Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Magnetically Coupled Resonance Wireless Power Transfer Mr Wpt With Multiple Self Resonators PDF full book. Access full book title Magnetically Coupled Resonance Wireless Power Transfer Mr Wpt With Multiple Self Resonators.
| Author | : Youngjin Park |
| Publisher | : |
| Total Pages | : |
| Release | : 2012 |
| Genre | : |
| ISBN | : 9789533078748 |
| Author | : Yiming Zhang |
| Publisher | : Springer |
| Total Pages | : 130 |
| Release | : 2017-12-21 |
| Genre | : Technology & Engineering |
| ISBN | : 9811065381 |
This thesis focuses on the key technologies involved in magnetically coupled Wireless Power Transfer (WPT). Starting from the basic structures and theories of WPT, it addresses four fundamental aspects of these systems. Firstly, it analyzes the factors affecting transfer efficiency and compares various methods for reducing the working frequency. Secondly, it discusses frequency splitting and offers a physical explanation. Thirdly, it proposes and assesses three multiple-load transfer structures. Lastly, it investigates WPT systems with active voltage-source and current-source load. As such, the thesis offers readers a deeper understanding of WPT technology, while also proposing insightful new advances.
| Author | : Ali Agcal |
| Publisher | : |
| Total Pages | : |
| Release | : 2016 |
| Genre | : Technology |
| ISBN | : |
In this chapter, a wireless power transmission system based on magnetic resonance coupling circuit was carried out. Mathematical expressions of optimal coupling coefficients were examined with the coupling model. Equivalent circuit parameters were calculated with Maxwell 3D software, and then, the equivalent circuit was solved using MATLAB technical computing software. The transfer efficiency of the system was derived using the electrical parameters of the equivalent circuit. System efficiency was analyzed depending on the different air gap values for various characteristic impedances using PSIM circuit simulation software. Since magnetic resonance coupling involves creating a resonance and transferring the power without the radiation of electromagnetic waves, resonance frequency is a key parameter in system design. The aim of this research was to define the efficiency according to variations of coefficients in wireless power transfer (WPT) system. In order to do that, the calculation procedure of mutual inductance between two self-resonators is performed by Maxwell software. Equivalent circuit is solved in circuit simulator PSIM platform. The calculations show that using the parameters that are obtained by magnetic analysis can be used for the equivalent circuit which has the capability to provide the efficiency using electrical quantities. The chapter discusses the application of this approach to a coil excited by a sinusoidal voltage source and a receiver coil, which receives energy voltage and current. Both could be obtained to calculate the instantaneous power and efficiency. To do so, the waveforms for voltage and current were obtained and computed with the PSIM circuit simulator. As the air gap between the coils increased, the coupling between the coils was weakened. The impedance of the circuit varied as the air gap changed, affecting the power transfer efficiency. In order to determine the differences between the software programs, efficiency values were calculated using three kinds of software. And it is concluded that equivalent circuit analysis by means of numerical computing is proper to obtain the voltage and current waveforms. Correspondingly, transmission efficiency can be calculated using the electrical relations.
| Author | : Wan Peng |
| Publisher | : |
| Total Pages | : 0 |
| Release | : 2018 |
| Genre | : |
| ISBN | : |
The widespread use of all kinds of small portable devices have created the demands for wireless power transfer (WPT) systems that are proper for mobile devices. In this thesis, magnetically coupled resonance (MCR) WPT systems are developed with innovative design techniques. Specifically, two MCR-WPT systems are proposed: one is symmetric while another is asymmetric. The symmetric system has a small transmitter of the same size as the receiver of 32×32×3.91 mm. The optimal charging distance is 35 mm with the maximum transfer efficiency of 32.8%. The asymmetric system has a large transmitter of 200×200×1.6 mm and the receiver size remains small. The maximum transfer efficiency is 51.8% and the optimal charging distance is 60 mm. The proposed systems are simulated using the finite element method, and then fabricated and tested. The results demonstrate that the proposed systems can enable wireless power charging of small electronics with acceptable efficiency.
