1,732 research outputs found
Improved Design of Wireless Electrical Energy Transfer System for Various Power Applications
This thesis introduces a state-of-the-art review of existing wireless power transfer (WPT) technologies with a detailed comparison and presents the limitations of the inductive power transfer system through simulation and practical analyses. This thesis also presents the expanded use of the high-frequency analysis tool, known as FEKO, and the novel application of frequency response analyser (FRA) with various simulations and practical demonstrations for enhancing the design and maintenance of WPT systems
Insights into dynamic tuning of magnetic-resonant wireless power transfer receivers based on switch-mode gyrators
Magnetic-resonant wireless power transfer (WPT) has become a reliable contactless source of power for a wide range of applications. WPT spans different power levels ranging from low-power implantable devices up to high-power electric vehicles (EV) battery charging. The transmission range and efficiency of WPT have been reasonably enhanced by resonating the transmitter and receiver coils at a common frequency. Nevertheless, matching between resonance in the transmitter and receiver is quite cumbersome, particularly in single-transmitter multi-receiver systems. The resonance frequency in transmitter and receiver tank circuits has to be perfectly matched, otherwise power transfer capability is greatly degraded. This paper discusses the mistuning effect of parallel-compensated receivers, and thereof a novel dynamic frequency tuning method and related circuit topology and control is proposed and characterized in the system application. The proposed method is based on the concept of switch-mode gyrator emulating variable lossless inductors oriented to enable self-tunability in WPT receiversPeer ReviewedPostprint (published version
Magneto-inductive Passive Relaying in Arbitrarily Arranged Networks
We consider a wireless sensor network that uses inductive near-field coupling
for wireless powering or communication, or for both. The severely limited range
of an inductively coupled source-destination pair can be improved using
resonant relay devices, which are purely passive in nature. Utilization of such
magneto-inductive relays has only been studied for regular network topologies,
allowing simplified assumptions on the mutual antenna couplings. In this work
we present an analysis of magneto-inductive passive relaying in arbitrarily
arranged networks. We find that the resulting channel has characteristics
similar to multipath fading: the channel power gain is governed by a
non-coherent sum of phasors, resulting in increased frequency selectivity. We
propose and study two strategies to increase the channel power gain of random
relay networks: i) deactivation of individual relays by open-circuit switching
and ii) frequency tuning. The presented results show that both methods improve
the utilization of available passive relays, leading to reliable and
significant performance gains.Comment: 6 pages, 9 figures. To be presented at the IEEE International
Conference on Communications (ICC), Paris, France, May 201
Near-Field Analysis and Design of Inductively-Coupled Wireless Power Transfer System in FEKO
Inductively-coupled wireless power transfer
(WPT) system is broadly adopted for charging batteries
of mobile devices and electric vehicles. The performance
of the WPT system is sensitively dependent on the
strength of electromagnetic coupling between the coils,
compensating topologies, loads and airgap variation.
