Wireless Power Research Articles

PET-PZT Dielectric Polarization: Electricity Harvested from Photon Energy

The effect of residual stress or heat on ferroelectrics used to convert photons into electricity was investigated. The data analysis reveals that when the PET-PZT piezoelectric transducer is UV-irradiated with a 405 nm wavelength, it becomes a photon–heat–stress electric energy converter and capacitator. Our objective was to evaluate the PET-PZT photon–heat–stress electric energy conversion performance and the role of the light’s wavelength and intensity. Converting waste energy from energy-intensive processes and systems is crucial to reducing the environmental impact and achieving net-zero emissions. To achieve these, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer.

Experimental investigation on dynamic wireless charging system for electric vehicles using different shape coils

ABSTRACT A dynamic wireless power transfer (DWPT) charging system is a technology that enables the wireless transfer of electrical energy from a power source to a device or vehicle that needs to be charged. The present study aims to investigate the effect of different coil shapes and a number of coil turns on the performance of the DWPT charging system. An experimental investigation was carried out with different types of coil shapes, such as circular, pentagon, square, rhombus, triangle, and hexagon coils. The voltage, efficiency, and charging capacity were measured with different coil shapes for different distances and number of turns. Experimental results showed that as the number of turns increases in the coils, the voltage increases moderately for all the shapes of the coils. From the experimental analysis observed that, at 16 turns of the coil, the circular coil showed higher voltage (15.03 volts) than the other coil shapes. As the number of coils increases, the voltage increases for all the test coils. From the test analysis, it was observed that number of turns and coil shapes had a significant impact on the voltage output, efficiency and charging capacity.

Fluid Flow-Based Vibration Energy Harvesters: A Critical Review of State-of-the-Art Technologies

Energy harvesting technology plays an important role in converting ambient energy into useful electrical energy to power wireless sensing and system monitoring, especially for systems operating in isolated, abandoned or embedded locations where battery replacement or recharging is not a feasible solution. This paper provides an integrative study of the methodologies and technologies of energy harvesting from fluid flow-induced vibration (FIV). The recent research endeavors contributing to flow-based energy harvesting have been reviewed to present the state-of-the-art issues and challenges. Several mechanisms on FIVs including vortex-induced vibrations (VIVs), flutter, galloping and wake galloping are thoroughly discussed in terms of device architecture, operating principles, energy transduction, voltage production and power generation. Additionally, advantages and disadvantages of each FIV energy harvesting mechanism are also talked about. Power enhancement methods, such as induced nonlinearities, optimized harvester’s configuration, hybridization and coupling of aerodynamic instabilities, for boosting the harvester’s output are also elucidated and categorized. Moreover, rotary wind energy harvesters are reviewed and discussed. Finally, the challenges and potential directions related to the flow-based energy harvesters (FBEHs) are also mentioned to provide an insight to researchers on the development of sustainable energy solutions for remote wireless sensing and monitoring systems.

Self-healing Micro-Supercapacitor Based on Robust Liquid Metal-CNT-PEDOT:PSS Film for Wireless Powering of Integrated Strain Sensor.

The limited energy density of micro-supercapacitors (MSCs) and challenges in their integration significantly impede the advancement of MSCs in wearable electronic devices. Here, this work designs a robust and wrinkled liquid metal-CNT-PEDOT:PSS film with high capacity and self-healing properties (defined as LM-CNT-PEDOT:PSS). The wrinkled structure further enhances tensile properties of LM-CNT-PEDOT:PSS and increases its active specific surface area per unit. Simultaneously, the incorporation of liquid metal (LM) enhances both the mechanical and healing properties of the LM-CNT-PEDOT:PSS electrode. The flexible and self-healing MSC based on wrinkled LM-CNT-PEDOT:PSS shows a remarkable specific capacitance of 114.29 mF cm-2 and a high areal energy density of 15.47 µW h cm-2. Furthermore, the electrochemical performance of the healed MSC retained 90.01% of its initial performance, and the MSC unit can be arbitrarily integrated according to various energy and voltage requirements through the healing properties of LM-CNT-PEDOT:PSS, widening the range of applications in next-generation microelectronic devices. The wrinkled LM-CNT-PEDOT:PSS film is utilized for the fabrication of a highly sensitive strain sensor. Simultaneously, the prepared sensor can be seamlessly integrated with wireless charging and MSC to facilitate convenient monitoring of physiological signals, thereby offering an effective solution for the advancement of wearable technology and self-powered systems.

