Roadway-Embedded Transmitters and Multi-Pad Receivers for High Power Dynamic Wireless Power Transfer

Electric vehicles (EVs) offer considerable economic and environmental benefits to society. Despite the decreasing vehicle costs and increasing range of newer EVs, the problem of range anxiety still exists. Range anxiety, at its core, is an issue of charging speeds rather than a concern about the driving range. Dynamic wireless charging of EVs is seen as a potential solution to this issue of range anxiety. Further, wireless charging technology also helps the push towards level 5 autonomy and opens new opportunities for how an EV can be utilized. Dynamic wireless power transfer (DWPT) systems typically require a high initial investment due to the scale of deployment needed and require a certain level of EV adoption before they become economically viable. The challenges facing DWPT technologies are broadly categorized into development, deployment and operation challenges. To address the deployment challenges, this dissertation presents the pavement integration of DWPT systems, and the design and validation of concrete-embedded wireless charging pads. To improve infrastructure utilization and address the operation challenge, different vehicle classes need to recharge from the same charging infrastructure. This is made possible by the use of multi-pad receivers, which allow different vehicle classes to receive different power levels using the same charging infrastructure. This work presents a scaled-down version of a multi-pad receiver system to demonstrate the operation and scalability of these modular receivers. To help further reduce the cost of development and implementation of DWPT systems, finite element method (FEM) and circuit simulation models are presented. The time-domain simulations can be used to develop and validate various control and communication schemes without the need for expensive hardware implementation. Finally, leakage magnetic field reduction to ensure safety and compliance for DWPT systems is discussed, and an example system is analyzed using FEM simulations

Design and optimization of a three phase inductive power transfer system

193 p.El concepto de transporte sostenible dentro de las ciudades debe ser reconsiderado para poder así tener áreas urbanas más saludables. Es un hecho bien conocido que en las grandes ciudades sufren de grandes problemas de contaminación. Principalmente, debido los vehículos de combustión interna, con grandes emisiones de CO2. Estos representan más del 50% de los vehículos utilizados diariamente. Es por ello que el transporte público debe ser estimulado. Particularmente hablando, el transporte ferroviario es muy atractivo, ya que no se producen emisiones directas.Los sistemas de transporte ferroviario, como los tranvías y los metros, son muy ventajosos en términos de eficiencia, precio del usuario, seguridad y comodidad. Sin embargo, en comparación con un vehículo de combustión interna, los costos iniciales y de mantenimiento son muy altos. El alto costo inicial se debe principalmente al alto precio de las baterías. Por otro lado, el mantenimiento se ve enormemente afectado por la corrosión y la exposición ambiental que sufre parte del sistema de alimentación, el pantógrafo y las catenarias, siendo estos los componentes más críticos. Además, en las grandes ciudades, con muchas líneas de tranvía, las catenarias tienen un gran impacto visual. Para solucionar estos problemas, una de las opciones más prometedoras es dotar al vehículo ferroviario de un sistema de transferencia inductiva (IPT). De esta forma, la catenaria podría eliminarse y la carga se realizará de forma inalámbrica con las bobinas del transmisor enterradas en el suelo.Entre los diferentes sistemas posibles de IPT, este trabajo se centra en los sistemas de transferencia de energía inductiva dinámica (DIPT), es decir, cuando se está cargando mientras el vehículo se está moviendo. En concreto, esta tesis se adentra en el diseño de bobinas tipo meandro. El objetivo de este trabajo es proponer un método para diseñar sistemas de carga inductiva trifásicos. Para ello, los principios fundamentales de funcionamiento del sistema IPT se introducen en la primera parte de esta tesis. Las ecuaciones se presentan y se calcula el límite de división de polos. Validándolos en un prototipo de 3.3kW.Posteriormente, se describen los principios de trabajo de la bobina del tipo meandro. Se muestran las ecuaciones que modelan estas bobinas y se resalta la posibilidad de lograr un acoplamiento constante con múltiples fases. Además, con las modificaciones presentadas, el sistema multifásico se puede modelar mediante un sistema monofásico equivalente. Gracias a esto, el límite de división de polos se puede calcular fácilmente. Utilizando este límite, se describe un procedimiento de diseño y se valida experimentalmente en un prototipo de 50W. Este prototipo muestra el potencial de este tipo de bobinas, logrando una transmisión de potencia constante con una eficiencia del 70%.Sobre la base de este procedimiento de diseño, se propone una metodología de optimización para mejorar el tamaño, el peso y el costo del DIPT. Se resaltan los compromisos existentes entre estos indicadores. Finalmente, esta optimización se aplica para un sistema de 9kWy se valida en un banco de prueba real, con una eficiencia medida del 90%, para cualquier posición y potencia de salida con una separación de bobina de 100m

An empirical survey on wireless inductive power pad and resonant magnetic field coupling for in-motion EV charging system