This paper aims to present a comprehensive characteristic
analysis for the design of the WPT system with a
numerical simulation tool. The electromagnetic field
solver FEKO is mainly used for studying high-frequency
devices. However, the computational tool is also
applicable for not only the analysis of the electromagnetic
characteristic but also the identification of the electrical
parameters in the WPT system operating in the nearfield. In this paper, the self and mutual inductance of the
wireless transfer windings over the various airgaps were
inferred from the simulated S-parameter. Then, the
formation of the magnetic coupling and the distribution
of the magnetic fields between the coils in the seriesparallel model were examined through the near-field
analysis for recognizing the efficient performance of the
WPT system. Lastly, it was clarified that the FEKO
simulation results showed good agreement with the
practical measurements. When the input voltage of 10 V
was supplied into the transmitting unit of the prototype,
the power of 5.31 W is delivered with the transferring
efficiency of 97.79% in FEKO. The actual measurements
indicated 95.68% transferring efficiency. The electrical
parameters; in , out, in , , in , and out, had a fair
agreement with the FEKO results, and they are under
8.4% of error
Design Elliptic Lowpass Filter with Inductively Compensated Parallel-Coupled Lines
AbstractThis paper presents a simple technique to design an ellicptic transfer fuction microstrip lowpass filter based on a ection of doubly inductive compensated parallel-coupled lines. The proposed lowpass filter has the suppression performance to suppress the signal transmission in transition and stopband better than the filter based on the conventional coupled lines. The proposed design procedures are convenient with the closed form design equation. To emonstrate the techniques performance, simulated and measured results at 0.9GHz cut off frequency LPF with ncompensated and the compensated structures are compared. The measured results obtained from the proposed LPF exhibit 0.2dB insertions, less than 20dB return loss and more suppression performance than 35dB at 1.8GHz
A novel coupler design and analysis with shielding material tests for a CPT system of electric vehicles based on electromagnetic resonant coupling
In this paper, a contactless power transfer (CPT) system using a novel geometrically enhanced energy transfer coupler with three different shielding materials has been built and analysed, along with the evaluations from aspects of electromagnetics and RMS power transmitting based on electromagnetic resonant coupling. A CPT system design improvement with the proposed H-shape ferromagnetic cores and the combined semi-enclosed passive electromagnetic shielding methods have been investigated in terms of generated electromagnetic field characteristics, system power transfer ratings, system efficiency optimization and performances of shielding materials. The results have shown that, across the range of operating frequency of the CPT system, aluminium shielding as a metallic material method could deliver better overall CPT system performance than other two ferromagnetic materials, steel 1010 and ferrite. In addition, the coupler prototype design limitations, misalignment tolerance and the passive shielding design considerations including distance between windings and inner surfaces of shielding shells have been discussed
Wireless Power Transfer
Wireless power transfer techniques have been gaining researchers' and industry attention due to the increasing number of battery-powered devices, such as mobile computers, mobile phones, smart devices, intelligent sensors, mainly as a way to replace the standard cable charging, but also for powering battery-less equipment. The storage capacity of batteries is an extremely important element of how a device can be used. If we talk about battery-powered electronic equipment, the autonomy is one factor that may be essential in choosing a device or another, making the solution of remote powering very attractive. A distinction has to be made between the two forms of wireless power transmission, as seen in terms of how the transmitted energy is used at the receiving point: - Transmission of information or data, when it is essential for an amount of energy to reach the receiver to restore the transmitted information; - Transmission of electric energy in the form of electromagnetic field, when the energy transfer efficiency is essential, the power being used to energize the receiving equipment. The second form of energy transfer is the subject of this book
Pregled stanja u području bezkontaktnog prijenosa električne energije: primjene, izazovi i trendovi
Methods of contactless electrical power transfer technologies have been surveyed and results are presented here. In this among, the inductive based contactless electrical power transfer systems are investigated in more detail. The principles, structures and operations of the systems as well as their methods presented in the literature are reviewed and their applications are explored. Also, current challenges and opportunities and future trends are noted. An effective index is proposed to compare different contactless power transfer systems describing their present statuses and the future trends. Finally, some remarks and recommendations regarding future studies are proposed.U radu je dan prikaz različitih tehnologija u području bezkontaktnog prijenosa električne energije. U radu je naglasak na indukcijom baziranim sustavima bezkontaktnog prijenosa električne energije. Pregledom literature utvrðeni su koncepti, strukture i način rada pojedinih sustava bezkonaktnog prijenosa kao i njihove primjene. Također, zabilježeni su trenutni izazovi, prilike i trendovi. Predložen je efektivni indeks za vrednovanje sustava bezkontaktnog prijenosa električne energije s ciljem komparativne analize različitih sustava opisanih trenutnim statusom i trendovima. Konačno, dan je kritički osvrt i predložene su preporuke za buduće studije
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
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