EHWPTCRN-energy harvesting using wireless power transfer for cognitive radio networks with 802.11 (DCF) MAC protocol

EHWPTCRN-energy harvesting using wireless power transfer for cognitive radio networks with 802.11 (DCF) MAC protocol

Empowering talkative power technology in wireless power transfer with machine learning

Empowering talkative power technology in wireless power transfer with machine learning

A foreign object detection method based on a laminated coil for wireless power transfer

Foreign objects in magnetically coupled resonant wireless power transfer (MCR-WPT) systems cause eddy effects, reducing efficiency and raising the temperature. To address this, a high-frequency multilayer detection coil and composite topology circuit are designed to enhance sensitivity by dynamically adjusting component parameters. Verified through Maxwell simulation, the proposed method improves detection efficiency by 46% and eliminates blind spots compared to square coils. The detection range expands by 66% with a 3 × 3 reverse series-laminated coil, effectively decoupling sub-coils and broadening coverage. Experimental results show accurate detection of various foreign objects, such as iron and copper, by analyzing changes in magnetic fields and detection coil voltage. This approach enhances MCR-WPT system safety and efficiency, making it suitable for complex environments.

State-of-the-Art and Advancement of Charging Infrastructure in Electric Mobility: An Integrated Review

Electric mobility is attracting significant attention in the current era due to its environmental benefits, sustainable transportation options, and the absence of carbon emissions. However, challenges such as the high price of batteries, inefficient charging techniques, and compatibility linking the charging station with electric vehicles (EVs) must be addressed. This article reviews advancements and identifies challenges in charging infrastructure for electric mobility. This study incorporates and analyzes an integrated review of approximately 223 research articles. Current research trends and states of charging infrastructure are prepared as per the Web of Science (WoS) database from 2013 to 2023. In light of recent extensions in wireless power transfer technology, including capacitive, inductive, and magnetic gear topology, are presented to advance the charging infrastructure. Different charging tactics based on power source, such as level-1 AC, level-2 AC, level-3 DC fast, and level-3 DC ultra-rapid charging, related to charging infrastructure are addressed. The vehicle-to-grid (V2G) integration methodology is addressed to construct a smart city by presenting the transfer of power and related data through linkage and moving systems. The exploration of artificial intelligence, global connectivity of electric vehicles (EVs), sun-to-vehicle (S2V), and vehicle-to-everything (V2X) techniques with EVs is conducted to enhance and progress the charging infrastructure. Key barriers associated with charging infrastructure are identified.

Analysis of the Parity-Time Symmetry Model in the Receiver-Based Wireless Power Transfer

Parity-time (PT) symmetry has made encouraging progress in wireless power transmission (WPT), exhibiting significant advantages in terms of system robustness and transmission efficiency. However, there are still challenges that need to be addressed, particularly when classical schemes operate at a fixed frequency in the weak coupling region, where even minor changes in coupling strength can result in excessive current surges. This paper introduced a novel PT-symmetric WPT system featuring negative resistance constructed on the receiver side. We first established a theoretical framework for the classical two-coil PT-symmetric magnetically coupled resonant WPT system and subsequently extended it to incorporate the PT-symmetric WPT system with negative resistance on the receiver. This topological coil configuration facilitated stable power delivery over a broader range, with the capability of self-tuning frequency without requiring additional frequency modulation. This adaptability enabled the system to cater to diverse scenarios and opens up a novel avenue for practical applications of PT symmetry in WPT. Finally, we designed a 10 W prototype to demonstrate the effectiveness of our topology, and the experimental results aligned with our theoretical calculations, validating the feasibility and potential of our PT-symmetric WPT system.

Analysis and design of U-shaped wireless power transfer system for humanoid robots

Analysis and design of U-shaped wireless power transfer system for humanoid robots

Wireless Power Transmission by MEMS Vibration Energy Harvester Using Electromagnetic Torque

Wireless Power Transmission by MEMS Vibration Energy Harvester Using Electromagnetic Torque

Research on magnetic field distribution characteristics of 2G-HTS dynamo in superconducting wireless power supply applications

Abstract The high-temperature superconducting (HTS) dynamo injects direct current (DC) into the winging of superconducting machines through non-electrical contact, solving issues such as thermal leakage in traditional current leads and current decay due to flux motion, joint resistance and AC losses. However, it has been observed that the DC output voltage decreases with an increasing air gap between the rotor magnet and HTS stator. To increase the output of the HTS dynamo at a fixed gap, this study employs an efficient numerical model based on the equivalent current method to investigate the magnetic field distribution of the magnets with different structural parameters. The relationship between the magnetic field distribution of the rotor magnet and the open-circuit voltage of the stator is established and extensively validated against simulation modeling and experimental data. Experimental results indicate that the rotor’s magnetic field distribution and the stator’s magnetic field penetration influence the open circuit voltage of the HTS dynamo. Specifically, when the distance between adjacent magnets is large, the magnetic field penetration occurs only on both sides of the stator, causing circuit voltage to increase initially and then decrease with the magnet distance decreases. A reverse point opposite to the magnetic field direction on both sides is generated at the center of the stator when the distance decreases further, which increases the average induced current density, and suppresses the downward trend. By optimizing the magnetic field distribution of the rotor magnets on the stator, the DC output power of the dynamo can be effectively improved. This model and the results contained in this article provide a comprehensive theoretical basis for researchers to compare and optimize their own modeling and experiment of the HTS dynamo.

Enhancing power quality in wireless DC power supplies through active power filtering: A computer simulation approach

This paper presents a computer simulation model for a high-power factor wireless DC power supply system, integrating an active power filter (APF) at the rectifier stage on the transmitter side using a rectifier boost technique. The APF, employing a MOSFET switch regulated by active pulse width modulation (APWM) within a current control loop, addresses pulsating and distorted AC supply currents caused by non-linear loads. A robust closed-loop control mechanism, including a subtractor circuit, proportional-integral (PI) controller, and comparator, ensures the generation of a continuous sinusoidal waveform synchronized with the supply voltage. The model utilizes a high-frequency inverter to convert DC to AC, which is then wirelessly transmitted via wireless power transfer (WPT) technology and converted back to DC by a high-frequency rectifier. MATLAB/Simulink simulation results show a significant reduction in total harmonic distortion (THD) of the AC supply current, complying with IEEE 519 standards. Selected results are presented to verify the proposed method's effectiveness in reducing harmonic distortions and enhancing power quality. This study highlights the advantages of WPT in scenarios where traditional wired connections are impractical and underscores the potential of this system for real-world applications, particularly in developing high-power factor wireless DC power supply systems.

Sum computation rate maximization for wireless powered OFDMA-based mobile edge computing network

The wireless power transfer (WPT) and mobile edge computing (MEC) technologies have been advocated as the prospective effective solution for future wireless networks. This paper introduces a multi-user WPT-MEC system, where a sum computation rate (SCR) maximization design by jointly optimizing the WPT duration, the allocation of the subcarrier selection indicator of each user, each user’s transmit power, and the parameters related to different offload modes at each user is considered. In such a system, the hybrid access point (AP) broadcasts radio frequency (RF) energy intended for users to harvest, subsequently enabling users to transmit their computation tasks to the MEC server via the orthogonal frequency division multiple access (OFDMA) protocol. To address this non-convexity SCR maximization problem, a decomposition optimization is proposed. In the top-problem, the DRL-based deep neural network (DNN) model is applied to realize the computation selection indicator and subcarrier selection indicator among each user. In the sub-problem, for the binary offloading mode, an efficient two-stage algorithm with golden section search and intrinsic properties is utilized to determine the optimal values of remaining parameters. For the partial offloading mode, the problem is reformulated by introducing new variables and then the convex optimization techniques are utilized to efficiently obtain the corresponding solutions. Simulation results demonstrate the proposed approach outperforms the benchmark methods considered in both binary and partial offloading modes.

Design and Verification of Adaptive CC/CV Mode Switching Wireless Power Transfer System for UAVs Based on High Switching Frequency Single-Switch LC Inverter

Design and Verification of Adaptive CC/CV Mode Switching Wireless Power Transfer System for UAVs Based on High Switching Frequency Single-Switch <i>LC</i> Inverter

Analysis and Implementation of Underwater Single Capacitive Coupled Simultaneous Wireless Power and Bidirectional Data Transfer System

Analysis and Implementation of Underwater Single Capacitive Coupled Simultaneous Wireless Power and Bidirectional Data Transfer System

Omnidirectional Wireless Power Transfer Based on Constant Coupling Polarity Concept

Omnidirectional Wireless Power Transfer Based on Constant Coupling Polarity Concept

Resonant Tuning Rectifier for Parallel Compensated Receivers in Wireless Power Transfer

Resonant Tuning Rectifier for Parallel Compensated Receivers in Wireless Power Transfer

Power Transmission Technology Using Wireless Network

In this paper, we have presented the concept of wireless transmission i.e. power transmission without using any type of the electrical conductor and/or wires. We have presented an idea that is discussed here about how electrical energy can be transmitted as microwaves so that to reduce the transmission, allocation and other types of losses. Such technique is known as Microwave Power Transmission (MPT). We have also presented and correlated several aspects with the currently available Power transmission systems to the related history of wireless power transmission systems and also the related developmental changes. The basic design, merits and demerits, applications of Wireless Power Transmission are also discussed . The paper describes the various types of WPT technologies; Inductive Coupling, Magnetic Resonance and Radio Frequency (RF) technology. It also discusses the advantages and shortfalls of each type. An extensive survey of past works was discussed. Results from the research findings showed that distance and conversion efficiency were limiting factors in implementing wireless transfer technology

Minimization of Task Completion Time in Wireless Powered Mobile Edge–Cloud Computing Networks

Minimization of Task Completion Time in Wireless Powered Mobile Edge–Cloud Computing Networks