Showing papers on "Electromagnetic coil published in 2022"
TL;DR: A design methodology to employ antiparallel windings to smooth the coupling coefficients variation over different positions by reducing the coupling coefficient at central positions and enhancing it at boundary positions is proposed.
Abstract: Free positioning wireless charging for consumer electronics allows the devices to be charged at arbitrary positions and angles to improve user experience. However, a user-initiated sudden movement of the device during charging can cause hazards due to the abrupt variation of the coupling coefficient. To solve this issue, the coupling coefficient variation at different positions should be mitigated, which is also good for the design and high-efficiency operation of power electronics converters. This article proposes a design methodology to employ antiparallel windings to smooth the coupling coefficient variation over different positions by reducing the coupling coefficient at central positions and enhancing it at boundary positions. Two optimization methods are proposed: turn-by-turn optimization and winding-by-winding optimization. A design flow is offered. The hexagonal coil is compared with the square coil and proved to achieve better performance than the latter. An experimental prototype is implemented to validate the effectiveness of the proposed design methodology.
46 citations
TL;DR: In this article , a superconducting magnetic levitation (maglev) magnetoelectric generator (SMMG) was proposed to convert mechanical impacts to electricity at its working temperature <90 K. The SMMG can charge a capacitor of 10 000 µF to 3.8 V with a continuous impact.
Abstract: Solar cells are conventionally used to harvest energy in outer space, but they are ineffective in dark locations. Here, it is shown that superconducting materials—which work best in cold environments, such as those found in outer space—provide a mechanism to harvest energy that does not require light. A superconducting magnetic levitation (maglev) magnetoelectric generator (SMMG) can convert mechanical impacts to electricity at its working temperature <90 K. The SMMG device consists of a permanent magnet, a conductive coil, and a superconducting layer (SL). Owing to the existence of the SL, the permanent magnet levitates over the SL and rapidly returns to an equilibrium height after being displaced by a mechanical impact. The impact changes the gap between the levitated magnet and the coil, resulting in a variation in magnetic flux that induces electrical current in the coil. Thus, the SMMG converts low‐frequency (<3.7 Hz) mechanical energy to electricity. The output maximum peak voltage, peak power, and peak power density of the SMMG are 4.3 V, 35 mW, and 17.8 W m−2, respectively, with a load resistance of 300 Ω. The SMMG can charge a capacitor of 10 000 µF to 3.8 V with a continuous impact, which is sufficient to power critical wireless communication. The superconductor works best in cold environments and therefore is well‐suited for providing electricity to sensors and communication devices in outer space, particularly in places where the sun may not reach.
36 citations
TL;DR: In this paper, a miniaturized split-phase half-turn transformer is demonstrated, which leverages the well-established parallelization benefit of employing multiple phases, as in a matrix transformer, with the dramatic reduction in copper loss associated with the relatively new Variable Inverter/Rectifier Transformer (VIRT) architecture.
Abstract: High step-down, high output current converters are required in many common and emerging applications, including data center server power supplies, point-of-load converters, and electric vehicle charging. Miniaturization is desirable but challenging owing to the high step-down transformer ubiquitously used in these converters. In this work, a miniaturized split-phase half-turn transformer is demonstrated, which leverages the well-established parallelization benefit of employing multiple phases, as in a matrix transformer, with the dramatic reduction in copper loss associated with the relatively new Variable Inverter/Rectifier Transformer (VIRT) architecture. While these techniques have been described in earlier studies, their combination has not been well explored. A detailed design procedure is described and is used to develop a 97.7% peak efficiency and 97.1% full-load efficiency prototype having a transformer that is 12%–36% smaller than best-in-class designs in the literature at the same power level while also being more efficient. This work showcases the miniaturization benefit of employing multiphase, fractional-turn transformers in high step-down, high output current applications and provides comprehensive guidance to designers interested in applying and extending these techniques.
31 citations
TL;DR: Compared with the conventional proportional-integral-derivative controller, simulation and experimental results are given to show the performance and robustness of dynamic wireless charging system by the proposed method.