| Author | : Sherif Hekal |
| Publisher | : Springer |
| Total Pages | : 91 |
| Release | : 2019-05-29 |
| Genre | : Technology & Engineering |
| ISBN | : 9811380473 |
This book addresses the design challenges in near-field wireless power transfer (WPT) systems, such as high efficiency, compact size, and long transmission range. It presents new low-profile designs for the TX/RX structures using different shapes of defected ground structures (DGS) like (H, semi-H, and spiral-strips DGS). Most near-field WPT systems depend on magnetic resonant coupling (MRC) using 3-D wire loops or helical antennas, which are often bulky. This, in turn, poses technical difficulties in their application in small electronic devices and biomedical implants. To obtain compact structures, printed spiral coils (PSCs) have recently emerged as a candidate for low-profile WPT systems. However, most of the MRC WPT systems that use PSCs have limitations in the maximum achievable efficiency due to the feeding method. Inductive feeding constrains the geometric dimensions of the main transmitting (TX)/receiving (RX) resonators, which do not achieve the maximum achievable unloaded quality factor. This book will be of interest to researchers and professionals working on WPT-related problems.
| Author | : Zhigang Dang |
| Publisher | : |
| Total Pages | : 72 |
| Release | : 2013 |
| Genre | : Electronic dissertations |
| ISBN | : |
Wireless power transfer (WPT) technology has many potential applications such as consumer electronics and electric vehicles (EV). High transmission efficiency with long transmission distance and with large lateral misalignment is desired in WPT systems. Magnetic resonance coupled (MRC) WPT systems are suitable for midrange high efficiency wireless power transfer (WPT). In chapter 2, commonly used four-loop and two-loop MRC-WPT system configurations are analyzed and compared in terms of transmission efficiency and transmission distance first based on the simplified circuit model. An example symmetrical system simulation shows that with the same Tx, Rx, source and load, the four-loop system has longer transmission distance but with relatively lower transmission efficiency compare to the two-loop system. Then, A 3-D physical model of 5-turn, 400mm outer diameter spiral shape four-loop WPT system is developed and simulated by using ANSYS® HFSS® software package. Operation distance of 550mm with nearly constant maximum transmission efficiency of 92.3% is achieved. Laterally misaligned MRC-WPT system is investigated in chapter 3. The TEVD, a region on the transmission efficiency versus Rx lateral misalignment amount curve where the transmission efficiency first sharply drops from high efficiency down to zero and then recovers to a low efficiency value, is identified in this work. The identification of TEVD is verified by simulation results obtained from a developed ANSYS® HFSS® 3-D physical model. Simulation results of the ANSYS® HFSS® 3-D physical model with 5-turn, 60cm outer diameter spiral shape MRC-WPT system show that when the Rx is 30cm vertically away from the Tx, TEVD exists when the lateral misalignment value ranges from 50cm to 70cm. An elimination method for TEVD is proposed in chapter 4. The proposed method utilizes angular rotation of the Rx (or Tx) to eliminate the zero-coupling point which causes the TEVD and boosts the coupling coefficient such that the TEVD is eliminated and the high efficiency region is extended. ANSYS® HFSS® 3-D physical model simulation results show that the proposed method eliminates the TEVD and extends the high efficiency region from 50cm lateral misalignment (83.3% of the Rx diameter) to 70cm lateral misalignment (117% of the Rx diameter). Chapter 5 summarizes the thesis conclusions and sheds the light on future work.
| Author | : Mohamed Zellagui |
| Publisher | : BoD – Books on Demand |
| Total Pages | : 176 |
| Release | : 2021-08-18 |
| Genre | : Technology & Engineering |
| ISBN | : 1839688017 |
Wireless power transfer (WPT) is a promising technology used to transfer electric energy from a transmitter to a receiver wirelessly without wires through various methods and technologies using time-varying electric, magnetic, or electromagnetic fields. It is an attractive solution for many industrial applications due to its many benefits over wired connections. This book discusses the theory and practical aspects of WPT technology.
