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A nonwoven-based composite that can shield electromagnetic interference (EMI) in contemporary society was successfully fabricated by adhering graphene (GE) nanosheets to nonwoven fabric with polyvinylidene fluoride (PVDF) as the adhesive agent. A cyclic GE dispersion dipping-drying process produced nonwoven composites with increasing GE adsorption, which formed an ever more conductive network and led to improvement in EMI shielding performance. The bonding effects of PVDF between GE nanosheets and nonwoven framework were confirmed via ultrasonic vibration analysis and morphology observation. Composite shielding effects were evaluated in a wide incident frequency from 1 to 18 GHz, which revealed that the overall EMI shielding effectiveness was over 20 dB and this EMI shielding was absorption dominant. Such a composite possessed the potential to be used in household and industrial products for EMI shielding. [ABSTRACT FROM AUTHOR]

Due to the need of electromagnetic shielding materials for satellites, carbon/carbon (C/C) composites have become a research focus due to their excellent properties. In this study, the ultrahigh treatment temperature was raised from 2500 °C to 2700 °C and 3000 °C, and the influence of micromorphology on the mechanical and electromagnetic shielding properties of materials was explored with an innovative image recognition method. The porosity of the C/C composites increased with increasing heat treatment temperature, from 6.95% to 8.65% after 3000 °C. The density decreased, and the graphitization degree increased gradually, indicating an improvement in the texture order degree. For the compression properties of the material, the Z direction after treatment at 3000 °C maintained a high compressive strength of 171 MPa. The electromagnetic interference (EMI) shielding efficiency (SE) of the C/C composites, which is completely consistent with the trend of electrical conductivity, increased with increasing heat treatment temperature, and the EMI SE of the C/C composites reached ∼80 dB after 3000 °C. It was found that reflection was the dominant EMI shielding mechanism of C/C composite materials. By comparing the comprehensive data indexes of C/C composites with other materials, the composites are expected to be a new generation of satellites with electromagnetic shielding material. [Display omitted] [ABSTRACT FROM AUTHOR]

In this article, time diversity is used as an electromagnetic resilience technique in a triple modular redundant (TMR) communication channel that is subjected to a multiharmonic electromagnetic disturbance under semireverberant environments. This study is carried out in light of new electromagnetic interference (EMI) condition monitoring definitions, which provide a better insight into the actual state of the system. An explanation of the different fault mechanisms based on the new definitions is provided for a time diverse TMR system with a two-out-of-three majority voter and is compared with the previously used EMI condition monitoring definitions. The new definitions provide a better understanding on how to interpret the results of an EMI detector or an EMI corrector by keeping in consideration the safety and availability aspects of system. [ABSTRACT FROM AUTHOR]

This article presents a polarization independent frequency selective Surface (FSS) with pass band characteristics for the 'S' (1.45–4.63 GHz.) and the 'X' (6.33–12.15 GHz) band. The proposed FSS has a miniaturized unit cell structure with optimized dimensions of 13 ×13×1.605 mm3 that is imprinted on a commercially available FR4 substrate. Four stubs each of length 0.115 λ interleaved at the centre of each inner loop to achieve the required pass band performance. Since it is a symmetric structure, it gives a polarization independent performance for the pass band response (for S and X bands) with both TE and TM modes of operation. The AR bandwidth (< 3 dB) for the 'S' and 'X' bands is 3.2 GHz and 5.82 GHz, respectively. The prototype of the proposed FSS is fabricated and tested using Agilent's E 5063A a two port vector network analyser and two horn antennas with a calibrated gain of 12 dBi each (operating from 20 KHz to 20 GHz). The measured transmission parameters of the FSS that match well with the simulated ones allow its practical applicability for filtering out unwanted signals for the communication satellites, surface ship radars and metrological satellites used in the 'S' and 'X' wireless communication bands respectively. It finds practical applicability in filtering out unwanted signals for the communication satellites, surface ship radars and metrological satellites used in the 'S' and 'X' wireless communication bands respectively. [ABSTRACT FROM AUTHOR]

Recent developments in medium-voltage (MV) silicon and silicon carbide (SiC) power semiconductor devices are challenging state-of-the-art converter and auxiliary power supply (APS) designs. The APS is an important converter component, which energizes the gate-drive units and, therefore, has an influence on the overall reliability and efficiency of the converter system. There has, however, been comparably little research on how the APS of high-power converter submodules can be realized, in particular, for high-voltage applications. New, or improved, solutions may build on state-of-the-art topologies in the near future, but utilize MV SiC technology in the APS circuit itself to enable improved efficiency, reliability, simplicity, and compactness. Externally-fed APS concepts could provide several further advantages. Their various benefits on converter and system level may enable them to be a competitive solution for future APS concepts. Especially, light-based power supply systems are considered most useful since they offer extreme voltage isolation capability and immunity to electromagnetic interference. This article presents a review of the wide range of solutions for APSs, possible implementation options, and the most important design considerations. The different solutions are evaluated in a qualitative fashion, providing an overview of available APS concepts with regard to the requirements for high-power converter applications. [ABSTRACT FROM AUTHOR]

