Inductive Coupling Research Articles

Design and Implementation of a Wireless Power Transfer System for Electric Vehicles

Wireless power transfer (WPT) systems, which have been around for decades, have recently become very popular with the widespread use of electric vehicles (EVs). In this study, an inductive coupling WPT system with a series–series compensation topology was designed and implemented for use in EVs. Initially, a 3D Maxwell (ANSYS Electromagnetics Suite 18) model of the system was generated. The impact of individual parameters on the coupling coefficient was analyzed through systematic variations in each parameter’s values. As a result, a system with a higher coupling coefficient was obtained. Using this system, three distinct load cases were investigated for their efficiency in the Simplorer (ANSYS Electromagnetics Suite 18) circuit. Subsequently, a prototype of the system was constructed, and the experimental results were compared with the model’s results. This study shows that both the output power and the efficiency of the system increase as the load resistance increases. The results obtained in this study are anticipated to offer valuable insights for the enhancement of WPT system design.

Evaluation of the Inductive Coupling between Coplanar Concentric Coils in the Presence of the Ground

An analytical approach is presented that allows deriving an exact series-form representation for the flux linkage between two physically large concentric circular coils located on a lossy soil. The expression comes from a three-step analytical procedure. First, the integral expression for the flux linkage is converted into a double integral consisting of a finite and a semi-infinite integral. Next, the semi-infinite integral is recognized to be a well-known tabulated Sommerfeld integral, which may be analytically evaluated straightforwardly. Finally, applying Lommel’s expansion allows rewriting the remaining finite integral as a sum of elementary integrals amenable to analytical evaluation. As a result, the flux linkage between the two coils is given as a sum of spherical Hankel functions of the wavenumber in the air and in the ground, multiplied by a coefficient depending on the geometrical dimensions of the coils. The accuracy and robustness of the proposed formulation is tested by comparing its outcomes with those generated by numerical integration of the complete integral representation for the flux linkage and with the results provided by previous analytical approaches to the same problem. It is found that the use of the derived expression for the inductance makes it possible to obtain significant time savings as compared to numerical quadrature schemes.

A Soft-Switched High-Gain Interleaved DC–DC Converter with Coupled Inductors for Renewable Energy Systems

A Soft-Switched High-Gain Interleaved DC–DC Converter with Coupled Inductors for Renewable Energy Systems

Recent Advances in Implantable Neural Interfaces for Multimodal Electrical Neuromodulation.

Electrical neuromodulation plays a pivotal role in enhancing patient outcomes among individuals suffering from neurological disorders. Implantable neural interfaces are vital components of the electrical neuromodulation system to ensure desirable performance; However, conventional devices are limited to a single function and are constructed with bulky and rigid materials, which often leads to mechanical incompatibility with soft tissue and an inability to adapt to the dynamic and complex 3D structures of biological systems. In addition, current implantable neural interfaces utilized in clinical settings primarily rely on wire-based techniques, which are associated with complications such as increased risk of infection, limited positioning options, and movement restrictions. Here, the state-of-art applications of electrical neuromodulation are presented. Material schemes and device structures that can be employed to develop robust and multifunctional neural interfaces, including flexibility, stretchability, biodegradability, self-healing, self-rolling, or morphing are discussed. Furthermore, multimodal wireless neuromodulation techniques, including optoelectronics, mechano-electrics, magnetoelectrics, inductive coupling, and electrochemically based self-powered devices are reviewed. In the end, future perspectives are given.

Study on the inductively coupled high rate system and long-distance transmission

The inductively coupled transmission chain can carry multiple Marine sensors, which is an important means to obtain Marine data, but the current transmission rate of inductively coupled data is low, which can not meet the needs of future Marine data transmission. The induction coupling system designed in this paper adopts the structure of double magnetic loop and a double-winding, and adopts the new single frequency different code algorithm to realize the data transmission rate of 150kbps. Different water environments were set up in the laboratory for testing, and the lower bit error rate was found in the water environment with the ion concentration of 10%-35%, which met the requirements of inductive coupling data transmission in a multi-water environment. It is of great significance to establish the research of underwater inductively coupled long-distance transmission for the subsequent design of a new inductively coupled transmission chain and the improvement of the data transmission rate.

