Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.7
2.9
Journals
Electronics
Special Issues
Emerging Technologies in Wireless Power Transfer Systems
share announcement

Emerging Technologies in Wireless Power Transfer Systems

A special issue of Electronics (ISSN 2079-9292). This special issue belongs to the section "Power Electronics".

Deadline for manuscript submissions: closed (15 July 2022) | Viewed by 9875

Special Issue Editors

Dr. Albert Ting Leung Lee

E-Mail Website
Guest Editor
Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam 999077, Hong Kong
Interests: emerging LED driver technology; sustainable lighting technology; wireless power transfer; advanced single-inductor multiple-output (SIMO) topology; digitally-controlled power converters
Prof. S.Y. (Ron) Hui

E-Mail Website
Guest Editor
Electrical and Electronic Engineering, Nanyang Technological University, Singapore 637458, Singapore
Interests: electric power conversion; planar coreless transformer technology; wireless power transfer; sustainable lighting technology; renewable energy technologies and smart grid technology
Dr. M.H. Bryan Pong

E-Mail Website
Guest Editor
Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam, Hong Kong
Interests: switching power supplies and power electronics
Dr. Gus Cheng Zhang

E-Mail Website
Guest Editor
Department of Electrical and Electronic Engineering, University of Manchester, Oxford Rd, Manchester M13 9PL, UK
Interests: power electronics; wireless power transfer

Special Issue Information

Dear Colleagues,

Wireless power transfer (WPT) has ushered in a new era that will fundamentally change the way we recharge various kinds of electronic devices, including mobile phones, wearables, tablets, Internet-of-Things (IoT) gadgets, medical implants, and even electric vehicles (EVs). A major challenge of modern WPT systems is that the existing wireless charging infrastructure is unable to keep up with the increasing energy and performance demands of a myriad of portable electronic devices. Both researchers and engineers are scrambling to find compact, low-cost, and efficient solutions that will enable rapid, safe, convenient, and simultaneous wireless charging for a greater number of non-identical devices of different power ratings.

The multi-coil approach in wireless power transfer has steadily emerged as an appealing solution for modern WPT applications. The use of multiple coils increases the likelihood that one of the transmitting coils will align well with the receiving coil on the device being charged. It not only significantly improves the freedom of positioning of the receiving device, but also allows the charging of multiple electronic devices simultaneously. However, the main issue of using multiple coils is that it substantially increases the complexity and cost of the wireless power transmitter. Conventional multi-coil wireless transmitter in multi-coil wireless power system (MCWPT) suffer from a high component count, large form factor, low power density, reduced power efficiency and higher cost. Therefore, new circuit topologies are needed for future MCWPT systems, which should capably charge multiple non-identical devices concurrently at higher power ratings while attaining fast and reliable dynamic performances.

For example, new inverters used in a Qi-compliant wireless charger should possess the attributes of being (i) compact, (ii) economical, (iii) highly efficient, (iv) reliable, and (v) scalable to an increasing number of transmitting coils, as well as having a (vi) good dynamic performance, (vii) no cross-coupling, (viii) acceptably low harmonic distortion, (ix) high power rating, and (x) providing each output with an independent and variable voltage, frequency, and power flow.

In addition to powering a mobile device using a unidirectional array of coils, a new approach known as 3D omnidirectional inductive power charging (IPT) has emerged. It allows for 2 free positioning of the mobile devices being charged at any location and in any direction or orientation within a zone. This opens up vast research opportunities for investigating new system architectures and circuit topologies in omnidirectional wireless power systems.

With the rapid proliferation of Internet-of-Things (IoT) and machine-to-machine (M2M) communications, a greater number of sensor nodes are required in order to collect the required information (e.g., light, ambient temperature, image, power consumption, pressure, and gas) and then send them to a master node for IoT services, such as a smart home or smart city. These sensor nodes are often powered from external batteries. Hence, it becomes a major challenge to manage the batteries of each sensing device as the number of these devices increases. Furthermore, the operating lifetime of the sensor devices is short because of the limited battery capacity. In view of this, radio-frequency (RF) wireless power transmission and harvesting emerges as a key technique for powering IoT sensor nodes because of its long distance power transmission (also known as over-the-air wireless charging). Nevertheless, there are a number of outstanding issues that need to be addressed, such as EMF safety, cross-interferences among wireless channels, low sensitivity, and low RF to DC power conversion efficiency.

In summary, this Issue titled “Emerging Technologies in Wireless Power Transfer Systems” is envisaged to have a big impact in both academia and industry because of the rapid proliferation of wireless power technology and the massive demand for a wireless charging infrastructure.