Power Line Communication (PLC) technologies are being used in many applications and offer the advantage of utilizing existing power cables for both power and data transmission, thus minimizing cost and complexity. Nevertheless, PLC technology requires further investigation to solve possible co-existence issues. Indeed, recent studies confirmed that alternative modulation schemes such as Random Pulse Width Modulation (RPWM), applied to switching-mode power converters to minimize conducted emissions, detrimentally interfere with the PLC system. This paper presents an experimental test campaign aimed at investigating the effects of RPWM on the G3-PLC system, with the final goal of understanding the conditions under which RPWM schemes can be considered as an effective alternative to conventional Pulse Width Modulation (PWM) in applications involving PLC systems. In details, the effects of different RPWM parameters such as switching frequency, modulation index, and Random Number Update Rate (RNUR) on the G3-PLC is investigated. In addition, different RPWM schemes such as Random Frequency Modulation (RFM) and Random Pulse Position Modulation (RPPM) are compared in terms of performance so as to highlight which RPWM is best suited to assure coexistence with PLC systems. The impact of RPWM on the communication channel is evaluated in terms of Frame Error Rate (FER), Channel Capacity, and Channel Capacity Loss metrics. Experimental results confirmed that randomly modulated converters with switching frequencies near the G3-PLC bandwidth cause more significant disturbance and possible coexistence issues than the switching frequencies out of this range. Results also show that the modulation index and the RNUR of RPWM have a direct effect on the communication channel. Moreover, a trade-off between Electromagnetic Interference (EMI) reduction and coexistence issues is observed: RFM, which is very effective for EMI reduction, is found to be very disruptive for G3-PLC, compared to alternative random modulation techniques such as RPPM. [ABSTRACT FROM AUTHOR]

High-performance, thin, and lightweight EMI (Electromagnetic interference) materials with outstanding shielding effectiveness were explored over the last years to solve the problems in electronic devices. Magnetic absorbing materials have extensive bandwidth, good impedance matching, and excellent absorption features. In the present study, Sm-Mn Sr-doped M hexaferrites with Sr 1-x Sm x Fe 12-y Mn y O 19 whereas (x= 0.00, 0.025, 0.05, 0.075, y = 0.00, 0.25, 0.5, 0.75) were prepared by the chemical route. XRD, FESEM, HRTEM, FTIR, VSM, and VNA are used to evaluate the properties of the Sm-Mn doped Sr-based M-type hexagonal ferrite. The XRD (X-ray diffraction) results revealed the presence of a hexagonal phase in the prepared samples. Rietveld refinement also confirmed the phase purity for the Sm-Mn doped Sr-based M-type hexagonal ferrites. The FESEM (Field emission scanning electron microscopy) and HRTEM (High-resolution transmission electron microscopy) images revealed the hexagon-type shapes of the particles in the Sm-Mn doped Sr-based M-type hexagonal ferrites. The FTIR (Fourier transform infrared spectroscopy) spectra showed the 446–620 cm-1 lines, confirming the presence of the tetrahedral and octahedral phases of hexagonal ferrites. Dielectric and electromagnetic shielding effectiveness (SE) parameters are evaluated for Sm-Mn doped Sr-based M-type hexagonal ferrite. The electromagnetic parameters, such as complex refractive index, absorption and impedance, are also investigated for the Sm-Mn doped Sr-based hexagonal ferrite powder with x=0.075, y=0.75 having epoxy resin with 20 wt%, 30 wt% and 50 wt% samples, respectively. SE parameters are higher at more extensive filler loading. The green shielding index was found higher for Sm-Mn doped Sr-based hexagonal ferrite powder with x=0.075, y=0.75 having 20 wt% epoxy resin and decreased with filler loading. It is found the epoxy/Sm-Mn doped Sr-based M-type hexagonal ferrites-based composites are excellent absorbers in the Ku band. The investigated absorbers could be the best candidates for next-generation EMI green shielding absorbing devices and applications. [Display omitted] • Sr-Mn doped M hexaferrites were prepared by the chemical route. • XRD, FTIR, SEM, VSM, and VNA were used to evaluate the properties. • FESEM and HRTEM show the hexagon shapes of the hexagonal ferrites. • EMI shielding, dielectric properties, and green shielding index were analyzed. • EMI SET values for the 20, 30, and 50 wt% ferrite composites are 0.7, 0.9, and 2 dB, respectively. [ABSTRACT FROM AUTHOR]

