs are presently considered critical and have very high supply risk, their recycling from end-of-life products has received increased attention. Magnet-containing streams are valuable secondary sources of REEs, e.g., neodymium, praseodymium, dysprosium, and terbium. This chapter discusses the hydrometallurgical options available for processing NdFeB magnets, whether from end-of-life applications or production residues. The need for recovering REEs from NdFeB materials and the challenges associated with this are addressed. Leaching of magnets and precipitation and solvent extraction of metal ions in the obtained leachates are discussed at length, highlighting the potential and limitations of these methods. Several steps required prior to hydrometallurgical treatment are also described, e.g., dismantling of products and hydrogen decrepitation. A literature review of the available hydrometallurgical processes to treat magnets is presented, focusing on selective and nonselective leaching, selective precipitation, solvent extraction with conventional extractants and ionic liquids, and further refining of products in solution.

Axial Flux Permanent Magnet (AFPM) motors of two types, coreless and conventional topologies, have been studied in order to identify their merits and drawbacks at different ratings, particularly for in-wheel electric transportation applications. The performance of the coreless with several slotpole combinations and number of disks is evaluated. Design of experiments (DOE) methodology is utilized to determine the correlation between input variables and output parameters and the regression models are used to identify the optimum design. Detailed comparison between coreless and conventional topologies at two operating speeds at extreme ends of the driving cycle are conducted.

Recently, more and more countries decided to develop electric vehicles especially electric car. However, because of low prices and other issues, electric bicycles have become the most popular electric transportation vehicles in many developing countries. For example, there are more than 210 million electric bicycles in China. Large-scale electric bicycle charging demand from time to space will not only has an impact on power distribution grid, but also has demand side management (DSM) value. In this paper, we introduced a method for estimating the real-time charging load for electric bicycles. Then we visualized demand in space using heat map and power density node. The numerical results illustrate that large-scale electric bicycle charging demand not only has a great peak-valley but also exhibits unbalance in space.

We consider the coupling introduced between power and transportation systems through Electric Vehicles (EVs). We envision that a number of charging network operators track the mobility of EVs to better estimate their battery charging needs. They use this information to make better-informed decisions on how to participate in the wholesale market of electricity and also to design marginal retail prices that reduce wait times and electricity costs at charging stations. To formulate these decision-making and price design problems, we introduce a network flow model that can capture the temporally-variable travel and charge patterns of an EV population through expanding the transportation network with virtual arcs.

With the growing fleet of a new generation electric vehicles (EVs), it is essential to develop an adequate high power charging infrastructure that can mimic conventional gasoline fuel stations. Therefore, much research attention must be focused on the development of off-board DC fast chargers which can quickly replenish the charge in an EV battery. However, use of the service transformer in the existing fast charging architecture adds to the system cost, size and complicates the installation process while directly connected to medium-voltage (MV) line. With continual improvements in power electronics and magnetics, solid state transformer (SST) technology can be adopted to enhance power density and efficiency of the system. This paper aims to review the current state of the art architectures and challenges of fast charging infrastructure using SST technology while directly connected to the MV line. Finally, this paper discusses technical considerations, challenges and introduces future research possibilities.

Reductions in the carbon intensity of electricity generation, coupled with technological improvements in the end uses that it can power, have created opportunities for the electrification of large segments of the economy. As the largest source of greenhouse gas (GHG) emissions in our economy — 29% of total 2017 U.S. energy-related emissions — electrifying transportation is a key opportunity. Although the technology needed to decarbonize ground transportation exists today, an affordable and reliable transition will require a focus on policy and regulatory changes. Accommodating and correctly managing this growth in electric transportation will be critical to the development of a low-carbon future. If not properly planned for through direct and indirect charging controls, this new load could produce major impacts on the power system and its operations. However, managed correctly, EVs can serve as a useful tool and asset for grid managers and can be accommodated even under aggressive EV adoption models.

Decarbonizing Sweden’s transportation sector is necessary to realize its long-term vision of eliminating net greenhouse gas (GHG) emissions from the energy system by 2050. Within this context, this study develops two scenarios for the transportation sector: one with high electrification (EVS) and the other with high biofuel and biomethane utilization (BIOS). The energy system model STREAM is utilized to compute the socioeconomic system cost and simulate an integrated transportation, electricity, gas, fuel refinery, and heat system. The results show that electrifying a high share of Sweden’s road transportation yields the least systems cost. However, in the least-cost scenario (EVS), bioenergy resources account for 57% of the final energy use in the transportation sector. Further, a sensitivity analysis shows that the costs of different types of cars are the most sensitive parameters in the comparative analysis of the scenarios., International Journal of Sustainable Energy Planning and Management, Vol 14 (2017)

Over the last two decades, motor drives comprising of power electronic converters and advanced electric machines have deeply penetrated into the transportation sector, where new technologies are explored, in order to electrify various modes of transportation systems. Electric transportation puts much greater demand on power electronics than conventional fossil fuel powered automobiles. In many cases (e.g., hybrid internal combustion/electric drive vehicles), optimized power electronics suites are essential. Significant advances in power electronics and motor drives have helped reduce the cost and improve the efficiency of electric vehicles (EVs). This paper reviews on evolution and advancements of permanent magnet synchronous motor (PMSM) drive systems for EVs. The paper also discusses on multiphase PMSMs and multi-motor drive systems which can be revolutionized for future electric transportation applications.

Significant research efforts are underway to develop commercially viable, technically feasible, highly efficient, and highly reliable power converters for renewable energy, electric transportation, and various industrial applications. This chapter presents state-of-the-art knowledge and cutting-edge techniques in various stages of research related to impedance source converters/inverters, including the concepts, advantages compared to existing technology, classification, current status, and future trends. Electric power generation comprises traditional power generation, such as hydroelectric, thermal and nuclear power production, and renewable energy sources, which already has a large penetration joined by photovoltaic (PV) and wind energy. In applications that need to boost the voltage, the Z-source converter is a possibility. Power electronics is the enabling technology for the energy processing necessary for electronic and electrical equipment of all types, from renewable energy to power systems, from house appliances to aerospace systems. New power electronic devices, such as the SiC and GaN, will definitely improve the Z-source converters' performance.

Opting for a multiphase electrical machine may provide, in several industrial cases, significant benefits in terms of performance, resilience and reliability. The interest in multiphase topologies is recently increasing due to the trend for more electric transportation and high power offshore wind turbines. In this paper, the classical analytical method for calculating the slot leakage inductance of three-phase electrical machines with double-layer windings are extended for other multiphase topologies.

In electric transportation there is an inherent need to store electrical energy while maintaining a low vehicle weight. One way to decrease the weight of the structure is to use composite materials ...