| Author | : Cheng Zhang |
| Publisher | : Open Dissertation Press |
| Total Pages | : 184 |
| Release | : 2017-01-26 |
| Genre | : Technology & Engineering |
| ISBN | : 9781361042915 |
This dissertation, "Directional and Omnidirectional Inductively Coupled Wireless Power Transfer Systems" by Cheng, Zhang, 張騁, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: This thesis presents the analysis and design methods of directional and omnidirectional inductively coupled wireless power transfer systems. Such system utilizes multiple coils to generate high frequency alternating magnetic fields in space and allows receivers to pick up power wirelessly in any position. The objective of optimization is to achieve the maximum power efficiency. Such kind of system allows the mobile devices to be continuously charged without staying on a fixed place. Self- and mutual- inductance values of the coils are critical parameters that affect the power efficiency of a wireless power transfer system. An improved numerical calculation method is proposed and is presented in this thesis. It combines the theory of partial equivalent element circuit (PEEC) and empirical equations for calculating certain types of straight conductors. The segmentation method to discretize the conductor is optimized and verified. The accuracy of the proposed method has been tested and compared to both theoretical equations and measurements of practical coils, and is proved to be accurate. The time-varying magnetic fields induced by the coils in a wireless power transfer system is the \transporter" of the energy. A time-efficient visualization method is proposed and is presented in this thesis. While commercial finite element analysis (FEA) software such as ANSYS Maxwell can perform transient analysis, the execution time is extremely long as the accuracy greatly depends on the simulation time steps and the number of iterations. The proposed method calculates the time-instant currents in coils with the derived mathematic model and then directly plots the time-varying magnetic fields. The execution time is shortened to a few of minutes on a desktop computer while the FEA solver takes a couple of hours on the same model. Several types of multiple-coil systems are analyzed with their magnetic field patterns. To transmit power to arbitrary directions, the magnetic field must be controlled with its directions. According to the principle of superposition, a three-orthogonal-coil transmitter structure is proposed. Several current control methods are discussed to achieve omnidirectional wireless power characteristics. One is a continuous scanning type current scheme. The receivers placed in the designated area can receive power with any locations and angles. Another one is a discrete scanning type. It can be used to detect the load position and therefore delivering power to the load with the maximum power efficiency of the overall system. Simulations and experiments have been carried out to verify the theory and they agreed well. While the aforesaid omnidirectional system adopts the special three-orthogonal-coil structure, the theory is generalized to arbitrary numbers of transmitters. It is proved by mathematical derivation that in a system with multiple transmitters and single receiver, there exists an optimal efficiency point when currents in the transmitter coils fulfill the certain relationships, regardless of the compensation scheme of the circuit, the use of magnetic materials and the shapes of the coils. An implementable method to calculate the optimal currents in a practical multiple-transmitter-single-receiver system is also provided. The generalized theory is verified by both simulations and experiments. Subjects: Electric power transmission
| Author | : Xingyi Shi |
| Publisher | : |
| Total Pages | : 138 |
| Release | : 2019 |
| Genre | : |
| ISBN | : |
Emerging wireless charging technologies will become essential for medical implants, which currently require cables passing through patients' skin in order to provide power, or force the patient to undergo costly surgery operations to replace dead batteries. Likewise, makers of sensors and devices used on the factory floor are increasingly looking towards wireless power to eliminate the need for battery changes and eliminate downtime. Even the ever-increasing number and diversity of consumer electronics, such as smartphones, laptops, wearables, and VR headsets, will benefit from wireless power solutions that make battery charging more convenient. Commercially available wireless chargers, such as those implementing the Qi standard, partially address the problem. Qi chargers can typically charge only one device at a time and require precise alignment of transmitter and receiver, and so are not effective as the number of electronics that need to be charged increases. Magnetic