Energy-security-based contactless battery charging system for roadway-powered electric vehicles

This paper proposes an encrypted contactless charging system for roadway-powered electric vehicles (EVs), where the energy can be specifically transferred from the electric supply to authorized EVs. The key of the proposed energy encryption scheme is to utilize the random-like Gaussian map as the security key to chaotically regulate the charging circuit of the electric supply. In such way, the energy can be wirelessly transferred to authorized EVs, while unauthorized EVs cannot illegally acquire the electric energy without knowledge of the security key. Hence, the proposed energy encryption scheme can significantly improve the secure performance of the roadway EV charging system. In this paper, the simulated and experimental results are both provided to illustrate the effectiveness of the proposed the encrypted contactless charging system for multiple roadway-powered EVs. © 2015 IEEE.published_or_final_versio

Wireless Power Transfer Technology for Electric Vehicle Charging

In the years 1884-1889, after Nicola Tesla invented "Tesla Coil", wireless power transfer (WPT) technology is in front of the world. WPT technologies can be categorized into three groups: inductive based WPT, magnetic resonate coupling (MRC) based WPT and electromagnetic radiation based WPT. MRC-WPT is advantageous with respect to its high safety and long transmission distance. Thus it plays an important role in the design of wireless electric vehicle (EV) charging systems. The most significant drawback of all WPT systems is the low efficiency of the energy transferred. Most losses happen during the transfer from coil to coil. This thesis proposes a novel coil design and adaptive hardware to improve power transfer efficiency (PTE) in magnetic resonant coupling WPT and mitigate coil misalignment, a crucial roadblock to the acceptance of WPT for EV. In addition, I do some analysis of multiple segmented transmitters design for dynamic wireless EVs charging and propose an adaptive renewable (wind) energy-powered dynamic wireless charging system for EV

A Review of Dynamic Wireless Power Transfer for In‐Motion Electric Vehicles

Dynamic wireless power transfer system (DWPT) in urban area ensures an uninterrupted power supply for electric vehicles (EVs), extending or even providing an infinite driving range with significantly reduced battery capacity. The underground power supply network also saves more space and hence is important in urban areas. It must be noted that the railways have become an indispensable form of public transportation to reduce pollution and traffic congestion. In recent years, there has been a consistent increase in the number of high‐speed railways in major cities of China, thereby improving accessibility. Wireless power transfer for train is safer and more robust when compared with conductive power transfer through pantograph mounted on the trains. Direct contact is subject to wear and tear; in particular, the average speed of modern trains has been increasing. When the pressure of pantograph is not sufficient, arcs, variations of the current, and even interruption in power supply may occur. This chapter provides a review of the latest research and development of dynamic wireless power transfer for urban EV and electric train (ET). The following key technology issues have been discussed: (1) power rails and pickups, (2) segmentations and power supply schemes, (3) circuit topologies and dynamic impedance matching, (4) control strategies, and (5) electromagnetic interference

Challenges and Barriers of Wireless Charging Technologies for Electric Vehicles

Electric vehicles could be a significant aid in lowering greenhouse gas emissions. Even though extensive study has been done on the features and traits of electric vehicles and the nature of their charging infrastructure, network modeling for electric vehicle manufacturing has been limited and unchanging. The necessity of wireless electric vehicle charging, based on magnetic resonance coupling, drove the primary aims for this review work. Herein, we examined the basic theoretical framework for wireless power transmission systems for EV charging and performed a software-in-the-loop analysis, in addition to carrying out a performance analysis of an EV charging system based on magnetic resonance. This study also covered power pad designs and created workable remedies for the following issues: (i) how power pad positioning affected the function of wireless charging systems and (ii) how to develop strategies to keep power efficiency at its highest level. Moreover, safety features of wireless charging systems, owing to interruption from foreign objects and/or living objects, were analyzed, and solutions were proposed to ensure such systems would operate as safely and optimally as possible

Precise Analysis on Mutual Inductance Variation in DynamicWireless Charging of Electric Vehicle

Wireless power transfer provides an opportunity to charge electric vehicles (EVs) without electrical cables. Two categories of this technique are distinguished: Stationary Wireless Charging (SWC) and DynamicWireless Charging (DWC) systems. Implementation of DWC is more desirable than SWC as it can potentially eliminate challenges associated with heavy weight batteries and time-consuming charging processes. However, power transfer efficiency and range, lateral misalignment of coils as well as implementation cost are issues affecting DWC. These issues need to be addressed through developing coil architectures and topologies as well as operating novel semiconductor switches at higher frequencies. This study presents a small-scale dynamic wireless power transfer system for EV. It specifically concentrates on analyzing the dynamic mutual inductance between the coils due to the misalignment as it has significant influence on the EV charging process, particularly, over the output power and overall efficiency. A simulation study is carried out to explore dynamic mutual inductance profile between the transmitter and receiver coils. Mutual inductance simulation results are then verified through practical measurements on fabricated coils. Integrating the practical results into the model, an EV DWC power transfer simulation is conducted and the relation between dynamic mutual inductance and output power are discussed technically

