Wireless Energy Transmission Technology Research Articles

Development of bacteriostatic central venous port using photobiomodulation: a comparative in vitro study

Photobiomodulation (PBM) occurs when a cell is exposed to low energy intensities. A novel central venous port (CVP) with light-emitting diodes (LEDs) that emits red light with a wavelength of 680 nm via wireless energy transmission technology has been established. This comparative in vitro study examined whether PBM can reduce the growth of methicillin-resistant Staphylococcus aureus (MRSA), a common cause of central venous (CV) infections, in vitro. In this comparative in vitro study, the red light with a wavelength of 680 nm was used to irradiate an MRSA suspension in phosphate-buffered saline for 7.5, 15, 30, or 60 min in a 3.5 cm Petri dish with an area of 8.5 cm2. The total energy was 85 J at 7.5 min, 170 J at 15 min, 340 J at 30 min, and 680 J at 60 min. Six dishes for each time and 6 temperature-controlled samples were prepared. Each sample was incubated overnight at 37℃. The Shapiro-wilk test was used to determine whether the data were normally distributed. The numbers of colonies were counted and compared using one-factor ANOVA and Bonferroni’s post-hoc test. The mean numbers of colonies in the control group were 60.3, where the numbers of colonies in the irradiated group were 51.4 at 7.5 min, 53.5 at 15 min, 44.6 at 30 min, 34.3 at 60 min. The mean number of colonies in the 60 min irradiated group differed significantly from that in the control, 7.5 min, and 15 min groups. The Bonferroni’s post-hoc test showed significant difference in the number of colonies between control vs. 30 min control vs. 60 min, 7.5 min vs. 60 min, 15 min vs. 60 min. PBM with 680 nm LEDs on MRSA for 340 J at 30 min and 680 J at 60 min inhibited the growth of cell colonies. These findings support the use of photobiomodulation in Central venous port to prevent CV access port-Blood stream infection.

A study on GaN-based high-efficiency class E power amplifier circuits at medium-low frequencies

Abstract In this paper, a high-power amplifier is designed to address the challenges of low transmission power and poor efficiency in wireless energy transmission technology at low frequencies. The design is based on a class E power amplifier circuit. The theoretical analysis is conducted to determine transistor selection and the static DC operating point. Load traction technology is employed to match the load impedance of the power amplifier, ensuring highly efficient and unified power additional efficiency, and output power. To enhance system stability and feedback compensation, gate series resistance and parallel capacitors are incorporated. Simulation results demonstrate that the designed power amplifier achieves an output power of 48 dBm with a power additive efficiency (PAE) of 85%. Furthermore, the third-order intermodulation component reaches 70 dBm, indicating concentrated output energy and high linearity in the amplifier system. Experimental results validate the consistency between theoretical analysis and model simulation, confirming the stability of the designed power amplifier circuit, and successfully achieving energy-efficient, high-power transmission.

CSCT: Charging Scheduling for Maximizing Coverage of Targets in WRSNs

In recent years, wireless rechargeable sensor networks (WRSNs), as a crucial technology in cyber-physical-social systems (CPSSs), have gradually become a hotspot of research, with the development of wireless energy transmission technology. In previous works, the objective is to maximize the survival rate of sensor nodes. However, in this article, we focus on maintaining more targets. First, it details the charging scheduling problem of maximizing coverage of targets (CoT) in on-demand charging architecture of WRSNs. Also, the problem is formalized as a multiple-objective optimization problem, which aims at maximizing the CoT and the energy efficiency simultaneously. After that, the charging scheduling for maximizing coverage of targets (CSCT) scheme is proposed to achieve the above objectives. Then, the problem is reformulated as a Deadline-TSP problem that is NP-hard. To address this problem, we design an energy predictive model and propose the CSCT with an n-path (n-CSCT) scheme that has an O(|N|ⁿ) computational complexity. In addition, the resurrection of sensor nodes is considered in this article. Thus, the n-CSCT with node resurrection (n-CSCT-R) scheme is proposed for this case. Finally, we validate the effectiveness of the proposed schemes via extensive simulations.

New energy vehicle technology research - Charging technology

In recent years, Chinas economic development is becoming more and more rapid, leading to the increasingly serious pollution emission problem of traditional fuel vehicles. In order to solve the environmental problems, the transformation of automobiles has become an urgent problem. At the present stage, electric vehicles are also widely concerned by all sectors of society because of their low carbon emissions, energy saving and low use cost. With the rapid growth of electric vehicle sales, the demand for charging piles is rising, and the mainstream charging facilities for new energy vehicles are still in short supply. Therefore, we need to focus on efficient wireless charging to solve the major problems in the current electric vehicle industry. This paper analyzes the wireless dynamic energy transmission technology, extending the service life of the battery, how to reduce the cost, the optimization of coil parameters design, the offset of transmission coil and receiving coil, foreign body detection and overheating problems.

