Magnetic resonant coupling (MRC) is an efficient method for realizing the near-field wireless power transfer (WPT). Although the MRC enabled WPT (MRC-WPT) with a single pair of transmitter and receiver has been thoroughly studied in the literature, there is limited work on the general setup with multiple transmitters and/or receivers. In this paper, we consider a point-to-multipoint MRC-WPT system with one transmitter delivering wireless power to a set of distributed receivers. We aim to introduce new applications of signal processing and optimization techniques to the performance characterization and optimization in multiuser WPT via MRC. We first derive closed-form expressions for the power drawn from the energy source at the transmitter and that delivered to the load at each receiver. We identify a "near-far" fairness issue in multiuser power transmission due to receivers' distance-dependent mutual inductance with the transmitter. To tackle this issue, we propose a centralized charging control algorithm to jointly optimize the receivers' load resistance to minimize the total transmitter power drawn while meeting the given power requirement of each individual load. For ease of practical implementation, we also devise a distributed algorithm for the receivers to adjust their load resistance independently in an iterative manner. Last, we characterize the power region that constitutes all the achievable power-tuples of the loads via controlling their adjustable resistance. In particular, we compare the power regions without versus with the time sharing of users' power transmission, where it is shown that time sharing yields a larger power region in general. Extensive simulation results are provided to validate our analysis and corroborate our study on the multiuser MRC-WPT system.
Wireless charging technology provides a solution to the insufficient battery life of electric vehicles (EVs). However, the conflict of interests between wireless charging lanes (WCLs) and EVs is difficult to resolve. In the day-ahead electricity market, considering the revenue of WCLs caused by the deviation between actual electricity sales and pre-purchased electricity, as well as endurance and traveling experience of EVs, this paper proposes a charging scheduling algorithm based on a double-layer game model. In lower layer, the potential game is used to model the multi-vehicle game of vehicl…
Objective Aiming at the problems of many interference factors in the electromagnetic radiation simulation of electric vehicles, a field measurement scheme for charging devices is designed. Through the monitoring of wireless charging equipment, the radiation level and distribution of the electric field value and magnetic field value around the charging equipment is explored, to analyze the influence law of the electromagnetic environment. Method This paper introduces the principle and development status of electric vehicle charging, and analyzes the classification and methods of wireless chargi…
Wireless charging coupled with computation offloading in edge networks offers a promising solution for realizing power-hungry and computation intensive applications on user devices. We consider a mutil-access edge computing (MEC) system with collocated MEC servers and base-stations/access points (BS/AP) supporting multiple users requesting data computation and wireless charging. We propose an integrated solution with computation offloading to satisfy the largest proportion of requested wireless charging while keeping the energy consumption at the minimum subject to the MEC-AP transmit power an…
With the increasing popularity of the Internet of Things(IoT) devices, the demand for fast and convenient battery charging services grows rapidly. Wireless charging is a promising technology for such a purpose and its usage has become ubiquitous. However, the close distance between the charger and the device being charged not only makes proximity-based and near field communication attacks possible, but also introduces a new type of vulnerabilities. In this paper, we propose to create fingerprints for wireless chargers based on the intrinsic non-linear distortion effects of the underlying charg…
Distributed laser charging (DLC) is a wireless power transfer technology for mobile electronics. Similar to traditional wireless charging systems, the DLC system can only provide constant power to charge a battery. However, Li-ion battery needs dynamic input current and voltage, thus power, in order to optimize battery charging performance. Therefore, neither power transmission efficiency nor battery charging performance can be optimized by the DLC system. We at first propose an adaptive DLC (ADLC) system to optimize wireless power transfer efficiency and battery charging performance. Then, we…
This paper investigates the problem of bidirectional energy exchange between electric vehicles (EVs) and road lanes embedded with wireless power transfer technologies called wireless charging-discharging lanes (WCDLs). As such, EVs could provide better services to the grid, especially for balancing the supply-demand, while bringing convenience for EV users, because no cables and EV stops are needed. To enable this EV--WCDL energy exchange, a novel decentralized peer-to-peer (P2P) trading mechanism is proposed, in which EVs directly negotiate with a WCDL to reach consensus on the energy price a…
Route Optimization of Electric Vehicles based on Dynamic Wireless Charging
University of Thessaly（色萨利大学）；De Montfort University（德蒙福特大学）；Nottingham Trent University（诺丁汉特伦特大学）；University of Surrey（萨里大学）；T.E.I. of Thessaly（色萨利技术教育学院）
This paper analyzes the energy efficiency of a novel system model where unmanned aerial vehicles (UAVs) are used to provide coverage for user hotspots (user clusters) and are deployed on charging pads to enhance the flight time. We introduce a new notion of "cluster pairs" to capture the dynamic nature of the users' spatial distribution in order to exploit one of the top advantages of UAVs, which is the mobility and relocation flexibility. Using tools from stochastic geometry, we first derive a new distance distribution that is vital for energy efficiency analysis. Next, we compute the coverag…
While the fifth-generation cellular (5G) is meant to deliver Gigabit peak data speeds, low latency, and connect to billions of devices, and 6G is already on the way, half of the world population living in rural areas are still facing challenges connecting to the internet. Compared with urban areas, users in rural areas are greatly impacted by low income, high cost of backhaul connectivity, limited resources, extreme weather, and natural geographical limitations. Hereby, how to connect the rural areas and what are the difficulties of providing connectivity draw great attention. This article fir…
This paper presents the design, implementation and evaluation of In-N-Out, a software-hardware solution for far-field wireless power transfer. In-N-Out can continuously charge a medical implant residing in deep tissues at near-optimal beamforming power, even when the implant moves around inside the human body. To accomplish this, we exploit the unique energy ball pattern of distributed antenna array and devise a backscatter-assisted beamforming algorithm that can concentrate RF energy on a tiny spot surrounding the medical implant. Meanwhile, the power levels on other body parts stay in low le…