EVs are the recent emerging automotive technology in the transportation sector to reduce the CO2 emission from the internal combustion engine. The issues in EVs technology development are battery tube capacity, heavy-size batteries, fast charging, and safe charging infrastructure. The dynamic wireless charging technology shows a suitable alternative to address the charging system-related issues in EV. However, a limited number of review studies are conducted to specifically address the wireless charging pad design challenges. The wireless inductive power pad and magnetic coupling circuit design are the main factors to decide the performance of the DWPT system. This review analyzes the current developments and challenges associated with wireless charging pad design. Further, this study investigates the potential parameters which improve the performance of a DWPT system to increase the distance traveled (mileage). First, this paper discusses WRIPT technology for DWPT EV charging application, and several parameters affecting the PTE are examined. Also, the aids factors considered for designing the DWPT power pad and different magnetic resonance coupling topologies are presented. In addition, the performance evaluation of the WRIPT power pad, with in-motion testing from the major findings in earlier studies is discussed. Finally, the challenges and opportunities of the WRIPT power pad for in-motion EV charging applications are also addressed. The current state of the art of DWPT and its future directions to make DWPT EV charging systems a full-fledged method are highlighted.Web of Science114693466

Design and optimization of a three phase inductive power transfer system

193 p.El concepto de transporte sostenible dentro de las ciudades debe ser reconsiderado para poder así tener áreas urbanas más saludables. Es un hecho bien conocido que en las grandes ciudades sufren de grandes problemas de contaminación. Principalmente, debido los vehículos de combustión interna, con grandes emisiones de CO2. Estos representan más del 50% de los vehículos utilizados diariamente. Es por ello que el transporte público debe ser estimulado. Particularmente hablando, el transporte ferroviario es muy atractivo, ya que no se producen emisiones directas.Los sistemas de transporte ferroviario, como los tranvías y los metros, son muy ventajosos en términos de eficiencia, precio del usuario, seguridad y comodidad. Sin embargo, en comparación con un vehículo de combustión interna, los costos iniciales y de mantenimiento son muy altos. El alto costo inicial se debe principalmente al alto precio de las baterías. Por otro lado, el mantenimiento se ve enormemente afectado por la corrosión y la exposición ambiental que sufre parte del sistema de alimentación, el pantógrafo y las catenarias, siendo estos los componentes más críticos. Además, en las grandes ciudades, con muchas líneas de tranvía, las catenarias tienen un gran impacto visual. Para solucionar estos problemas, una de las opciones más prometedoras es dotar al vehículo ferroviario de un sistema de transferencia inductiva (IPT). De esta forma, la catenaria podría eliminarse y la carga se realizará de forma inalámbrica con las bobinas del transmisor enterradas en el suelo.Entre los diferentes sistemas posibles de IPT, este trabajo se centra en los sistemas de transferencia de energía inductiva dinámica (DIPT), es decir, cuando se está cargando mientras el vehículo se está moviendo. En concreto, esta tesis se adentra en el diseño de bobinas tipo meandro. El objetivo de este trabajo es proponer un método para diseñar sistemas de carga inductiva trifásicos. Para ello, los principios fundamentales de funcionamiento del sistema IPT se introducen en la primera parte de esta tesis. Las ecuaciones se presentan y se calcula el límite de división de polos. Validándolos en un prototipo de 3.3kW.Posteriormente, se describen los principios de trabajo de la bobina del tipo meandro. Se muestran las ecuaciones que modelan estas bobinas y se resalta la posibilidad de lograr un acoplamiento constante con múltiples fases. Además, con las modificaciones presentadas, el sistema multifásico se puede modelar mediante un sistema monofásico equivalente. Gracias a esto, el límite de división de polos se puede calcular fácilmente. Utilizando este límite, se describe un procedimiento de diseño y se valida experimentalmente en un prototipo de 50W. Este prototipo muestra el potencial de este tipo de bobinas, logrando una transmisión de potencia constante con una eficiencia del 70%.Sobre la base de este procedimiento de diseño, se propone una metodología de optimización para mejorar el tamaño, el peso y el costo del DIPT. Se resaltan los compromisos existentes entre estos indicadores. Finalmente, esta optimización se aplica para un sistema de 9kWy se valida en un banco de prueba real, con una eficiencia medida del 90%, para cualquier posición y potencia de salida con una separación de bobina de 100m

Communication‐less Synchronous Rectification for In Motion Wireless Charging

This thesis puts forward a control scheme to allow for synchronous rectification for dynamic wireless power transfer. The automotive industry is transitioning away from internal combustion engines (ICEs) and towards electric vehicles (EVs). This transition is spurred by the environmental and economic benefits EVs offer over ICEs. However, further improvements can still be made to how electric vehicles operate. One of these improvements is the technology of in motion wireless charging or dynamic wireless power transfer. In motion wireless charging offers the ability to remove existing range anxiety concerns for EVs. It also offers the potential for a reduction in battery sizes for EVs, which are the primary cost of EVs, this in turn decreases the total costs of mass EV adoption. Traditional implementations of in motion wireless charging utilize passive rectification to simplify controls between embedded primary pads and the vehicle. However, this solution while effective, limits the potential benefits of wireless charging. The use of synchronous or active rectification techniques, offer improved performance, control techniques, and bidirectional capabilities. However, the reason synchronous rectification is not already used in in motion charging is the complexity of synchronization over wireless communication. To move past this challenge, this thesis investigates a synchronization scheme that can be achieved without communication by taking advantage of induced free resonant currents in the vehicle’s tuning network to synchronize the switching transitions to receive power. In this thesis a traditional in motion wireless charging system utilizing passive rectification is designed and built as a benchmark for dynamic charging. Simulations of this control scheme are presented. Practical considerations are addressed for hardware realization. Finally, the control approach is validated through hardware in static and dynamic applications

Innovation in Energy Systems

It has been a little over a century since the inception of interconnected networks and little has changed in the way that they are operated. Demand-supply balance methods, protection schemes, business models for electric power companies, and future development considerations have remained the same until very recently. Distributed generators, storage devices, and electric vehicles have become widespread and disrupted century-old bulk generation - bulk transmission operation. Distribution networks are no longer passive networks and now contribute to power generation. Old billing and energy trading schemes cannot accommodate this change and need revision. Furthermore, bidirectional power flow is an unprecedented phenomenon in distribution networks and traditional protection schemes require a thorough fix for proper operation. This book aims to cover new technologies, methods, and approaches developed to meet the needs of this changing field

Design optimization of contactless power transfer systems for electric vehicles using electromagnetic resonant coupling

Contactless power transfer (CPT) systems have been gaining considerable attention and have achieved tremendous technology advancements across a wide variety of utilizations in the past decade. CPT technologies offer promising advantages and open up new avenues for development of numerous real-world applications. Of particular importance is the implementation of CPT systems on the charging of electric vehicles (EV), which are considered as a sustainable alternative that will effectively address global fossil energy scarcity and climate change issues in the future. The overarching aim of this thesis is to investigate and improve the operation performance of CPT systems for contactless EV charging. Optimized high-performance CPT systems are expected to be the ultimate goal for EV wireless charging in the following century. In the CPT applications, some certain characteristic outputs and parameters such as overall system efficiency, RMS power transfer, air gap and resonant frequency are considered as key performance metrics to be addressed. These crucial metrics and properties have been emphasized throughout this thesis. The electromagnetic resonant coupling technique has been put forward and adopted for most designed prototypes in this thesis in order to optimize the overall performance of CPT systems. The research methodology development, model designs, implementations and results analysis of the thesis are undertaken from the perspective of both power electronics and electromagnetics towards achieving the main objectives of the research. With focuses on overall system efficiency, real transfer power to load, air gap, frequency, magnetic coupler design, shielding materials, inner shielding distance and misalignment characteristics, a range of studies have been conducted in the thesis based on the proposed methodology, enhanced simulation models and laboratory prototypes. A number of important contributions have been made by the thesis. The four most significant contributions are: Firstly, the originally developed methodology for the CPT research of the thesis – the research flowchart system based on the preliminary natural resonant frequency probe and anticipation method. This uniquely proposed method for this thesis has been used to effectively probe, track and narrow down the most appropriate resonant frequency range to be chosen for CPT systems to perform with, towards reaching an optimized status of electromagnetic resonant coupling in terms of CPT technology-based EV charging. Secondly, the magnetic coupler modular-based CPT designs for investigating overall system performance optimization. As a result, in the thesis, a novel small-sized CPT prototype that is based on a geometrically improved H-shaped magnetic coupler, with ferromagnetic cores, passive aluminium shielding, an SS compensation topology and electromagnetic resonant coupling, has been proposed as an optimal design solution. Thirdly, approximating a CPT system to operate in close proximity to its calculated natural resonant frequency point by tuning and controlling system operating frequency could effectively lead to an overall system performance optimization most of the time in practical applications using electromagnetic resonant coupling, whereas setting the system operating frequency exactly at its calculated natural resonant frequency to make the system maximally operate at an extreme state of magnetic resonance may only produce a partial optimization from perspective of the system parameters and outputs. Fourthly, reasonable trade-offs between performance metrics are required to be considered and evaluated in order to achieve a feasible overall CPT system optimization. Through the detailed analysis of the results, model outcome comparisons, explanations on findings, limitation discussions and holistic system evaluations, this thesis is devoted to report and provide a series of newly proposed solutions and innovatively designed CPT systems. These solutions are supported by empirical findings, conclusions and contributions, which may encourage further pursuits of system performance optimizations for high-power high-frequency CPT charging technologies applied for future EV, despite methodological limitations, experiment restrictions and external uncertainties

Innovation in Energy Systems

It has been a little over a century since the inception of interconnected networks and little has changed in the way that they are operated. Demand-supply balance methods, protection schemes, business models for electric power companies, and future development considerations have remained the same until very recently. Distributed generators, storage devices, and electric vehicles have become widespread and disrupted century-old bulk generation - bulk transmission operation. Distribution networks are no longer passive networks and now contribute to power generation. Old billing and energy trading schemes cannot accommodate this change and need revision. Furthermore, bidirectional power flow is an unprecedented phenomenon in distribution networks and traditional protection schemes require a thorough fix for proper operation. This book aims to cover new technologies, methods, and approaches developed to meet the needs of this changing field