Research on the application of wireless energy transmission technology in smart grid

Abstract With the continuous development of wireless energy transmission technology, the role of wireless rechargeable sensor networks (WRSNs) in smart grids has become more and more important. In this paper, after fully investigating the application of wireless energy transmission technology in smart grids, the solution vector of SFLA is discretized, and the IMSFLA model based on the hybrid frog jump algorithm is proposed to solve the wireless energy transmission planning problem in the smart grid. Finally, it is applied to the optimal design of the charging scheme of WRSNs, and the simulation results of the IMSFLA algorithm are compared and analyzed with those of the Taboo Search (TS) algorithm after exploring its wireless transmission performance. In terms of energy utilization, when the number of nodes is increased to 550, the energy utilization of IMSFLA algorithm is improved by 7% compared to TS algorithm, and when the number of nodes is increased to 550-800, the optimized results of TS algorithm deviates significantly more compared to IMSFLA algorithm. This indicates that the IMSFLA algorithm designed in this paper has a better effect on the optimization of the charging scheme of wireless rechargeable sensor networks, which is of great practical significance for improving the stability of the smart grid.

Application of wireless energy transmission technology into central venous ports with light-emitting diodes.

Implantable central venous (CV) ports are widely used for chemotherapy and parenteral nutrition. Generally, CV ports are used safely; however, some patients suffer from drug leakage around the port septum due to mispuncture. Therefore, we developed a CV port that is visible under the skin. We created a prototype of a CV port using a 3D printer. Three red light-emitting diodes (LEDs) were attached around the septum that made the puncture site visible by applying wireless energy transmission technology using electromagnetic resonance. The CV port was implanted under the skin of pork rose meat. The thickness of the skin of pork loin was measured. Fifteen medical doctors participated in the study to visually confirm the lighted CV port. The visibility of the center of the septum with and without lights was scored 0 as non-diagnostic; 1, slightly visible; 2, well visible; and 3, obviously visible. The visibility with or without lights was assessed. The relationship between the years of experience and the visibility score was assessed. The Wilcoxon test was used for statistical analysis. LEDs were easily transmitted through the skin of pork rose meat. The median visibility scores with or without lights were 2 (range, 1-3) and 3 (range, 1-3), respectively (p = 0.005). No significant relationship was found between experience and visibility score (p = 0.289). CV ports with LEDs can be easily recognized compared with those without LEDs. This technique may contribute to medical safety by improving its visibility to avoid mispuncture.

Principles and applications of wireless energy transmission

In this day and age, people's lives are inextricably linked to electricity, which is being used more and more in everyday life. The traditional transmission of electrical energy usually uses materials such as metal wires and cables as the transmission medium, and the losses and potential damage (line deterioration, tip discharges) caused by this transmission medium are inevitable. The introduction of radio has been very effective in reducing this situation, and the development of Wireless Power Transfer (WPT) technology has seen three major developments since then, with Tesla lighting a phosphorescent lamp at the Colombian World's Fair in 1893, igniting hopes for WPT. This new way of transmitting electrical energy has expanded the imagination of people in terms of power supply methods by making it possible to provide more freedom in situations where cable charging is not suitable.The working theory, fundamental design, and potential applications of wireless energy transmission technology are covered in this study. By doing this, it offers insight into the development and use of wireless energy transmission technology as it is now. In the end, it is envisaged that the market will adopt wireless energy transfer technology extensively.

An Efficiency Optimization Strategy for Electric Vehicle Wireless Energy Transmission System

Magnetic coupling resonant wireless energy transmission technology has become an important research direction for electric vehicle wireless charging systems. This paper proposes an efficiency optimization strategy for the electric vehicle wireless energy transmission system based on LCL-S topology to improve the efficiency of electric vehicle magnetic coupling resonant wireless charging. This paper analyzes the optimization method of system efficiency based on LCL-S topology, establishes an experimental model in MATLAB/Simulink simulation software, and verifies it with the control variable method. The experiment shows that the efficiency optimization strategy based on the LCL-S topology proposed in this paper can effectively improve the system transmission efficiency and stabilize the transmission efficiency at a higher level faster.

Analysis of Laser Cell Response Characteristics under Different Irradiation Conditions

Although the application of laser wireless energy transmission technology in many fields such as UAV power supply is increasing, the laser incidence angle and beam shift remain the key factors limiting the efficiency of long-range laser wireless energy transmission. In this study, a laser cell response test platform was built to measure and analyze the response characteristics of a laser cell under different laser incidence angles and beam shifts. The results show that the increase in the incident angle intensifies the reflection on the irradiated surface, resulting in a linear decrease in the power density received by the laser cell, which eventually leads to a significant decrease in the output power, and the output power tends to be close to 0 when the incident angle exceeds 75°. The increase in the beam offset distance increases the reverse bias of the cell, which is the main reason for the significant decrease in the output power. The local irradiation also leads to an increase in the heat generation power; when the beam coverage is below 50%, the overall output power tends to be close to 0. This study provides a reference for improving the laser wireless energy transmission efficiency and laser cell optimization.

Attention-Shared Multi-Agent Actor-Critic-Based Deep Reinforcement Learning Approach for Mobile Charging Dynamic Scheduling in Wireless Rechargeable Sensor Networks.

The breakthrough of wireless energy transmission (WET) technology has greatly promoted the wireless rechargeable sensor networks (WRSNs). A promising method to overcome the energy constraint problem in WRSNs is mobile charging by employing a mobile charger to charge sensors via WET. Recently, more and more studies have been conducted for mobile charging scheduling under dynamic charging environments, ignoring the consideration of the joint charging sequence scheduling and charging ratio control (JSSRC) optimal design. This paper will propose a novel attention-shared multi-agent actor–critic-based deep reinforcement learning approach for JSSRC (AMADRL-JSSRC). In AMADRL-JSSRC, we employ two heterogeneous agents named charging sequence scheduler and charging ratio controller with an independent actor network and critic network. Meanwhile, we design the reward function for them, respectively, by considering the tour length and the number of dead sensors. The AMADRL-JSSRC trains decentralized policies in multi-agent environments, using a centralized computing critic network to share an attention mechanism, and it selects relevant policy information for each agent at every charging decision. Simulation results demonstrate that the proposed AMADRL-JSSRC can efficiently prolong the lifetime of the network and reduce the number of death sensors compared with the baseline algorithms.

Ground-based investigation of a directional, flexible, and wireless concentrated solar energy transmission system

Solar energy in space is more intensive and continuous compared to that on the Earth, and thus, is encouraged by governments across the world to be utilized for human beings. The continuity of the space sunlight has a great potential to overcome the bottleneck of the variability and intermittency in time and space for ground-based solar energy applications. Space solar power station (SSPS) is known as intermedia that can harvest the space solar energy and transmit it wirelessly to the end-user. However, the current wireless energy transmission via microwave or laser suffers from low energy transmission efficiency because of excessive energy conversion processes. Wireless energy transmission via sunlight without any intermediate energy conversion process was proposed previously theoretically for high energy transmission efficiency, but it also lacks practicability due to heavyweight and inflexibility. Therefore, although promising, practical sunlight-based wireless energy transmission proposals have not ever been presented. Here, through component and structure optimizations in theoretical and experimental approaches, a novel and more practical concentrated solar energy wireless transmission system that transmits the harvested sunlight via lightweight optical fibers is proposed in this paper. It uses a Fresnel lens to collect concentrated solar energy and then, the utilized optical fiber can steer the collected energy to the collimator flexibly. At last, a parallel sunlight beam can be emitted from the collimator to the target end-user. Results show that the transmitter efficiency versus optical fiber length exhibited a linear relationship from both theoretical and experimental approaches. the cloud effect harmed the energy transmission. A maximum transmitter energy transmission efficiency of 52.0% could be attained experimentally. Compared with the performance in the no-cloud condition, the gained voltage could be declined by 37% ∼ 48%. The bending of the optical fiber seemed to not affect much on the energy transmission performance, which guarantees a flexible energy transmission. Besides, the power/weight ratio was increased by 17.0% compared to its counterpart. The innovation of this paper is to reduce the gap between theoretical and practical feasibilities for the proposed system. This paper experimentally demonstrates the feasibility of a wireless concentrated solar energy transmission technology, which promotes the application of SSPS and related aerospace applications.