Abstract: The dynamic wireless charging for electric vehicles (EVs) is considered an efficient and practical choice to extend the driving range and reduce battery pack size. However, the coupling coefficient between transmitter coils and receiver coil varies rapidly on a large scale during the EVs moving, so it deteriorates the charging performance of dynamic wireless power transfer in EVs, such as the discontinuous charging for the lithium-ion batteries in EVs. Moreover, the charging power and efficiency of the system can also be affected. To solve these issues, a dc–dc converter is added to cascade on the receiver side to improve the output power and efficiency of the system. Furthermore, the passivity-based proportional-integral control is designed for the dc–dc on the receiver side of dynamic wireless charging system to improve the performance against the rapidly changing coupling coefficient. Finally, compared with the conventional proportional-integral-derivative controller, simulation and experimental results are given to show the performance and robustness of dynamic wireless charging system by the proposed method.
27 citations
27 citations
TL;DR: In this paper , a cost-effective dynamic wireless power transfer (DWPT) system for efficient and stable output power charging of autonomous moving equipment is realized based on a low-cost segmented configuration and a flexible operating strategy.
Abstract: This article presents a cost-effective dynamic wireless power transfer (DWPT) system for efficient and stable output power charging of autonomous moving equipment. The proposed system is realized based on a low-cost segmented configuration and a flexible operating strategy. Specifically, the configuration is a combination of a dynamic T -series/series topology and extended transmitter (Tx) coils. The topology eliminates the cross-coupling impact of adjacent Tx coils and tunes the dynamic circuits at resonance. It makes the switching circuits equivalent to a unified analytical model for simplified control, which reduces the cost of inverter, decoupling, compensation, and position detection in the DWPT. The extended Tx coil with a simplified structure, which is obtained from winding coupling characteristics and a finite-element analysis based algorithm, is proposed to improve the moving misalignment tolerance, thereby reducing the number of Tx segments. An operating principle with three modes behind the proposed strategy is designed to fully utilize the efficient coupling area of individual Tx segment and improve the efficiency in the transition region from one segment to the other one. The operating parameters including the transition and compensation are obtained based on the topology and its operating principles. Position detection and power regulation methods are developed and embedded in the system control to configure/coordinate the segmented coils as the strategy and mitigate power fluctuation in the transition region. The performance and effectiveness of the proposed cost-effective DWPT system are evaluated based on experimental results on a scaled-down prototype.
26 citations
TL;DR: In this article , the state-of-the-art printing of soft magnetic, hard magnetic, and electrically conductive materials was investigated to evaluate the maturity of each material type for integration into electrical machine (EM) construction.
Abstract: Metal additive manufacturing (AM) technology is maturing. Although currently slower and less reliable than traditional production methods, AM systems shine when producing parts with unconventional topologies or in small quantities. Like countless other research communities, the electrical machine (EM) research community has shifted considerable efforts towards integrating AM systems into the EM production cycle to implement more powerful and efficient topology optimized (TO) next-generation EMs. In this paper, the state-of-the-art printing of soft magnetic, hard magnetic, and electrically conductive materials was investigated to evaluate the maturity of each material type for integration into EM construction. The highest maturity was identified for AM pure copper, showing characteristics equivalent to commercial high purity copper. In contrast, AM permanent magnets were the least mature: suffering from low power density and limited magnetization capacities. Printed soft magnetic steels were characterized as halfway in-between: on one side showing equivalent DC magnetic properties to conventional non-oriented steels, but on the other – suffering from high eddy current losses in AC applications. Based on the study's findings, it would appear that the emergence of additively manufactured EMs is only a matter of time. We predict a dramatic increase in the printing of prototype TO components within the next few years, focusing most likely on TO machine windings, heat exchangers, and synchronous rotors.
26 citations
TL;DR: In this paper , the authors proposed a design methodology to employ antiparallel windings to smooth the coupling coefficient variation over different positions by reducing coupling coefficient at central positions and enhancing it at boundary positions.