Theoretical and Practical Analysis of MIMO Simultaneous Wireless Information and Power Transfer Over Inductively Coupled Circuits

The number of wireless devices continues to increase, and this growth will be further fueled by the Internet of Things (IoT). There is an urgent need to develop new techniques to both wirelessly transfer power to and communicate with these devices. Recently, inductive power transfer has gained much attention as a potentially efficient wireless powering solution for short and medium distance charging scenarios. In this paper, we consider multiple-input multiple-output (MIMO) simultaneous wireless information and power transfer (SWIPT) using inductive coupling. While an analysis of SWIPT requires a model that correctly captures transmit power, harvested power, and information capacity, the vast majority of previous studies have overlooked the relationship between the mathematical signal representations and the real-world physical quantities. To overcome this challenge, we propose a framework in which signals and channels are represented by traveling waves and scattering parameters. The optimal covariance matrices of the transmit traveling waves are derived for three different working scenarios. We propose a simple estimation procedure to determine unknown scattering parameters and noise distribution. The rate-energy regions and the magnetic field strengths are computed for two inductively-coupled MIMO models based on the finite element method.

New Coupled-Inductor High-Gain DC/DC Converter With Bipolar Outputs

This paper presents a new bipolar step-up DC/DC converter with the capability of decreasing the input current ripple for renewable energy applications. Two power switches with the simultaneous operation are used in the proposed converter. The suggested topology can provide positive and negative output voltages in a quadratic form with the same and different voltage levels and common ground. The bipolar outputs of the presented topology can be varied independently using the duty cycle and tuning the turn ratio of the coupled inductor (CI). Moreover, the maximum voltage stress across the switching components is much lower than the output voltage. This topology operates under soft-switching conditions for the second switch and all diodes. The steady-state and the main operating equations of the converter are also derived. Finally, a 210 W prototype with 110 V, -110 V, and 220 V output voltages is implemented to justify the theoretical analysis and performance operation of the proposed converter.

A light Darwin implementation of Maxwell’s equations to quantify resistive, inductive, and capacitive couplings in windings

High operating frequency is an enabler of high key performance indicators, such as increased power density, in electrical machines. The latter enhances the cross-coupling of resistive–inductive–capacitive phenomena in windings, which may lead to significant loss in performance and reliability. The full-wave Maxwell’s equations can be employed to characterize this coupling. To address the frequency instability that arises as a result, a simplification known as the Darwin formulation can be employed, where the wave propagation effects are neglected. Still, this modification is prone to ill-conditioned systems that necessitate intricate pre-conditioning and gauging steps. To overcome these limitations, a fast 2D formulation is derived, which preserves the current continuity conservation along the model depth. This implementation is validated experimentally on a laboratory-scale medium-frequency transformer. The computed impedances for the open- and short-circuit modes of the transformer are validated using measurements and compared with the multi-conductor transmission line model that is widely adopted for the analysis mentioned above. The developed formulation demonstrates a high accuracy and outstanding frequency stability in a wide frequency range, becoming an efficient and computationally light method to investigate the interconnected resistive, inductive, and capacitive effects in windings.

Optimized Air-Gap Configuration for an Integrated Coupled Inductor With Lower Height and Reduced Core/Winding Losses

Optimized Air-Gap Configuration for an Integrated Coupled Inductor With Lower Height and Reduced Core/Winding Losses

Si/WBG Hybrid Half-Bridge Converter Using Coupled Inductors for Power Quality Improvement and Control Simplification

Si/WBG Hybrid Half-Bridge Converter Using Coupled Inductors for Power Quality Improvement and Control Simplification

Design of Coupled Inductor Using Powder Core with Concentrated Air Gap in Multiphase Operation

Design of Coupled Inductor Using Powder Core with Concentrated Air Gap in Multiphase Operation

Current Collector Health Monitoring of LRT Trains Powered by Three-Phase AC Power Rail Based on Inductive Coupling Method

Current Collector Health Monitoring of LRT Trains Powered by Three-Phase AC Power Rail Based on Inductive Coupling Method

Wideband On-Chip Filter With High Selectivity and Reduced Size by Single TV Inductive Coupling

Wideband On-Chip Filter With High Selectivity and Reduced Size by Single TV Inductive Coupling

Gathering Evidence to Leverage Musculoskeletal Magnetic Stimulation Towards Clinical Applicability