Dr. Albert Ting Leung Lee
Prof. S.Y. (Ron) Hui
Dr. M.H. Bryan Pong
Dr. Gus Cheng Zhang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Electronics is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Wireless power transfer
  • Novel inverter topologies
  • Omni-directional wireless charging
  • Multi-band resonator design
  • Over-the-air wireless charging
  • RF wireless power harvesting
  • Beamforming
  • RF to DC power conversion

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

12 pages, 19861 KiB  
Article
A Design Methodology for Irregularly Shaped Windings in Inductive Wireless Power Transfer Systems
by Cheng Zhang
Electronics 2022, 11(22), 3754; https://doi.org/10.3390/electronics11223754 - 16 Nov 2022
Cited by 1 | Viewed by 1077
Abstract
Inductive wireless power transfer systems often incorporate unconventional, irregularly shaped transmitter windings for the purposes of covering a designated area, fitting into special enclosures and enhancing the tolerance of misalignment. To design and optimise the winding structures, the inductive parameters must be extracted [...] Read more.
Inductive wireless power transfer systems often incorporate unconventional, irregularly shaped transmitter windings for the purposes of covering a designated area, fitting into special enclosures and enhancing the tolerance of misalignment. To design and optimise the winding structures, the inductive parameters must be extracted and linked to the design objectives. Conventionally, these parameters can be extracted using three-dimensional finite element analysis, which often requires subjective manual tweaks and prolonged trial and error procedures. The efficacy is therefore greatly dependent on the experience of the designer. In this paper, a case study for modelling and optimising the spatial coverage by scuplturing the winding shape is demonstrated via a Christmas tree model, utilising the parametric formation equations and line-integral based numerical solvers. A cone-shaped winding with variable interturn pitches was used as the transmitter and a receiver winding was designed to be fit into a bubble that can be hung on the tree. A two-stage optimisation method with simplified degree-of-freedom parameters and brutal force search was used to find the optimal design candidate. Heatmaps of receiver output voltages were generated in a time-efficient way, intuitively helping the designers to make adjustments for the winding structures. A practical prototype was built to verify the open loop voltage distribution on the receiving winding at various positions and another demonstration was made to show the continuum of power coverage around the Christmas tree. Full article
(This article belongs to the Special Issue Emerging Technologies in Wireless Power Transfer Systems)
►▼ Show Figures

Figure 1

15 pages, 4773 KiB  
Article
Using Zone Impedance Matching Technique to Improve the Power Transfer Capability of an Inductive Charging System over a Long Distance
by Jintao Hu, Liangxi He, Heng Liu, Raymond Wai Man Ng and Chi-Kwan Lee
Electronics 2022, 11(13), 1982; https://doi.org/10.3390/electronics11131982 - 24 Jun 2022
Viewed by 1201
Abstract
In many outdoor inductive charging applications, the objects can move quickly, and the environment can change unpredictably. It is therefore difficult to design a fast controller that tracks the change in mutual coupling between the transmitter and receiver. The diminished power delivery to [...] Read more.
In many outdoor inductive charging applications, the objects can move quickly, and the environment can change unpredictably. It is therefore difficult to design a fast controller that tracks the change in mutual coupling between the transmitter and receiver. The diminished power delivery to the objects either leads to incomplete charging or prolongs the charging time. In this paper, the concept of a zone impedance matching technique is proposed. This technique pre-matches the transmitter coil to the desired coupling coefficients. Thus, the power transfer capability of the inductive charger can be maintained at a reasonably high level over a long transmission distance and under a wide receiver misalignment. Based on a three-coil inductive power transfer (IPT) system, the proposed concept is practically implemented with a simple control scheme. The proposed IPT system equips a multi-tap transmitter coil to provide flexibility in selecting different numbers of turns in the transmitter coil. The controller senses the currents of the transmitter coil and the repeater coil to determine the zone of impedance to adapt to the change in mutual coupling of the coils. A mathematical analysis is conducted to formulate the design procedures for the proposed system. Under a wide range of distance and misalignment conditions, practical measurement results verified that the proposed system achieves higher power delivery than an ordinary design. Full article
(This article belongs to the Special Issue Emerging Technologies in Wireless Power Transfer Systems)
►▼ Show Figures

