Wireless Power Transmission Research Articles

Research on Wireless Power Transmission Technology for Underground Deformation 3-D Measurement Device

Research on Wireless Power Transmission Technology for Underground Deformation 3-D Measurement Device

Impact of coil envelope on the coupling coefficient in magnetic induction wireless power transmission systems

Abstract In recent years, research in the field of wireless power transmission by magnetic induction has increased due to the diversity of applications, such as medicine, electronics, and transport, which require this technology. However, despite its maturity to date, this technology has had difficulty gaining acceptance due to the short transmission distance and low coupling coefficient between the transmitting and receiving coils. Generally, these coils need to be protected by an envelope. However, the impact of the nature of the envelope on the coupling coefficient has not studied. This work focuses on the impact of the nature of the coil protection envelope on the coupling coefficient. Three-dimensional flat spiral coils and the protective envelope are modelled and subjected to parametric analysis with variable air gaps and frequencies using ANSYS-Electronics Maxwell 2022 R1 software with the finite element method (FEM). Simulation results show that a coil protected by an insulating envelope has a higher coupling coefficient compared to one protected by a conducting material. It is also shown that the coupling coefficient decreases as the operating frequencies increases. The ohmic losses in coils protected by an insulating envelope are greater than those in coils protected by a conductive material.

Tunable Negative Permittivity and Magnetic Properties of Ag/BLM Ceramic Metacomposites

Abstract Percolation composites with tunable negative permittivity have garnered significant attention due to their potential use in the field of electromagnetic interference shielding, near field amplification, antennas, and sensors. However, studies on the magnetic property at a frequency range of 100 MHz to 1 GHz are relatively scarce. The objective of this study was to examine the magnetic property and adjustable negative permittivity of silver/La-doped barium ferrite(Ag/BLM) ceramic metacomposites. In this study, Ag/BLM ceramic metacomposites with varying Ag content were prepared using a simple impregnation-calcination method. We investigate the permittivity, reactance, and permeability of Ag/BLM ceramic metacomposites at 100 MHz ~ 1GHz. The findings indicate that the percolation threshold for Ag/BLM ceramic metacomposites with x wt% is between 10 wt% and 19 wt%. When Ag content reaches 19 wt%, it creates a conductive network that generates a high number of free electrons. This leads to low-frequency plasma states and results in negative permittivity. Meanwhile, the permeability of Ag/BLM ceramic metacomposites shows the frequency dispersion due to the magnetic resonance and eddy current. Therefore, this study's findings suggest that composites with tunable negative permittivity and permeability may be developed and utilised for microwave absorption, antenna design, and wireless power transmission.

High energy circular Pearcey beams generation using phase-only metasurfaces with complex function fitting method

In this paper, we use electromagnetic metasurfaces for the first time to generate the circular Pearcey beam. A complex function fitting method is proposed for generating the circular Pearcey beam, which can improve electric field intensity at focusing location, resulting in a high energy circular Pearcey beam with an increase of 31.77% compared to the traditional Pearcey beam design. A slowly varying envelope is applied to describe the amplitude of the Pearcey function. Meanwhile, considering the oscillation property of the Pearcey function, an additional phase is added to its original phase. Furthermore, the double-phase hologram (DPH) method is developed to realize phase-only metasurface design. Four full wave electromagnetic simulations are finished, which prove the effectiveness of our proposed Pearcey function fitting method and phase-only metasurface design. Two 10 GHz transmissive metasurfaces were designed, fabricated, and experimented to further validate our design. This circular Pearcey beam design is useful in near field wireless communication, microwave wireless power transmission, and simultaneous wireless information and power transfer.

Structure optimization of transmission coil of wireless power transmission system for rail transit vehicles

Abstract To solve the transmission efficiency problem of traditional wireless energy systems applied to rail transit vehicles. In this paper, the key components of a wireless power transmission system, such as the transmission efficiency of the transmission coil and the poor anti-deviation ability of the coil, are studied. Firstly, this paper analyzes the traditional planar circular and square coil shapes, analyzes the magnetic field characteristics of the traditional transmission coil structures by ANSYS Maxwell simulation software, and obtains the advantages and disadvantages of different coil structures. According to the analysis structure, the coil structure is optimized and improved, and the coil structure form of the combined coil is put forward. Through the comparative analysis of finite element simulation software, it is attested that combined coil structure has a significant improvement in transmission efficiency and anti-deviation ability.