Abstract: Free positioning wireless charging for consumer electronics allows the devices to be charged at arbitrary positions and angles to improve user experience. However, a user-initiated sudden movement of the device during charging can cause hazards due to the abrupt variation of the coupling coefficient. To solve this issue, the coupling coefficient variation at different positions should be mitigated, which is also good for the design and high-efficiency operation of power electronics converters. This article proposes a design methodology to employ antiparallel windings to smooth the coupling coefficient variation over different positions by reducing the coupling coefficient at central positions and enhancing it at boundary positions. Two optimization methods are proposed: turn-by-turn optimization and winding-by-winding optimization. A design flow is offered. The hexagonal coil is compared with the square coil and proved to achieve better performance than the latter. An experimental prototype is implemented to validate the effectiveness of the proposed design methodology.
26 citations
TL;DR: In this paper , the authors present an overview of diagnostic methods and techniques for permanent magnet synchronous motors (PMSM) drives and present some development trends and challenges related to the development of diagnostics and fault-tolerant control of PMSM drives.
Abstract: The issues of monitoring and fault diagnosis of drives with permanent magnet synchronous motors (PMSM) are currently very topical due to the increasing use of these drives in safety-critical devices. Every year, more and more articles on this subject are published. Therefore, the aim of this article is to update the overview of diagnostic methods and techniques for PMSM drives. Each of the main chapters of the article focuses on a specific element of the drive system (motor, power converter, measuring sensors), with particular emphasis on the components of the motor (stator windings, magnets, bearings, rotor). The main sections on PMSM fault diagnosis are divided according to the type of methods used to obtain the symptoms of the damage. In addition, a review of methods using the analysis of control structure signals for the diagnosis of damage to a vector-controlled motor is presented, as well as the latest achievements of researchers in the field of shallow and deep neural networks for the detection and classification of PMSM drives failures. Based on the presented literature analyses, some development trends and challenges related to the development of diagnostics and fault-tolerant control of PMSM drives are discussed in the conclusion part.
23 citations
TL;DR: In this article, a serrated wire coil (SWC) was used as a turbulent generator to enhance the heat transfer in heat exchangers, and the experimental results of heat transfer and friction loss were presented as dimensionless parameters, Nusselt number (Nu) and friction factors (f), respectively.
23 citations
TL;DR: In this paper , a genetic algorithm was used to optimize the side lengths of the transmitting and receiving coils of the Tx and Rx coils, respectively, to achieve better coupling performance in different misalignment situations.
Abstract: The misalignment between the transmitting (Tx) coil and the receiving (Rx) coil is an urgent problem in the drone charging system using wireless power transfer technology. The coupling coefficient is so low when the resonance coils is not aligned, which degrades the drone wireless charging performance. In this article, the optimization processes of the coupling mechanism are presented in detail. First, we illustrate the great superiority of unequally spaced Tx coil, compared with traditional uniformly spaced one. Then, a genetic algorithm to optimize the side lengths of the Tx coils is highlighted by discussing the main design considerations and methods in a comprehensive manner. Furthermore, the Rx coil with varying radius size per turn is proposed in terms of the distribution of magnetic field generated by the optimized Tx coil. Experimental results show that the optimized coils have better coupling performance due to small mutual inductance change under the condition of misalignment. Power transfer efficiencies in different misalignment situations are measured and the best power transfer efficiency improvement achieved by the proposed system can reach 56.23% in contrast with traditional coils. This drone charging system can transfer a maximum power of 100 W with the remarkable transfer efficiency of 92.41%.
TL;DR: A novel dc–dc light-emitting diode driver employing an interleaved converter is proposed and analyzed, and the circuit efficiency as high as 95.0% is measured and satisfactory performance has verified the feasibility of the proposed converter.