resonance wireless power transfer systems, which use resonant coils as transmitters, have greater range and tolerance to misalignment. However, the size of the transmitter cannot be arbitrarily increased to fit any large area because large transmitter-to-receiver size ratios result in extreme inefficiency. As an enhancement on magnetic resonance, phased array transmitters explored in academic research can extend transmission range. However, they have the tradeoff of increased cost and complexity, because each array element requires an independent RF source. Non-magnetic methods of wireless power transfer, such as radiative ultra-high frequency beaming and tracking laser systems, have more extended power transfer range but much less efficiency, and they both have lower output power limits due to safety regulations. So whereas these methods may be useful for devices that only need small amount of energy and require long separation distances, they cannot be used for systems that require high power output while still being safe for use near humans and animals. This dissertation focuses on the design of a wireless power transfer solution that can provide efficient wireless charging over a large area, can tolerate some amount of separation and misalignment, can charge multiple devices at the same time, at a reasonable complexity and cost, and can do all of this while staying well within safety regulations. To achieve this, we introduce an adaptive, passive wireless relay system to extend power transfer range. A prototype of a centrally controlled array of reconfigurable relays (CARR) is implemented that can deliver power to multiple moving receivers. We show that the relay system is much more efficient at delivering power to small receivers over a large area than a single transmitter system, and has better uniformity of coverage. The CARR prototype can identify and adaptively route power to a new or moving receiver in as little as 120 microseconds. Additionally, a method for enabling large area power transfer without a large transmitter is introduced, which proposes to use receivers themselves as relays when many receivers are in close proximity. We demonstrate a key step towards realizing this receivers-as-relay system by showing that a suitable routing configuration for delivering power to receivers can be identified using a load modulation technique. Finally, in evaluating the safety of magnetic resonance systems, we conclude an interesting feature of coupled resonator systems which reduces safety concerns by reducing the SAR, a measure of the energy absorbed by biological tissue.
| Author | : Basem M. Badr |
| Publisher | : |
| Total Pages | : |
| Release | : 2016 |
| Genre | : |
| ISBN | : |
Rodents are essential models for research on fundamental neurological processing and for testing of therapeutic manipulations including drug efficacy studies. Telemetry acquisition from rodents is important in biomedical research and requires a long-term powering method. A wireless power transfer (WPT) scheme is desirable to power the telemetric devices for rodents. This dissertation investigates a WPT system to deliver power from a stationary source (primary coil) to a moving telemetric device (secondary coil) via magnetic resonant coupling. The continuously changing orientation of the rodent leads to coupling loss/problems between the primary and secondary coils, presenting a major challenge. We designed a novel secondary circuit employing ferrite rods placed at specific locations and orientations within the coil. The simulation and experimental results show a significant increase of power transfer using our ferrite arrangement, with improved coupling at most orientations. The use of a medium-ferrite-angled (4MFA) configuration further improved power transfer. Initially, we designed a piezoelectric-based device to harvest the kinetic energy available from the natural movement of the rodent; however, the harvested power was insufficient to power the telemetric devices for the rodents. After designing our 4MFA device, we designed a novel wireless measurement system (WMS) to collect real-time performance data from the secondary circuit while testing WPT systems. This prevents the measurement errors associated with voltage/current probes or coaxial cables placed directly into the primary magnetic field. The maximum total efficiency of our novel WPT is 14.1% when the orientation of the 4MFA is parallel to the primary electromagnetic field, and a current of 2.0 A (peak-to-peak) is applied to the primary coil. We design a novel controllable WPT system to facilitate the use of multiple secondary circuits (telemetric devices) to operate within a single primary coil. Each telemetric device can tune or detune its resonant frequency independently of the others using its internal control algorithm.