Inductive Wireless Power Transfer Charging for Electric vehicles - A Review

Considering a future scenario in which a driverless Electric Vehicle (EV) needs an automatic charging system without human intervention. In this regard, there is a requirement for a fully automatable, fast, safe, cost-effective, and reliable charging infrastructure that provides a profitable business model and fast adoption in the electrified transportation systems. These qualities can be comprehended through wireless charging systems. Wireless Power Transfer (WPT) is a futuristic technology with the advantage of flexibility, convenience, safety, and the capability of becoming fully automated. In WPT methods resonant inductive wireless charging has to gain more attention compared to other wireless power transfer methods due to high efficiency and easy maintenance. This literature presents a review of the status of Resonant Inductive Wireless Power Transfer Charging technology also highlighting the present status and its future of the wireless EV market. First, the paper delivers a brief history throw lights on wireless charging methods, highlighting the pros and cons. Then, the paper aids a comparative review of different type’s inductive pads, rails, and compensations technologies done so far. The static and dynamic charging techniques and their characteristics are also illustrated. The role and importance of power electronics and converter types used in various applications are discussed. The batteries and their management systems as well as various problems involved in WPT are also addressed. Different trades like cyber security economic effects, health and safety, foreign object detection, and the effect and impact on the distribution grid are explored. Prospects and challenges involved in wireless charging systems are also highlighting in this work. We believe that this work could help further the research and development of WPT systems.publishedVersio

Secondary-Side Control in Dynamic Wireless Power Transfer Systems for Double-Sided Inductor-Capacitor-Capacitor and Series-Series Compensation Topologies

Electric Vehicles (EVs) are fast becoming a great alternative as future mode of transportation, due to their promise of low emissions. Nevertheless, EVs suffer from battery related problems such as large size, heavy weight, high price, long charging times and a short driving range. Dynamic wireless power transfer systems (DWPTSs) address the battery issue by providing power to the vehicle while in motion, and eliminate the need of plugging. However, unavoidable load and coupling coefficient variations cause degradation of power delivery and efficiency. Hence, a controller must be added to the dynamic charger for power conditioning and efficiency enhancement. This project is focused on the control stage of the DWPTS adopting a post-regulation scheme as control strategy. It proposes the integration of a secondary-side-only control under double-sided inductor-capacitor-capacitor (LCC) and series-series compensation topologies. A synchronous buck converter is used to step down the voltage to the maximum power transfer efficiency (MPTE) conditions and control the direct current (DC) link by adjusting the duty cycle of the control pulse. Averaged alternating current (AC) modelling is applied for designing the controller to smooth and speed the response of both systems. An estimation equation for coupling coefficient and a controller for the double-sided LCC compensation topology are introduced. A comparison study between these two topologies comprised of their characteristics and response to the controller is carried out

Wireless Power Transfer for High-precision Position Detection of Railroad Vehicles

Detection of vehicle position is critical for successful operation of intelligent transportation system. In case of railroad transportation systems, position information of railroad vehicles can be detected by GPS, track circuits, and so on. In this paper, position detection based on tags onto sleepers of the track is investigated. Position information stored in the tags is read by a reader placed at the bottom of running railroad vehicle. Due to limited capacity of battery or its alternative in the tags, power required for transmission of position information to the reader is harvested by the tags from the power wirelessly transferred from the reader. Basic mechanism in wireless power transfer is magnetic induction and power transfer efficiency according to the relative location of the reader to a tag is discussed with simulation results. Since power transfer efficiency is significantly affected by the ferromagnetic material (steel) at the bottom of the railroad vehicle and the track, magnetic beam shaping by ferrite material is carried out. With the ferrite material for magnetic beam shaping, degradation of power transfer efficiency due to the steel is substantially reduced. Based on the experimental results, successful wireless power transfer to the tag coil is possible when transmitted power from the reader coil is close to a few watts.Comment: 2015 IEEE Power, Communication and Information Technology Conference (PCITC) accepted, preprinte

Quantitative analysis of mutual inductances for optimal wireless power transfer via magnetic resonant coupling

This journal issue contains selected papers from the 2014 IEEE International Magnetics (INTERMAG) ConferenceAP - Power and Control Magnetics Ipublished_or_final_versio

Energy harvesting technologies and devices from vehicular transit and natural sources on roads for a sustainable transport: state-of-the-art analysis and commercial solutions

The roads we travel daily are exposed to several energy sources (mechanical load, solar radiation, heat, air movement, etc.), which can be exploited to make common systems and apparatus for roadways (i.e., lighting, video surveillance, and traffic monitoring systems) energetically autonomous. For decades, research groups have developed many technologies able to scavenge energy from the said sources related to roadways: electromagnetism, piezoelectric and triboelectric harvesters for the cars’ stress and vibrations, photovoltaic modules for sunlight, thermoelectric solutions and pyroelectric materials for heat and wind turbines optimized for low-speed winds, such as the ones produced by moving vehicles. Thus, this paper explores the existing technologies for scavenging energy from sources available on roadways, both natural and related to vehicular transit. At first, to contextualize them within the application scenario, the available energy sources and transduction mechanisms were identified and described, arguing the main requirements that must be considered for developing harvesters applicable on roadways. Afterward, an overview of energy harvesting solutions presented in the scientific literature to recover energy from roadways is introduced, classifying them according to the transduction method (i.e., piezoelectric, triboelectric, electromagnetic, photovoltaic, etc.) and proposed system architecture. Later, a survey of commercial systems available on the market for scavenging energy from roadways is introduced, focusing on their architecture, performance, and installation methods. Lastly, comparative analyses are offered for each device category (i.e., scientific works and commercial products), providing insights to identify the most promising solutions and technologies for developing future self-sustainable smart roads