Figure 1

13 pages, 4183 KiB  
Article
Artificial Neural Network-Based Parameter Identification Method for Wireless Power Transfer Systems
by Liangxi He, Sheng Zhao, Xiaoqiang Wang and Chi-Kwan Lee
Electronics 2022, 11(9), 1415; https://doi.org/10.3390/electronics11091415 - 28 Apr 2022
Cited by 10 | Viewed by 1765
Abstract
In this paper, a Wireless Power Transfer (WPT) system parameter identification method that combines an artificial neural network and system modeling is presented. During wireless charging, there are two critical parameters; specifically, mutual inductance and load resistance, which change due to the movement [...] Read more.
In this paper, a Wireless Power Transfer (WPT) system parameter identification method that combines an artificial neural network and system modeling is presented. During wireless charging, there are two critical parameters; specifically, mutual inductance and load resistance, which change due to the movement of the transmitter/receiver and battery conditions. The identification of these two uncertain parameters is an essential prerequisite for the implementation of feedback control. The proposed method utilizes an Artificial Neural Network (ANN) to acquire a mutual inductance value. A succinct system model is formulated to calculate the load resistance of the remote receiver. The maximum error of the mutual inductance estimation is 2.93%, and the maximum error of the load resistance estimation is 7.4%. Compared to traditional methods, the proposed method provides an alternative way to obtain mutual inductance and load resistance using only primary-side information. Experimental results were provided to validate the effectiveness of the proposed method. Full article
(This article belongs to the Special Issue Emerging Technologies in Wireless Power Transfer Systems)
►▼ Show Figures

Figure 1

12 pages, 5183 KiB  
Article
Metal Object Detection in a Wireless High-Power Transfer System Using Phase–Magnitude Variation
by Sunhee Kim, Woong Choi and Yongseok Lim
Electronics 2021, 10(23), 2952; https://doi.org/10.3390/electronics10232952 - 27 Nov 2021
Cited by 6 | Viewed by 1911
Abstract
Recently, wireless charging technologies for large moving objects, such as electric vehicles and robots, have been actively researched. The power transmitting and receiving coils in most large moving objects are structurally separated by a given distance, which exposes a high output power to [...] Read more.
Recently, wireless charging technologies for large moving objects, such as electric vehicles and robots, have been actively researched. The power transmitting and receiving coils in most large moving objects are structurally separated by a given distance, which exposes a high output power to the outside world. If a foreign metal object enters the area between these two coils during wireless power transfer, fire hazards or equipment damage may occur. Therefore, we propose a method for detecting foreign metal objects in the gap between the transmitting and receiving coils in a wireless high-power transfer system. A resonant detection coil set is used to exploit the change induced in electrical characteristics when a foreign metal object is inserted. The mutual inductance of the foreign metal object changes the impedance of the detection coil set. We developed a simple circuit to detect both the magnitude and phase change of the voltage signal according to the altered impedance. Additionally, we implemented a prototype of a wireless power transfer system with a detection system to verify that even small foreign metal objects can be detected effectively. Full article
(This article belongs to the Special Issue Emerging Technologies in Wireless Power Transfer Systems)
►▼ Show Figures

Graphical abstract

16 pages, 6251 KiB  
Article
Stability Improvement of Dynamic EV Wireless Charging System with Receiver-Side Control Considering Coupling Disturbance
by Kaiwen Chen, Ka Wai Eric Cheng, Yun Yang and Jianfei Pan
Electronics 2021, 10(14), 1639; https://doi.org/10.3390/electronics10141639 - 9 Jul 2021
Cited by 12 | Viewed by 2808
Abstract
Receiver-side control has been a reliable practice for regulating the transferred energy to the batteries in the electric vehicle (EV) wireless power transfer (WPT) systems. Nonetheless, the unpredictable fluctuation of the mutual inductance in dynamic wireless charging brings extreme instability to the charging [...] Read more.
Receiver-side control has been a reliable practice for regulating the transferred energy to the batteries in the electric vehicle (EV) wireless power transfer (WPT) systems. Nonetheless, the unpredictable fluctuation of the mutual inductance in dynamic wireless charging brings extreme instability to the charging process. This overshoot that appears in instant vibrations may largely increase the voltage/current stress of the system, and even cause catastrophic failure in the battery load. In addition, the speed of the vehicles may lead to untraceable steady-state operation. However, existing solutions to the above two issues suffer from either long communication time delay or significantly compromised output regulation. In this paper, the slow dynamics and the overshoot issues of the WPT system are elaborated in theory, and the small-signal model mainly considering mutual inductance disturbance is established. A simple feedforward control is proposed for overshoot damping and fast system dynamics. Experimental results validate that the overshoot can be reduced by 13% and the settling time is improved by 50% in vehicle braking or acceleration. In constant speed driving, the battery charging ripple is decreased by 12% and ensures better system stability. Full article
(This article belongs to the Special Issue Emerging Technologies in Wireless Power Transfer Systems)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop