Wireless Charging: Its types, Standards and Applications

An electrical gadget can be powered without cords by providing electrical via an air pocket to the device in order to re-charge its capacity. The performance and practicality of cordless charging tech have noticeably enhanced lately. The introduction to cordless charging in this paper covers its basics. The evaluation of standards, which includes Qi and the A4WP, is then given, as well as a focus on their communications channels. Next, we put out a cutting-edge idea for cordless charger networking, which enables chargers to be linked for easier data gathering and management. We explain how the wireless charger network can be used to assign users to chargers, which demonstrates the usefulness in terms of a reduction costs for users to find the best chargers to recharge their mobile devices

Boost Battery

In modern times, the problem of a depleted battery confronts us too often. Whether it appears with a smartphone or with any other electronic device, the situation frustrates all consumers. This project designs and constructs a compact portable battery charger that charges through kinetic energy. Thus, one can perform everyday activities, such as walking or running, and charge up a backup battery with no extra effort or time. Additionally, an attachable band harvests thermal energy to maximize the amount of clean power generated. Energy harvesting from kinetic motion and thermal differences provide users with power when no actual power suppliers are nearby; a crucial advantage especially for emergency situations. So much of the energy we expend throughout our day escapes into the environment. As renewable energy becomes more necessary in today’s culture, Boost provides an option for those trying to cut back on electricity costs or those trying to reduce their carbon footprint. Now, with this power bank, the heat and movement of your body directly charge your phone or personal electronic device. The user can even harness the energy of their pet by attaching it to their dog or cat if they do not feel up for running any further

Inductive wireless power transmission for automotive applications

Technology has revolutionised all aspects of human life at all consecutive intervals and Fourth Industrial Revolution is no different. Daily transport and energy industries not only shape the future of a country’s economy, but also make the economy highly yielding due to recent advances. Electric vehicles (EV) have been rapidly invading the market share during recent years. The advancements in EV and enhanced market share demand EV charging, being more reliant on either conventional plug-in charging or wireless charging. Given the limitations within battery related apparatus such as escalating battery costs, higher weight and lower power density, wireless power transfer (WPT) is a novel state of the art technology in energising. WPT has remarkable characteristics such as enhanced flexibility, mobility, convenience and safety, indicating potential benefits, if it is adopted for EV with similar efficiency; for example, it can eliminate the use of charging cables. Despite the fact that the wireless charges for EV, have undergone significant development phase during the last decade, many design limitations are yet to be addressed. Although the technology has been commercially outgrown, key limitations such as limited efficiency over distance, limited driving range, vulnerability to misalignments, or positional offsets are yet to be researched. Moreover, although high system efficiency can be attained, the distance variations between the transmitter and receiver and the misalignments will impact the system efficiency. This thesis addresses the aforementioned limitations and design challenges of the magnetic resonance WPT system, and proposes a novel transmitter and receiver circuit and coil designs, to minimise the impact of distance variations and coil misplacement, reduce the size and improve charging performance. This thesis focusses on inductive wireless power transfer (IWPT) which is also referred to as magnetic resonance and reviews and contrasts other WPT mechanisms. Additionally, it presents a detailed mathematical analysis of inductive wireless power circuit model to obtain accurate modelling parameters. Two and four loop strongly coupled magnetic resonance (SCMR) wireless power systems have been mathematically analysed and their performance has been evaluated. A novel combined, conformal strongly coupled magnetic resonance system (CSCMR) has been combined with SCMR, in order to minimise the dimensions of the receiver and compensate the coupling factor due to distance variations between the transmitter and receiver. In the second phase, additional inductors were added to the existing loosely coupled system to obtain higher efficiencies over higher distances. The size of the system has significantly reduced due to the additional smaller transmitter and receiver inductor which were added to the existing system to achieve better performance. The validity of each design has been discussed via a set of simulations, and their measurements have been obtained via prototypes. Finally, a smart WPT charging system, consisting of six transmitter loops and a sensor network array, for an autonomous parking space was developed. The proposed method reduces the energy required for determining a car’s location, eventually increasing the performance of the charger

Revving up for the future: an inductive power transfer system geared for vehicular applications