Cooperative Recharge Scheme Based on a Hamiltonian Path in Mobile Wireless Rechargeable Sensor Networks

The energy problem and limited capacity of batteries have been fundamental constraints in many wireless sensor network (WSN) applications. For WSN, the wireless energy transmission technology based on magnetic resonance coupling is a promising energy transmission technology. To reduce the cost and energy consumption during charging in mobile wireless rechargeable sensor networks (MWRSNs), a cooperative mobile charging mechanism based on the Hamiltonian path is proposed in this paper. To improve the charging task interval, we study the use of a mobile charger (MC) as a mobile sink node to collect the data in this paper. Then, we used the sink and the charging sensors selected by the MC to construct the undirected complete graph. Finally, the Euclidean distance between nodes is used as the edge weight and a Hamiltonian loop is found by using the improved Clark–Wright (C-W) saving algorithm to solve the problem of charging a rechargeable sensor network. In addition to the energy usage efficiency (EUE) and the network lifetime, the average energy loss per unit time is considered as the evaluation index according to the impact of the MC on the energy consumption during charging. The simulation results show that the proposed scheme increases the average network lifetime, decreases the average energy loss per unit time, and improves the EUE.

Region Orientation and Converging Magnetic Energy Transmission Based on Novel Structure

Background: As wireless energy transmission technology advances, the demand for energy directional transmission increases. Objective: Transfer of energy in the specified direction and increase in transmission power. Methods: A novel three-coil transmitting structure was proposed, which can transmit energy to a specified single or multiple space regions, and enhance the magnetic field strength in a single direction by magnetic field vector synthesis to improve the transmission power. Results: Combined with Mathcad numerical calculation and Maxwell simulation analysis, the experimental platform was built and the magnetic focusi of the proposed novel structure was experimentally verified. Conclusion: The novel emission structure can effectively perform directional energy transmission and increase the transmission power by 2~3 times in a single direction at the cost of 10%~15% efficiency loss.

Wireless Energy Transmission Link Optimization considering Microwave Energy Relay

With the widespread application of intelligent unmanned units and the development of wireless energy transmission technology, it has become an urgent requirement in the field of using wireless power transmission to extend the continuous working time of unmanned units. To improve the wireless transmission energy efficiency in practical application as much as possible based on the current development level of wireless transmission technology, this paper first enumerates and analyzes existing wireless energy supply methods and shows that microwave wireless energy transmission technology is most suitable in this study. Then, the necessity of power transmission relay in long-distance microwave wireless power transmission is discussed. Based on the idea of microwave energy relay transmission, the paper constructs a microwave wireless transmission link planning model which considers power relay and uses the evolutionary algorithm to solve the wireless transmission link planning model with two-layer optimization. Finally, the results show that, when the wireless transmission distance exceeds a certain threshold, adding relay nodes to the link can improve the energy transmission efficiency from the power supply node to the power receiving node.

Design of Strained Ge Schottky Diode on Si Substrate for Microwave Rectifier Circuit

In recent years, wireless energy transmission technology has developed rapidly and has received increasing attention in the industry. For microwave wireless energy transfer system applications, Ge Schottky diodes as the core components of the rectifier circuit are commonly used. Compared with Ge semiconductor, strained Ge semiconductor on Si substrate has the advantages of compatibility with Si process, low cost, and high electron mobility. It is an ideal replacement material for Ge semiconductor applications. In view of this, based on the model of the relationship between the performance of strained Ge semiconductor on Si substrate Schottky diodes and the geometric parameters of the device and the physical parameters of the material, Silvaco TCAD and ADS simulation software are jointly used to propose a novel strained Ge semiconductor on Si substrate Schottky diode for microwave rectification circuit. Simulation results show that the strained Ge semiconductor on Si substrate Schottky diode has a rectification efficiency of 70.1% when the input of the rectifier circuit is 20 dBm, the load resistance is R = 1000 Ω, and the load capacitance is C = 100 pF. Compared with traditional Ge Schottky diodes, this optimal operating point is closer to a low energy density, which is beneficial to a wide range of energy absorption. Studies have shown the feasibility of replacing Ge Schottky diodes. The research in this paper can provide valuable reference for the design and development of the core components of the rectifier circuit of the microwave infinite energy transmission system.

A survey of video capsule endoscope system based on wireless energy transfer technology

The wireless capsule endoscope system allows clinicians to directly observe the image of the inner wall of the human gastrointestinal tract and obtain the most intuitive information at the lesion. Compared with traditional endoscopic detection technology, its painless, non-invasive, safe and convenient, full gastrointestinal detection features make this technology a research focus in the field of medical devices at home and abroad. As a new non-invasive detection technology for gastrointestinal diseases, the working time, image frame rate and image quality of the existing wireless capsule endoscope system cannot fully meet the needs in clinical applications. The cause of these problems lies in the capsule. The internal space of the speculum is limited, and only the button battery can be used as the energy source. Therefore, it is necessary to design a video capsule endoscope based on wireless energy transmission technology. This article is a review of Zhu Zhanquan, Xue Kaifeng, Lu Ruiqi and other scholars.