Abstract: In this article, a novel dc–dc light-emitting diode driver employing an interleaved converter is proposed and analyzed. The circuit topology mainly consists of two parallel buck–boost converters. A coupled inductor, which is composed of a magnetic core and two windings, is used to replace the energy storage inductors of the two buck–boost converters. This not only does not add any components, but also saves a magnetic core. The buck–boost converters are designed to operate near boundary conduction mode. Due to the characteristics of magnetic flux balance, the magnetic-excited current can be converted between the windings of the coupled inductor. By using the magnetic-excited current to release the charge stored in the parasitic capacitors of the active switches, these switches can fulfill zero-voltage switching on (ZVS) without the use of any auxiliary switches, active clamping circuits, or snubber circuits. Moreover, the freewheel diodes of both buck–boost converters can achieve zero-current switching off (ZCS). The steady-state analyses for different operation modes are provided, and the mathematical equations for designing circuit components are conducted. Finally, a 200-W prototype circuit was built and tested to verify the analytical predictions. According to the experimental results, all the semiconductor devices are operated at either ZVS or ZCS, and the circuit efficiency as high as 95.0% is measured. Satisfactory performance has verified the feasibility of the proposed converter.
TL;DR: In this article , a comprehensive review for different winding topologies is presented, showing a high level of maturity of additive manufacturing in the production of the machine windings, and different challenges facing the design of the windings are introduced including the AC high frequency losses, thermal management, mechanical and acoustic problems, insulation aging, automated production, and winding manufacturability.
Abstract: The ever-increasing demand for higher-power dense electrical machines has resulted in different electrical, mechanical, and thermal stresses, which can eventually cause machine failure. For this reason, the management of stresses and losses must be thoughtfully investigated to have a highly reliable electrical machine. The literature agrees that winding losses are the dominant loss mechanism in many electrical machines. However, statements vary on how to mitigate these losses along with the aforementioned stresses. To avoid winding failure, a study of the various winding topologies would allow for a better consideration of the challenges and limitations in the performance of different electrical machines. To this aim, this paper introduces a comprehensive review for different winding topologies. Many reported cases in the literature are summarized and compared. Moreover, the utilization of additive manufacturing (AM) in the production of the machine windings is presented, showing a high level of maturity of this emerging technology. Finally, different challenges facing the design of machine windings are introduced including the AC high frequency losses, thermal management, mechanical and acoustic problems, insulation aging, automated production, and winding manufacturability.
TL;DR: In this paper, a multicoupling LCC-compensated method for EVDWC system based on an integrated magnetic coupler to suppress the power fluctuation is proposed, where the main advantage of the proposed method is to realize compensation inductance using coupling coils, thereby adding two cross-couplings.
Abstract: In the electric vehicle dynamic wireless charging (EVDWC) system, when the electric vehicle (EV) drives from one track to the next, it will produce output power fluctuation. This article proposes a multicoupling LCC-compensated method for EVDWC system based on an integrated magnetic coupler to suppress the power fluctuation. The magnetic coupler includes three couplings. The first coupling is between the main coils. The second coupling is between the adjacent compensation inductor coils integrated into main coils. The third coupling is between the primary compensation inductor coils and the secondary compensation inductor coil. The main coils are unipolar and the compensation inductor coils are in a double D structure. The parameter matching rules and optimized design process considering the additional cross-couplings are given. The main advantage of the proposed method is to realize compensation inductance using coupling coils, thereby adding two cross-couplings, and to suppress output power fluctuation based on system normal operation without adding new components. A prototype is designed and implemented to validate the proposed magnetic coupler and parameter design rules. Experimental results show that the output power fluctuation is within ±4% during dynamic charging at a power level of 12 kW, and the maximum efficiency reaches 92.3%.
TL;DR: In this paper , a serrated wire coil (SWC) was used as a turbulent generator to enhance the heat transfer in heat exchangers under isothermal-flux conditions.
TL;DR: The JT-60SA tokamak was completed on schedule in March 2020 as discussed by the authors , and all the main components satisfied technical requirements, including dimensional accuracy and functional performances, including plasma heating systems and diagnostics.