Energized by the prospect of decluttering the charging infrastructure by severing the bulky power cords used to charge an Electric Vehicle (EV), an innovative technique to wirelessly charge an EV battery known as Inductive Power Transfer (IPT) has garnered widespread acceptance. This thesis introduces the design of an integrated stationary IPT system with an optimized power control algorithm and efficiency maximization to transfer power from a transmitter pad positioned on the ground and the receiver pad embedded under the chassis of an EV. Magnetic analysis for the charging coil architecture is facilitated via simulations in Ansys Maxwell. The power electronics design focuses on implementation of an H-bridge converter incorporating Series-Series (SS) compensation topology to utilize a novel control algorithm to prioritize battery charging operation. The system is validated through a simulation model in PSIM and a hardware-in-the-loop simulation in Typhoon HIL before hardware implementation and testing of the developed prototype

PowerShake: power transfer interactions for mobile devices

Current devices have limited battery life, typically lasting less than one day. This can lead to situations where critical tasks, such as making an emergency phone call, are not possible. Other devices, supporting different functionality, may have sufficient battery life to enable this task. We present PowerShake; an exploration of power as a shareable commodity between mobile (and wearable) devices. PowerShake enables users to control the balance of power levels in their own devices (intra-personal transactions) and to trade power with others (inter-personal transactions) according to their ongoing usage requirements. This paper demonstrates Wireless Power Transfer (WPT) between mobile devices. PowerShake is: simple to perform on-the-go; supports ongoing/continuous tasks (transferring at ~3.1W); fits in a small form factor; and is compliant with electromagnetic safety guidelines while providing charging efficiency similar to other standards (48.2% vs. 51.2% in Qi). Based on our proposed technical implementation, we run a series of workshops to derive candidate designs for PowerShake enabled devices and interactions, and to bring to light the social implications of power as a tradable asset

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

Ambient RF energy harvesting and efficient DC-load inductive power transfer

This thesis analyses in detail the technology required for wireless power transfer via radio frequency (RF) ambient energy harvesting and an inductive power transfer system (IPT). Radio frequency harvesting circuits have been demonstrated for more than fifty years, but only a few have been able to harvest energy from freely available ambient (i.e. non-dedicated) RF sources. To explore the potential for ambient RF energy harvesting, a city-wide RF spectral survey was undertaken in London. Using the results from this survey, various harvesters were designed to cover four frequency bands from the largest RF contributors within the ultra-high frequency (0.3 to 3 GHz) part of the frequency spectrum. Prototypes were designed, fabricated and tested for each band and proved that approximately half of the London Underground stations were found to be suitable locations for harvesting ambient RF energy using the prototypes. Inductive Power Transfer systems for transmitting tens to hundreds of watts have been reported for almost a decade. Most of the work has concentrated on the optimization of the link efficiency and have not taken into account the efficiency of the driver and rectifier. Class-E amplifiers and rectifiers have been identified as ideal drivers for IPT applications, but their power handling capability at tens of MHz has been a crucial limiting factor, since the load and inductor characteristics are set by the requirements of the resonant inductive system. The frequency limitation of the driver restricts the unloaded Q-factor of the coils and thus the link efficiency. The system presented in this work alleviates the use of heavy and expensive field-shaping techniques by presenting an efficient IPT system capable of transmitting energy with high dc-to-load efficiencies at 6 MHz across a distance of 30 cm.Open Acces

A design technique for geometric optimisation of resonant coil sizes in low to mid frequency inductive power transmission systems.