Wireless power transfer systems and wireless charging design between electric vehicles

The foundations of wireless power transmission were laid down by Nikola Tesla many years ago, by transmitting energy wirelessly using a Tesla coil. Nikola Tesla's work many years ago pioneered wireless power transmission studies today. Wireless power transmission, which telephone companies have focused on in recent years, also forms the basis for charging electric vehicles. One of the main reasons why lithium ion batteries are preferred in electric vehicles is the advantages they offer regarding the charging process. These batteries provide longer range compared to other battery types, thanks to their high energy density, that is, they can store more energy compared to their size. At the same time, faster charging capabilities are a great advantage for electric vehicle owners. As a result, charging technology is very important in electric vehicles. In this study, we will present a design project that enables electric vehicles, which have become more common in daily life with the developing technology, to transfer their charge to each other contactlessly in emergency situations. In the design, the receiver coil will be placed on the front hood of the vehicle and the transmitter coil will be placed on the rear hood of the vehicle. There will be a distance sensor where the transmitter coil is located, thanks to this sensor, the distance can be adjusted. When the vehicles reach the optimum distance, the distance sensor will give a warning and be charged enough to go to the nearest charging station. In addition, thanks to the ease of sharing for emergencies, emergency vehicles (ambulances) will be able to quickly receive energy from another vehicle and continue their duties without interruption. In this way, we will reduce the towing cost of electric and hybrid vehicles and provide drivers with uninterrupted driving. In the wireless charging station; We will offer many advantages such as getting rid of cable clutter, providing ease of use, compatibility with all devices, multiple charging and durability.

Transmit Power Optimization in Multihop Amplify-and-Forward Relay Systems with Simultaneous Wireless Information and Power Transfer

In this paper, we study a multi-hop amplify-and-forward (AF) simultaneous wireless information and power transmission (SWIPT) relay system. Each relay node harvests power using a power split (PS) method from a portion of the received signal, amplifies the remaining received signal, and passes it to the next relay. Based on this system model and signal flow, we derived and solved the convex power minimization problem with the optimal PS ratio. In this case, it was found that using the optimal PS ratio consumed a lower amount of power than when using a fixed PS ratio (0.5). We then investigated the impact of processing cost on the AF-SWIPT system using decoding and forwarding SWIPT as benchmarks, and found that AF-SWIPT was superior.

Effect of cell structures on electrical degradation of GaAs laser power convertors after 1 MeV electron irradiation and structure-optimization for improving radiation resistance

Laser wireless power transfer (LWPT) technology holds significant promise for wireless power transmission in space, necessitating that high-efficiency GaAs laser power convertors (LPCs) have strong tolerance to high-energy particle radiation. Therefore, the degradation characteristics of GaAs LPCs with different architectures under 1 MeV electron irradiation were investigated. Experimental and simulation results demonstrate that LPCs with thicker bottom cells suffer from significantly more electrical degradation. The degradation is primarily due to a reduction in electron concentrations in the base of the bottom cells, which is considerably less pronounced as the thickness of the bottom cells decreases. Based on these analyses, thinning the thickness and optimizing the doping profile for the bottom cells are proposed to improve the radiation resistance of the LPCs. Simulations show that the electrical degradation of the optimized four-junction LPCs is notably less than that of the original four-junction LPCs under the same irradiation conditions, indicating that the proposed strategies effectively enhance the radiation resistance of the LPCs.

Summary of Wireless Charging Technology for Electric Vehicles

The rapid popularity of electric vehicles has promoted the rapid development of wireless charging technology. This paper reviews the current research progress and application status of wireless charging technology for electric vehicles. Inductive coupling, magnetic resonance coupling and non-directional radiofrequency radiation, three main wireless power transmission methods, including their principles and advantages, are introduced. In addition, the practical application of the technique, such as near field application and far field application, is also discussed. Finally, the development direction of wireless charging technology for electric vehicles in the future is looked forward, including the key technical paths of optimizing system design, improving energy transmission efficiency and reducing system cost. In summary, this paper aims to provide comprehensive theoretical support and practical guidance for the research and practice of wireless charging technology for electric vehicles.

Optimization of Coreless PCB Coils Based on a Modified Taguchi Tuning Method for WPT of Pedelec

The printed circuit board (PCB) winding coil offers advantages such as small size, high precision, high repeatability, and low cost, making it conducive to the miniaturization of electronic equipment and a popular choice in wireless power transmission systems. This paper aims to clarify the correlation between induction parameters and inductive capabilities using the orthogonal array of the modified Taguchi method for Pedelec applications. The conventional Taguchi method typically achieves only local optimization; however, this paper considers practical application conditions and combines experimental data to establish the initial values of the orthogonal array, thereby achieving global optimization. Additionally, the tuning process of the Taguchi method replaces physical experiments with simulations, enhancing optimization speed and reducing hardware implementation costs. The performance index for the proposed modified Taguchi tuning method is selected as a combination of the quality factor (Q) and coupling coefficient (k) to minimize AC resistance and improve system efficiency. To validate the proposed method, the designed coils were implemented and tested in a WPT system based on S–S compensation with a half-bridge topology. The experimental results demonstrate that the optimized PCB coil parameters derived from the proposed tuning method accurately validate the method’s effectiveness and accuracy. From the measured results with the proposed modified tuning method, the system efficiency is increased by 43.87% and the system transmitting power is increased by 28.51%.

Integrated RES With Intelligent MPPT For Efficient Power Generation & Wireless Transmission for PV Applications

The increasing global energy demand and the urgent need to shift to sustainable practices have made the integration of renewable energy sources (RESs) into distribution power systems imperative. This project's main objective is to implement rooftop photovoltaic (PV) systems as an essential part of low-voltage (LV) DC networks' building-integrated centralized generation Maximum Power Point Tracking (MPPT) using Artificial Neural Networks (ANNs) is used to maximize power extraction from photovoltaic (PV) panels and boost power generation efficiency, particularly in partially shaded circumstances. After that, the PV system's generated power is sent to a Luo converter, which effectively tracks and optimizes the power production. For wireless power transmission, the Luo converter's output is then fed into a high-frequency converter. This wireless power transmission improves the system's adaptability and scalability by facilitating smooth energy transfer without the requirement for physical connections. An isolation transformer is attached to the high-frequency converter's output in order to guarantee the system's dependability and safety. The high-frequency converter is isolated from the downstream components by the isolation transformer, which also offers protection against electrical risks. Finally, a battery made especially for use in electric vehicle (EV) applications receives the transformer's isolated output, which is also supplied to DC loads. Finally, we will use the MATLAB 2021a / Simulink program to do a number of numerical simulations in order to validate the suggested controls. The output voltage of 130v is stored in the battery if a voltage of 65 v is taken as output from the photovoltaic system.

Optimal Design of Multitarget Wireless Power Transmission With Arbitrary Received Power Allocation

Optimal Design of Multitarget Wireless Power Transmission With Arbitrary Received Power Allocation

Japanese Institutionalization and Global Standardization of Wireless Power Transmission, and Recently R&D Trend in Japan

Japanese Institutionalization and Global Standardization of Wireless Power Transmission, and Recently R&D Trend in Japan

Design and Analysis of Wireless Power Transmission (2X1) MIMO Antenna at 5G - Frequencies for Applications of Rectenna Circuits in Biomedical

This research presents the design and analysis of a 5G harvesting energy Circuit (MIMO-rectenna) to receive wireless power at Sub-6 frequencies (5.6 GHz) as a power source for some medical devices carried by a patient and moved from one place to another, whether they are diagnostic or therapeutic devices. This concept aims (MIMO-rectenna) to increase the likelihood of obtaining electricity from the ambient field by harvesting energy at 5G- frequencies. The tiny MIMO (2x1) antenna measuring 30 by 40 mm2 is the antenna portion of this rectenna. It has been built and tested to operate at Sub-6 frequency, or 5.6 GHz, for wireless power transmission applications related to 5G technology. The MIMO antenna has parameters of E = 4.4, h = 1.6 mm, and tand = 0.025 when printed on an FR4 substrate. A significant section of the antenna's rear was removed to carry out the broadband process, and the material's front side was composed of a series of circular slits. In this antenna, the parasitic approach was employed to decrease the mutual coupling between two ports by creating an inverted T with precise dimensions. The CST software 2024 was used to assist with the design and simulation results of this MIMO antenna. It was discovered through the simulation that the mutual coupling for these ports, 𝑆12and 𝑆21, is equal to -51.476 dB, and that the S-parameters, 𝑆11, 𝑆22, equal -22 dB. That is, there is very little signal loss while switching from the first port to the second and vice versa. This antenna's rectifier comprised an AC-to-DC conversion circuit, a DC filter, and an impedance-matching network. With the use of ADS software 2024, this rectenna's design and simulation results were completed. The greatest conversion efficiency of this rectenna at the frequency of 5.6 GHz is determined to be between 65 % and 65.01% for load resistance between 12 KΩ and 15 KΩ at an input power of 14 dBm.

Advances in EV wireless charging technology – A systematic review and future trends

Current advancements in wireless power transfer systems have improved the viability of enhancing the scope of the driving journey of an Electric Vehicle. This paper addresses the prime aspects of wireless charging infrastructure using a systematic approach, such as compensation topologies, power converter circuit design, and power transfer methods. The exclusive wireless charging track on the road minimizes the size of the battery device and the charging duration of energy storage during driving. The ability to transmit high power through a coil placed on the road to the Electric Vehicle requires an appropriate design for the complete wireless power transmission module. This paper also presents advancements in the domain of wireless technologies and recommends upcoming opportunities and future research trends.

A wireless, battery-free device for electrical neuromodulation of bladder contractions

Lower urinary tract dysfunction (LUTD) is a prevalent condition characterized by symptoms such as urinary frequency, urgency, incontinence, and difficulty in urination, which can significantly impair patient's quality of life and lead to severe physiological complications. Despite the availability of diverse treatment options, including pharmaceutical and behavioral therapies, these approaches are not without challenges. The objective of this study was to enhance treatment options for LUTD by developing a wireless, battery-free device for managing bladder contractions. We designed and validated a compact, fully implantable, battery-free pulse generator using the magnetic induction coupling mechanism of wireless power transmission. Weighing less than 0.2 g and with a volume of less than 0.1 cubic centimeters, this device enables precise stimulation of muscles or neurons at voltages ranging from 0 to 10 V. Wireless technology allows real-time adjustment of key stimulation parameters such as voltage, duration, frequency, pulse width, and pulse interval. Our findings demonstrate that the device effectively controlled bladder contractions in mice when used to stimulate the Major Pelvic Ganglion (MPG). Additionally, the device successfully managed micturition in mice with bilateral transection of the pudendal nerve. In conclusion, the development of this innovative wireless pulse generator provides a safer and more cost-effective alternative to conventional battery-powered neurostimulators for bladder control, addressing the limitations of such devices. We anticipate that this novel technology will play a pivotal role in the future of electrical stimulation therapies for voiding dysfunctions.

Multi-field coupling analysis of photovoltaic cells under long distance and multi-mode laser transmission

Most electronic devices are powered by electricity, and the transfer of energy to related electronic devices is a critical issue. Laser wireless power transmission (LWPT) has a broad prospect in the field of wireless energy transmission, such as distributed charging system (DLC), spacecraft sensor network, satellite-to-satellite communication and medium and long distance power transmission, ground to unmanned aerial vehicle (UAV), and so on. In this paper, a multi-field coupled model of LWPT system for laser transmission at medium and long distances is established. Through the existing LWPT experimental platform and test, the test obtained the correlation coefficient of the I-V relationship formula with the change of light intensity and temperature. On the basis of the modified parameters, the attenuation efficiency of laser power with transmission distance is calculated, and the heat transfer and electrical characteristics of photovoltaic cells are solved by finite element method. It is found that different atmospheric environment and laser transmission distance have obvious effects on the voltage, current and temperature variation of photovoltaic cells. The temperature of a photovoltaic cell has a huge impact on its output efficiency. The temperature can be controlled effectively by setting the laser interval of pulse mode reasonably. The cooling capacity of photovoltaic cells is the key to improve the electrical conversion efficiency of LWPT systems.

Enhancing PV receiver efficiency in laser wireless power transmission through square elliptic hyperboloid concentrator

AbstractLaser wireless energy transmission is a widely utilized method, yet its efficiency is constrained by a variety of factors. In order to improve the conversion efficiency of the receivers of the laser wireless power transmission (LWPT) system, the square elliptic hyperboloid (SEH) concentrating module designed for LWPT system receivers is developed. By analysing the I–V characteristic curves from the results of the experiments and employing non‐linear parameter regression, a corrected battery characteristic curve was derived within a specific laser irradiation range. On this basis, an optical–thermal–electric multi‐field coupling characteristic model was developed. The finite element method is used to simulate the multi‐field coupling characteristics and conversion efficiency of the receiving end under diverse working conditions (including different rotation angles and different divergence angles) of the concentrating photovoltaic module. Research shows: First, the larger the divergence half‐angle β of the laser beam, the more obvious the improvement of the effective optical efficiency of the system by the SEH concentrator. Second, the short‐circuit current and the maximum output power of the PV cell at the receiving end are significantly improved by the SEH concentrator, and the improvement effect is more obvious with the increase of the divergence angle and the rotation angle. Third, SEH concentrators did not significantly affect the fill factor of PV cells.

Sum-Rate Maximization for a Hybrid Precoding-Based Massive MIMO NOMA System with Simultaneous Wireless Information and Power Transmission

Non-orthogonal multiple access (NOMA) has emerged as a key enabling technology in the realm of millimeter-wave (mmWave) massive MIMO (mMIMO) systems for enhancing spectral efficiency (SE). Furthermore, it is believed that simultaneous wireless information and power transmission (SWIPT) will allow for the system’s energy efficiency (EE) to be maximised. The effectiveness of the mmWave mMIMO-NOMA system along with SWIPT has been examined in this article under multi-user (MU) scenarios. This paper’s major goal is to construct a low-complexity hybrid-precoder (HP) while taking into account the sub-connected (SC) architecture. The linear precoder is a computationally demanding technique as a result of the matrix inversion. The authors of this paper have suggested a symmetric sequential over-relaxation (SSOR) complex regularised zero-forcing (CRZF) linear precoder. The power distribution for the mmWave mMIMO-NOMA system and power splitting factors for SWIPT are jointly tuned to maximize the sum rate along with the suggested SSOR-CRZF precoder. In regards to complexity, SE, and EE, the SSOR-CRZF-HP surpasses conventional linear precoders.

Research on PV array reconstruction and Full-cycle maximum power point tracking technology of space solar power station

Space solar power station is an energy system that converts solar energy into electrical energy in the space environment and then transmits it to the space platform or ground using wireless power transmission technology. To improve the power generation and system efficiency of the space solar power station, an adaptive and reconfigurable photovoltaic array with multi-configuration is proposed, which can avoid large attenuation of the output power and efficiency of the photovoltaic array when the photovoltaic modules have a fault occurs or the receive different irradiation intensity. Then, according to the orbit area and light condition of the space solar power station, the operation mode are divided in detail. Furthermore, a novel full-cycle and multi-mode GMPPT (maximum power point tracking) strategy is proposed. Compared to the single mode MPPT, the control strategy has shorter response time, faster convergence and higher tracking accuracy. Through the above research, the output power and photoelectric conversion efficiency of space solar power station can be significantly improved.