Context–Problem Network and Quantitative Method of Patent Analysis: A Case Study of Wireless Energy Transmission Technology

Identification of prevalent problems is an important process of strategic innovation for stakeholders of trending technologies. This paper proposes a systematic and replicable method of patent analysis to identify problems to be solved requisite for sustainable technology planning and development, by implementing the concept of ‘context’ to facilitate problem identification. The main concept of the method entails the importance of the connections between contextual information and problems to provide more focused, relevant, and constructive insights essential for instating goals for research and development activities. These context–problem entities and their entwined connections are discovered using keyword pattern matching, grammar-based text mining, and co-word analysis techniques. The intermediary outputs are then utilized to generate the proposed context–problem network (CP net) for social network, grammar, and quantitative data analysis. For verification, our method was applied to 737 patents in the wireless energy transmission technology domain, successfully yielding CP net data. The detailed analysis of the resulting CP net data delivered meaningful information in the wireless charging technology field: The main contexts, “batteries”, “power transmission coils”, and “cores”, are found to be most relevant to the main problems, “maximizing coupling efficiency”, “minimizing DC signal components”, and “charging batteries”. The results provide a wide range of informative perspectives for individuals, the scientific community, corporate, and market-level stakeholders. Furthermore, the method of this study can be applicable to various technologies since it is independent of specific subject domains. Future research directions aim to improve this method for better quality and modeling of contexts and problems.

Performance Analysis for the Magnetically Coupled Resonant Wireless Energy Transmission System

As a new wireless energy transmission technology, magnetically coupled resonant wireless energy transmission system (MCRETS) is not easily affected by obstacles in the transmission process, and the transmission distance is relatively far. However, how to balance the relationship between transmission efficiency and power to achieve optimal performance is still a huge challenge. In addition, few studies have theoretically investigated the factors affecting the wireless energy transmission system to obtain an optimal solution. Here, through unprecedented theoretical analysis, we find the exact parameters of system optimization and verify them by simulation and experiments. First, the optimal topology of MCRETS is obtained through theoretical analysis and comparison of topologies. Second, to improve the transmission performance of MCRETS, its impact factors, including transmission distance, resonant frequency, relay coil, and relative position of launch and receiving coils, are analyzed in detail to get accurate parameters. Furthermore, based on the analysis, we propose an unprecedented concept for balancing optimal efficiency and power, which is named the power product. Finally, the effectiveness of the proposed method is verified through analysis and experimental results. These findings shed light on the relationship between efficiency and power and provide a comprehensive theoretical basis for subsequent research.

Wireless Electric Energy Transmission through Various Isolated Solid Media Based on Triboelectric Nanogenerator

AbstractWireless electric energy transmission is an important energy supply technology. However, most wireless energy supply based on electromagnetic induction cannot be used for energy transmission through a metal chamber. Herein, a novel idea for wireless electric energy transmission through various isolated solid media based on triboelectric nanogenerator (TENG) is presented. The electric energy is first transformed into mechanical vibration energy in mechanical wave that can propagate well in solid medium, and then the vibration energy is harvested by a TENG. By employing the spring steel sheets and freestanding triboelectric‐layer structure, the vibration TENG as an energy conversion unit has the advantages of high efficiency and facilitation, boosting this wireless energy transmission technology to be an alternative way of delivering electric energy through metal medium. The working principle and output performance have been systematically studied. A commercial capacitor can be charged from 0 to 10 V in 33 and 86 s isolated by an acrylic plate and a copper plate in thickness of 3 mm, respectively. The wireless electric transmission technology is also applied to deliver electric energy into a vacuum glove box and across glass wall successfully. This novel technology has great potential applications in implantable microelectronic devices, encrypted wireless communication, and even nondestructive testing.

A coverage-aware energy replenishment scheme for wireless rechargeable sensor networks

Wireless rechargeable sensor networks are becoming crucial and important in recent years for the advancement of wireless energy transmission technology. The previous research showed that not all of sensors can be recharged due to the limitation of energy capacity that mobile chargers can carry. If a sensor playing a critical role in a sensing task cannot function as usual due to exhausted energy, then the sensing task will be interrupted. Therefore, this paper proposes a novel recharging mechanism taking the coverage of sensors into consideration such that mobile chargers can recharge the sensor with a high coverage degree and the network lifetime can be efficiently sustained. The coverage degree of each sensor depends on its contribution to the sensing task, including the coverage and connectivity capabilities. Based on the coverage degree, the sensor with a higher coverage degree will be properly recharged to extend the network lifetime. Simulation results show that the proposed mechanism performs better against the related work in network lifetime.