Abstract: Abstract Construction of the JT-60SA tokamak was completed on schedule in March 2020. Manufacture and assembly of all the main tokamak components satisfied technical requirements, including dimensional accuracy and functional performances. Development of the plasma heating systems and diagnostics have also progressed, including the demonstration of the favourable electron cyclotron range of frequency (ECRF) transmission at multiple frequencies and the achievement of long sustainment of a high-energy intense negative ion beam. Development of all the tokamak operation control systems has been completed, together with an improved plasma equilibrium control scheme suitable for superconducting tokamaks including ITER. For preparation of the tokamak operation, plasma discharge scenarios have been established using this advanced equilibrium controller. Individual commissioning of the cryogenic system and the power supply system confirmed that these systems satisfy design requirements including operational schemes contributing directly to ITER, such as active control of heat load fluctuation of the cryoplant, which is essential for dynamic operation in superconducting tokamaks. The integrated commissioning (IC) is started by vacuum pumping of the vacuum vessel and cryostat, and then moved to cool-down of the tokamak and coil excitation tests. Transition to the super-conducting state was confirmed for all the TF, EF and CS coils. The TF coil current successfully reached 25.7 kA, which is the nominal operating current of the TF coil. For this nominal toroidal field of 2.25 T, ECRF was applied and an ECRF plasma was created. The IC was, however, suspended by an incident of over current of one of the superconducting equilibrium field coil and He leakage caused by insufficient voltage holding capability at a terminal joint of the coil. The unique importance of JT-60SA for H-mode and high- β steady-state plasma research has been confirmed using advanced integrated modellings. These experiences of assembly, IC and plasma operation of JT-60SA contribute to ITER risk mitigation and efficient implementation of ITER operation.
TL;DR: The European DEMO Magnet System as mentioned in this paper has successfully passed the DEMO plant-level gate review in 2020, and the main design input parameters originate from the so-called DEMO 2018 baseline, which was produced using the PROCESS systems code.
TL;DR: In this article , a planar 5-coil mTMS transducer was developed to allow controlling the maximum of the induced electric field (E-field) within a cortical region approximately 30 mm in diameter.
TL;DR: In this article, a planar 5-coil mTMS transducer was designed and manufactured to allow controlling the maximum of the induced electric field (E-field) within a cortical region approximately 30mm in diameter.
TL;DR: In this paper , a torsional-spring-shaped coil of liquid metal wound around an elastomeric tubing and equipped with a tiny piece of a magnetic ring was used to detect human motion.
01 Sep 2022
TL;DR: In this paper , a comprehensive design approach of hairpin winding layouts is presented, in which the flexibility and limitation of end-winding patterns are thoroughly investigated in terms of basic pin connections, special jumpers, transposition, parallel branches, terminal positions, phase shift, winding pitches, as well as slot-pole combinations.
Abstract: The rapidly increasing demand on power density levels of electric vehicle (EV) drive systems is pushing the boundaries of traction motor performance. Hairpin windings are becoming a popular option for EV motors due to their reduced dc losses and improved heat dissipation capability when compared to traditional random windings. In this article, a comprehensive design approach of hairpin winding layouts is first presented. The flexibility and limitation of end-winding patterns are thoroughly investigated in terms of basic pin connections, special jumpers, transposition, parallel branches, terminal positions, phase shift, winding pitches, as well as slot–pole combinations. To address the challenge of much reduced practical layout options with increased slot number per pole per phase, two novel hairpin winding designs are proposed. A 160-kW, 18 000-r/min permanent magnet (PM) traction motor featuring the new winding layout with 54-slot, 6-pole is developed using a multidomain design platform, which puts special focus on the conductor size optimization. The advantages of the designed motor are clearly revealed by comparison with the more traditional 48-slot, 8-pole counterpart. Finally, a corresponding stator prototype with the proposed hairpin winding is built to validate its manufacturability.
TL;DR: This article optimizes the parameters and shape of the cubic-magnetic coupler for inductive power transfer (IPT) system, which has huge application potential in the charging field of moving targets.
Abstract: This article proposes a kind of cubic-magnetic coupler (CMC) for inductive power transfer (IPT) system, which has huge application potential in the charging field of moving targets. The CMC can still maintain sufficient coupling coefficient when used for long-distance wireless power transfer, it also has great capability of misalignment tolerance. Distance-to-diameter ratio (DDR) is defined to eliminate the impact of coil size and make the comparison between different couplers fairer and easier. This article optimizes the parameters and shape of the CMC. Then, the proposed coupler is compared with several existing couplers employed in long-distance IPT systems. Double-sided LCC compensation topology is chosen to limit the current flowing through the coupling coils. A CMC with an outer size of 180×180×180 mm3 was made, based on which an IPT prototype was built. The superiorities of the proposed coupler were verified by a series of experiments. When the DDR equals 3, the coupling coefficient of the CMC is 0.00985, and the maximum dc–dc and ac–ac efficiencies are 64.9% and 72.8%, respectively.