Wireless power transfer (WPT) is a well-established method of energising electrically-powered devices. Among the different available WPT techniques, Resonant Inductive Power Transfer (RIPT) has been adapted for use in a wide range of applications. The primary reason is the relatively higher Power Transfer Efficiency (PTE) that RIPT can provide. RIPT systems operate on the principle of magnetic resonance coupling between a Transmitter (Tx) and a Receiver (Rx) coil. Maximising the PTE is a key driver for improving the performance of RIPT systems. In a RIPT link the PTE is influenced by three factors: (i) inductive linkage between the Tx and Rx, (ii) terminating circuitry of Tx and Rx sides and (iii) the Tx/Rx coil's geometrical size. In considering these impacting factors, different techniques to improve PTE have been extensively presented in the literature and are comprehensively reviewed in this thesis. The research work undertaken focuses on the geometrical optimisation of Tx/Rx coils to help maximise PTE in RIPT systems for operation over low- and mid-frequency bands (i.e. between few kHz to several MHz). Conventional methods for maximising PTE require defining various design parameters (i.e. figure-of-merits), which assist in finding the optimum Air-Cored Coil (ACC) geometry. However, traditional techniques for working with Figure-of-Merit (FoM) parameters are very time-consuming and process-demanding. In this thesis, the number of required FoMs have been reduced to one and incorporated into a process that will accelerate production of the optimum geometry design. A unique FoM parameter (i.e. Pscf) is developed by consolidating the PTE's impacting factors. Considering the RIPT application and its physical size constraints, a proper selection method for identifying the numerical value of Pscf is investigated. A novel iterative algorithm has been developed to assist in selection of the most favourable Pscf value, which provides the optimum ACC geometry. Theoretical design examples of two RIPT systems - operating at 10 kHz (low-frequency band) and 300 kHz (mid-frequency band) - are used to investigate the functionality of the ACC design approach, for which successful results are achieved. The novel iterative algorithm is also experimentally validated by developing four prototyped Tx/Rx ACC pairs, with real-world applications, which operate over low- and mid-frequency bands: 1:06 MHz, 100 kHz, 50 kHz, 15 kHz. For the designed ACC geometries, maximum PTEs of 85:63% at 1:06 MHz, 83:10% at 100 kHz, 72:85% at 50 kHz and 34:57% at 15 kHz are practically measured in bench top tests. The measured PTE values are in close correlation (within 14%) with the calculated PTEs at these frequency ranges, and thus validate the novel ACC design procedure. The RIPT system's maximum achievable PTE can be further increased by adding ferrite cores to the Tx/Rx ACC pair. In this thesis, an advanced iterative algorithm is also presented to support the design of geometrically optimised coil pairs employing ferrite cores. The advanced iterative algorithm is an extension of the initial work on optimising ACC geometries. Optimum Ferrite-Cored Coil (FCC) geometries, produced using the advanced iterative algorithm, for RIPT systems operating at 10 kHz and 300 kHz have been investigated. In comparing the FCC and ACC geometries designed for these frequencies, it is demonstrated that RIPT systems with ferrite cores reduce the ACC's geometrical size and additionally improve PTE. To validate the performance of the advanced FCC design algorithm over low- and mid-frequency bands, two RIPT systems are physically constructed for operation at 15 kHz (low-frequency) and 50 kHz (mid-frequency). For the prototyped RIPT systems, maximum PTEs of 45:16% at 50 kHz and 50:74% at 15 kHz are practically measured. The calculated and physically measured PTE values are within 2% difference; hence validating the advanced FCC design process

Advanced Radio Frequency Identification Design and Applications

Radio Frequency Identification (RFID) is a modern wireless data transmission and reception technique for applications including automatic identification, asset tracking and security surveillance. This book focuses on the advances in RFID tag antenna and ASIC design, novel chipless RFID tag design, security protocol enhancements along with some novel applications of RFID

Underwater Optical Wireless Communications Link for Short-Range Data Transmission: A Proof of Concept Study

Gemstone Team OPTICThe purpose of this thesis is to lay the groundwork for the development of a cost-effective Underwater Optical Wireless Communications system. Currently, one of the largest barriers to the expansion of underwater enterprise and research is a lack of high-speed wireless communication systems. Wireless communication underwater is essential for safety, improving aquatic technology, and many other marine ventures, yet it is still technologically limited. Current methods, such as acoustic communication, are often power inefficient, cumbersome, and expensive. The proposed system would enable scuba divers and researchers to bridge the technological gaps in available underwater data transmission systems. This paper proposes using visible light to wirelessly transmit data underwater. Visible light is an effective carrier wave underwater due to its large bandwidth and low absorption coefficient. Using light emitting diodes, silicon PIN photodetectors, waterproof enclosures, and consumer-grade microcontrollers, a model for the development of a wireless optical communications system is proposed. The system also adopts a modular design which allows each component to evolve as needed. The proposed system can transmit and receive audio and vitals signals underwater, illustrating the potential of a technology that could make diving and other underwater endeavors safer and more efficient. Furthermore, the proposed data link shows the potential for this technology to be used in other underwater applications that were previously limited by data speeds or mobility. Above all, this technology seeks to build upon existing knowledge of optical wireless communication and advance the field of underwater science and technology