Musculoskeletal disorders are among the main causes of disease‐associated disability. Moreover, the incidence and prevalence of osteoporosis and osteoarthritis, as well as the risk of bone fractures and the need for joint replacements, are expected to increase with longer life expectancy. New approaches based on electromagnetic stimulation have been developed, aiming to shorten bone healing time, attenuate osteoporosis and osteoarthritis, and increase implants' osseointegration. Inductive coupling (IC), a non‐invasive methodology to deliver magnetic stimuli, has reached clinical trials and some clinical practices but is not yet considered a standard procedure. Indeed, its feasibility in clinical use is still under discussion, and optimal stimulation parameters are fairly undefined. This comprehensive review describes the research trends and applicability of IC‐based therapeutics for musculoskeletal disorders, and starts identifying top‐performing magnetic stimulation parameters. Insights into the magnetic stimuli setups that promote osteogenesis are provided, based on pre‐clinical and clinical evidence from 117 in vivo studies in animal models and human patients. Potential cellular and molecular biomechanisms mediating IC‐induced effects on osteoblasts and osteoclasts are also explored. The transversal knowledge herein delivered will hopefully support innovative designs and medical devices that will implement IC stimulation as a clinical standard and effective therapeutic for musculoskeletal disorders.

On the Design of a Stepped Mixed Signal Transmission Line with Defected Microstrip Structure for High-Frequency PCB Traces

The paper addresses the challenge of crosstalk in neighboring paths on PCBs, emphasizing its growing importance with the advancement of electronic circuits in terms of speed and frequency. The proposed solution involves the introduction of a novel W-shaped Defected Microstrip Structure (DMS) on a step-shaped coupled transmission lines to mitigate near-end crosstalk (NEXT) and far-end crosstalk (FEXT) using mixed signal input. A novel W-shaped defective microstrip structure (DMS) that is etched on step-shaped coupled transmission lines. The proposed technique focuses on minimizing the electromagnetic coupling strength with a minimum spacing of one time the width of the trace. It optimizes the ratio of capacitive coupling and inductive coupling between the coupled microstrip transmission lines to improve crosstalk. The frequency domain simulation, conducted using Computer Simulation Technology (CST), indicates promising results. The insertion loss (|S21|), near-end crosstalk (|S31|), and far-end crosstalk (|S41|) of the suggested structure are reported as 1.425dB, <25dB, and <25dB, respectively, over the frequency range of 0 to 10 GHz. Eye diagram characterizations are done and measured in terms of eye height, eye width, jitter and data rate are reported as 0.942V, 695.5ps, 6.69ps and 1.4Gbps respectively.

Development of Wireless Charging System Using Square-Circular Coupled Coils with Different Misalignments

Now a days, inductive power transfer (IPT) has gained a lot of attention from researchers as it has ease of use and realiability for electric vehicle (EV) battery charging systems. This paper examines the increasing attention from researchers towards inductive power transfer (IPT) as a means of charging electric vehicle (EV) batteries. This interest originates from the user-friendly characteristics and notable reliability associated with IPT. The evaluation of mutual inductance (MI) holds importance within the domain of Inductive Power Transfer (IPT) systems, as it serves a critical function in enabling effective power transfer. Therefore, it is essential to perform a comprehensive analysis of the mutual inductance between the two coils that are connected through inductive coupling. This study provides an examination of mutual inductance (MI) and efficiency within the context of interoperability conditions of interconnected coils. The transmitter coil is represented as a square structure, denoted as TxS, whereas the receiving coil is represented as a circular structure, denoted as RxC. Furthermore, the application of ferrite cores and steel chassis inclosures, in combination with coils, is utilised for the objective of electric vehicle (EV) battery charging. The magnetic induction (MI) analysis is performed by the utilisation of finite element method (FEM) simulation. The finite element method (FEM) simulation outcomes of the interconnected coils with misalignments, encompassing both non-core and steel chassis configurations, are juxtaposed with the corresponding empirical observations.

Dynamic cerebral blood flow assessment based on electromagnetic coupling sensing and image feature analysis.

Dynamic assessment of cerebral blood flow (CBF) is crucial for guiding personalized management and treatment strategies, and improving the prognosis of stroke. However, a safe, reliable, and effective method for dynamic CBF evaluation is currently lacking in clinical practice. In this study, we developed a CBF monitoring system utilizing electromagnetic coupling sensing (ECS). This system detects variations in brain conductivity and dielectric constant by identifying the resonant frequency (RF) in an equivalent circuit containing both magnetic induction and electrical coupling. We evaluated the performance of the system using a self-made physical model of blood vessel pulsation to test pulsatile CBF. Additionally, we recruited 29 healthy volunteers to monitor cerebral oxygen (CO), cerebral blood flow velocity (CBFV) data and RF data before and after caffeine consumption. We analyzed RF and CBFV trends during immediate responses to abnormal intracranial blood supply, induced by changes in vascular stiffness, and compared them with CO data. Furthermore, we explored a method of dynamically assessing the overall level of CBF by leveraging image feature analysis. Experimental testing substantiates that this system provides a detection range and depth enhanced by three to four times compared to conventional electromagnetic detection techniques, thereby comprehensively covering the principal intracranial blood supply areas. And the system effectively captures CBF responses under different intravascular pressure stimulations. In healthy volunteers, as cerebral vascular stiffness increases and CO decreases due to caffeine intake, the RF pulsation amplitude diminishes progressively. Upon extraction and selection of image features, widely used machine learning algorithms exhibit commendable performance in classifying overall CBF levels. These results highlight that our proposed methodology, predicated on ECS and image feature analysis, enables the capture of immediate responses of abnormal intracranial blood supply triggered by alterations in vascular stiffness. Moreover, it provides an accurate diagnosis of the overall CBF level under varying physiological conditions.