TL;DR: In this paper, an extendable planar Tx-coil array architecture was proposed to achieve high spatial freedom of power transfer and compact and lightweight designs for MHz WPT systems.
Abstract: Wireless power transfer (WPT) systems operating at several MHz are known to be advantageous for realizing high spatial freedom of power transfer and compact and lightweight designs. The combined use of multiple transmitting (Tx) coils for magnetic field shaping is expected to further increase the spatial freedom. This article studies an extendable planar Tx-coil array architecture. This architecture provides new conveniences for the MHz WPT systems to efficiently charge devices in 3D space. Time-domain and phasor-domain modelings are carried out in turn to analyze the magnetic field shaping effect under the current phase shift modulation of the Tx coils. An overlap design of the Tx-coil layout is also developed to minimize the cross coupling between the coils, which reduces the interference between Tx coils. Finally, the above concepts are experimentally implemented. The results clearly demonstrate the new advantages of the planar Tx-coil array-based magnetic field shaping, in terms of spatial freedom of the power transfer, efficiency, and output power capability, when charging receivers with six-degrees-of-freedom positions and orientations in 3D space. For instance, a perpendicular receiver in the center of the Tx-coil array can be charged with 82% dc–dc efficiency and 45 W, which is difficult for a conventional single Tx-coil solution.
TL;DR: In this article , a novel material used in this SLA 3D printed electromagnetic nanocomposite microactuator, which has advantages in costs and time saving by a simplified fabrication process and minimum chances of human interactions, is presented.
TL;DR: In this article , a dc-dc converter is added to cascade on the receiver side to improve the output power and efficiency of the system, and a passivity-based proportional-integral control is designed for the dc −dc on the receiving side of dynamic wireless charging system to improve performance against the rapidly changing coupling coefficient.
Abstract: The dynamic wireless charging for electric vehicles (EVs) is considered an efficient and practical choice to extend the driving range and reduce battery pack size. However, the coupling coefficient between transmitter coils and receiver coil varies rapidly on a large scale during the EVs moving, so it deteriorates the charging performance of dynamic wireless power transfer in EVs, such as the discontinuous charging for the lithium-ion batteries in EVs. Moreover, the charging power and efficiency of the system can also be affected. To solve these issues, a dc–dc converter is added to cascade on the receiver side to improve the output power and efficiency of the system. Furthermore, the passivity-based proportional-integral control is designed for the dc–dc on the receiver side of dynamic wireless charging system to improve the performance against the rapidly changing coupling coefficient. Finally, compared with the conventional proportional-integral-derivative controller, simulation and experimental results are given to show the performance and robustness of dynamic wireless charging system by the proposed method.
TL;DR: In this paper , a dc-dc light-emitting diode driver employing an interleaved converter is proposed and analyzed, and the circuit topology mainly consists of two parallel buck-boost converters.
Abstract: In this article, a novel dc–dc light-emitting diode driver employing an interleaved converter is proposed and analyzed. The circuit topology mainly consists of two parallel buck–boost converters. A coupled inductor, which is composed of a magnetic core and two windings, is used to replace the energy storage inductors of the two buck–boost converters. This not only does not add any components, but also saves a magnetic core. The buck–boost converters are designed to operate near boundary conduction mode. Due to the characteristics of magnetic flux balance, the magnetic-excited current can be converted between the windings of the coupled inductor. By using the magnetic-excited current to release the charge stored in the parasitic capacitors of the active switches, these switches can fulfill zero-voltage switching on (ZVS) without the use of any auxiliary switches, active clamping circuits, or snubber circuits. Moreover, the freewheel diodes of both buck–boost converters can achieve zero-current switching off (ZCS). The steady-state analyses for different operation modes are provided, and the mathematical equations for designing circuit components are conducted. Finally, a 200-W prototype circuit was built and tested to verify the analytical predictions. According to the experimental results, all the semiconductor devices are operated at either ZVS or ZCS, and the circuit efficiency as high as 95.0% is measured. Satisfactory performance has verified the feasibility of the proposed converter.
TL;DR: In this paper , a new IPT system with dual transmitters and dual receivers with integrated decoupling coils is introduced, where the proposed decoupled coils are also taking part in power transmission.
Abstract: To ensure the effectiveness of the inductive power transfer (IPT) systems for high-power applications, multiple coils are being used. However, cross couplings among the same-side coils reduce the efficiency of the system. Thus, decoupling coils are commonly used to mitigate the same-side couplings in a multiple-transmitter and multiple-receiver system. The decoupling coils are either used outside of the main coils or concentric with the main coils. In both cases, these decoupling coils do not take part in the power transmission and have some adverse effects on the system performance. In this article, a new IPT system with dual transmitters and dual receivers with integrated decoupling coils is introduced. Besides mitigating the mutual inductances of the same-side coils, the proposed decoupling coils are also taking part in power transmission. In addition, the proposed coils also have good misalignment performance. A 3-D finite-element analysis tool ANSYS MAXWELL is used to investigate the proposed magnetic coupler. A scaled-down experimental setup is used to verify the feasibility of the proposed structure. The maximum dc–dc efficiency of this system is 93.14% while delivering 700 W to the load with a 200-mm air gap. Besides, zero-voltage switching is also achieved in the experiment, which suggests that the proposed system can be an effective solution for the current drawbacks of the multiple-transmitter and multiple-receiver system.
TL;DR: In this paper , the authors presented a novel method to improve the performance of the dynamic wireless recharge system, where receiver coils have been added to maximize charging power by offering a dynamic mathematical model that can describe and measure source-to-vehicle power transmission even though it is in motion.
TL;DR: Faraday coil transfer-power measurement (FC-TPM) employs non-contact, open-circuited sense coils to measure the electromagnetic field from WPT and calculates the real power propagating through the air gap between the transmitter and receiver coils.
Abstract: Wireless power transfer (WPT) is emerging as the preeminent way to charge electric vehicles, but there appears to be no fair way to measure the power transfer. In this article, Faraday coil transfer-power measurement (FC-TPM) is presented. FC-TPM employs non-contact, open-circuited sense coils to measure the electromagnetic field from WPT and calculates the real power propagating through the air gap between the transmitter and receiver coils. What is measured is the real electromagnetic power, representing the pure dispensation of energy that unambiguously demarcates the losses on either side. FC-TPM was demonstrated to be 0.1% accurate in hardware over an Rx coil misalignment of up to 10 cm using a 1-kW WPT system. Fair metering incentivizes businesses and individuals to make choices that conserve energy and advance technology by providing more information and by properly assigning the financial loss. This article is accompanied by a video highlighting the essential contributions of this article.
TL;DR: In this article , a comprehensive review has been performed on the history of the evolution, working principles and phenomena, design considerations, control methods and health issues of IPT systems, especially those based on EV charging.
Abstract: Nowadays, Wireless Power Transfer (WPT) technology is receiving more attention in the automotive sector, introducing a safe, flexible and promising alternative to the standard battery chargers. Considering these advantages, charging electric vehicle (EV) batteries using the WPT method can be an important alternative to plug-in charging systems. This paper focuses on the Inductive Power Transfer (IPT) method, which is based on the magnetic coupling of coils exchanging power from a stationary primary unit to a secondary system onboard the EV. A comprehensive review has been performed on the history of the evolution, working principles and phenomena, design considerations, control methods and health issues of IPT systems, especially those based on EV charging. In particular, the coil design, operating frequency selection, efficiency values and the preferred compensation topologies in the literature have been discussed. The published guidelines and reports that have studied the effects of WPT systems on human health are also given. In addition, suggested methods in the literature for protection from exposure are discussed. The control section gives the common charging control techniques and focuses on the constant current-constant voltage (CC-CV) approach, which is usually used for EV battery chargers.