Characterization Of Resonant Coupled Inductor In A Wireless Power Transfer System

Wireless power transfer (WPT) has garnered significant interest as a potentially transformative technology in the energy sector, as it presents a novel approach to powering and charging devices. The functionality of this technology is predicated upon the utilization of electromagnetic coupling to facilitate the wireless transmission of energy between two entities. Despite the considerable potential, wireless power transfer (WPT) faces significant obstacles that restrict its practical feasibility. One notable challenge that arises is the decrease in power transfer efficiency as the distance between the transmitter and receiver increases. Moreover, the Wireless Power Transfer (WPT) technology is further limited by its reliance on accurate alignment between the transmitting source and the receiving device, thereby posing challenges for its practical implementation. The issues present substantial obstacles to the widespread commercialization of wireless power transfer (WPT). This study seeks to improve the efficacy of power transfer by optimizing the resonance frequency of the power transfer in response to the challenges. By systematically manipulating various parameters, including coil dimensions, input voltage levels, and operational frequency, a novel approach is proposed to enhance the efficiency of power transfer. The study additionally offers valuable insights regarding the correlation between the distance separating the coils and the efficiency of power transfer. The findings of this study offer a thorough empirical analysis and are supported by a strong theoretical framework, resulting in a substantial coefficient of determination (R² = 0.937118). This finding suggests that the linear regression model under consideration could account for approximately 93.7118 percent of the variability observed in the distance. The findings of this study establish a pathway towards enhanced and feasible wireless power technology, thereby establishing a robust basis for the prospective commercial implementation of wireless power transfer (WPT) systems.

Modeling, Analysis, and Winding Loss Calculation of Different Litz and Solid Wire on Coupled Inductor in DC–DC Cuk Converter for DCM

In this article, the coupled inductor is designed using a litz wire, an enameled litz wire, and a solid wire separately. All the coupled inductors wound with litz and solid wires are tested in a Cuk converter operated in DCM with a 25 kHz switching frequency for 15 W power, and winding losses of each wire, including proximity and skin effect loss, are calculated analytically without using any software, by using different techniques presented in literature, and the results are compared. Also, state-space modeling of the converter using a coupled inductor for DCM is derived as a contribution of the article because such a modeling is not derived for the Cuk converter in the literature. Thanks to the applications, inductor currents, switch voltage, input–output voltage, and output current are measured for coupled inductors with different wires. In addition, FEM simulation and co-simulation of all coupled inductors are realized, and the results obtained by applications are verified by them. Besides, it is shown that while the number of turns is the same, increasing the bundle of wires increases efficiency and inductance, reducing the window area and coupling coefficient.

Native Approach to Controlled-Z Gates in Inductively Coupled Fluxonium Qubits.

The fluxonium qubits have emerged as a promising platform for gate-based quantum information processing. However, their extraordinary protection against charge fluctuations comes at a cost: when coupled capacitively, the qubit-qubit interactions are restricted to XX interactions. Consequently, effective ZZ or XZ interactions are only constructed either by temporarily populating higher-energy states, or by exploiting perturbative effects under microwave driving. Instead, we propose and demonstrate an inductive coupling scheme, which offers a wide selection of native qubit-qubit interactions for fluxonium. In particular, we leverage a built-in, flux-controlled ZZ interaction to perform qubit entanglement. To combat the increased flux-noise-induced dephasing away from the flux-insensitive position, we use a continuous version of the dynamical decoupling scheme to perform noise filtering. Combining these, we demonstrate a 20ns controlled-z gate with a mean fidelity of 99.53%. More than confirming the efficacy of our gate scheme, this high-fidelity result also reveals a promising but rarely explored parameter space uniquely suitable for gate operations between fluxonium qubits.