G3-powerline communication (G3-PLC) is a robust communication protocol originally developed for smart metering in low-voltage power distribution networks. Modeling G3-PLC modems is an essential task to investigate electromagnetic compatibility (EMC) issues related to the coexistence of the PLC signal with the high-frequency noise affecting low-voltage networks, mainly due to the presence of power converters and non-linear loads. Since detailed information on the modem internal architecture is usually not available to the end-user, this work investigates the possibility of developing behavioral (black-box) models of G3-PLC modems, whose parameters can be estimated starting from measurements carried out at the modem output ports. To this end, suitable test benches are set up and used for model-parameter extraction as well as for validation purposes. Experiments have proven that an equivalent representation involving non-ideal voltage sources (i.e., in terms of extended Thevenin/Norton equivalent circuits) is no longer feasible for the transmitting modem, since the presence of a closed-loop control system invalidates the linearity assumption. Hence, while the receiving modem is still modeled through an impedance matrix (since it behaves as a linear device), an alternative representation is proposed for the transmitting modem, which resorts to the use of two ideal voltage sources in accordance with the substitution theorem. Experimental results prove that the proposed modeling strategy leads to satisfactory predictions of the currents propagating on the PLC system in the frequency interval of interest. Hence, it could be used in combination with high-frequency models of the other components in the network to investigate EMC and the coexistence of the PLC signal with the high-frequency noise generated by power converters.

Conventional current-source inverters (CSIs) using silicon-based reverse-blocking (RB) switches typically suffer from high conduction loss, low switching frequency, and bulky size. New bidirectional (BD) switches (also called four-quadrant switches) built from wide bandgap semiconductor materials such as gallium nitride and silicon carbide offer both reverse-voltage-blocking capability and low conduction loss that make them appealing candidates for increasing the CSIs efficiency. This article proposes a new modulation scheme for an emerging three-phase CSI topology (H7-CSI) to enable it to operate safely with BD switches to achieve higher efficiency (as much as 3%) compared to the conventional H6-CSI topology or the emerging H7-CSI using RB switch. In addition, this modulation strategy combined with the proposed H7-CSI-BD topology is capable of significantly reducing the conducted common-mode (CM) EMI up to 20 dB⋅μV. Based on this improvement, a promising CM EMI filter network consisting of a CM choke and Y-capacitor has been designed for the H7-CSI-BD topology to meet EMI standards. The required filter component values for the H7-CSI-BD topology are significantly lower than those required in conventional CSIs. Analysis, simulation, and experimental results are provided that confirm the advantages of the proposed BD switch-enabled H7-CSI over conventional H6-CSI and emerging H7-CSI topologies using RB switches. [ABSTRACT FROM AUTHOR]

The demands for carbon fiber reinforced composites (CFRCs) are growing in the aviation industry for fuel consumption savings, despite the increasing risk of electromagnetic interference (EMI). In this work, polyacrylonitrile (PAN) sheets were prepared by electrospinning. Carbon nanofiber (CNF) sheets were obtained by the carbonization of PAN sheets. The laminate structures of the CF reinforced bismaleimide (BMI)-based composites were specially designed by introducing two thin CNF sheets in the upper and bottom plies, according to EMI shielding theory. The results showed that the introduction of CNF sheets led to a substantial increase in the EMI shielding effectiveness (SE) by 35.0% compared with CFRCs free of CNF sheets. The dominant EMI shielding mechanism was reflection. Noticeably, the introduction of CNF sheets did not impact the interlaminar shear strength (ILSS) of CFRCs, indicating that the strategy provided in this work was feasible for fabricating CFRCs with a high EMI shielding performance without sacrificing their mechanical properties. Therefore, the satisfactory EMI shielding and ILSS properties, coupled with a high service temperature, made BMI-based composites a promising candidate in some specific fields, such as high-speed aircrafts and missiles. [ABSTRACT FROM AUTHOR]

The emerging flexible multilayer foils (FMLFs)-based winding design has a great potential to promote the magnetic integration technique in power electronic systems. This article investigates the full integration of a single-phase electromagnetic interference (EMI) choke with well-designed FMLFs. By sharing a UU-type core and configuring the windings reasonably, all the common-mode (CM) inductance and capacitances and differential-mode (DM) inductances and capacitances can be integrated into the same core unit. Moreover, the proper terminal configuration of conductive layers can realize function-decoupling between CM and DM filtering elements, which contributes to simplifying the equivalent CM and DM models, then predigesting the parameters design procedure. Following the modeling and theoretical analysis, prototypes of the proposed and existing EMI chokes have been built for a single-phase 200-kHz SiC-mosfet inverter system. Through experimental measurements, performance comparisons have been presented to demonstrate the validity of this model. [ABSTRACT FROM AUTHOR]

This article investigates the radiated electromagnetic interference (EMI) due to the voltage between input and output cables in a non-isolated power converter. The radiated EMI model of a non-isolated power converter is first developed and quantified based on the circuit topologies, printed circuit board (PCB) parasitics, switching waveforms, and transfer functions. Second, an antenna model is developed for converter cables based on the antenna impedance and the antenna transfer function. Third, a complete radiated EMI model is developed based on the converter's EMI model and the cable's antenna model. Fourth, the radiated EMI is analyzed based on the developed model. Finally, two radiated EMI noise reduction techniques, optimizing PCB layout and adding a cross capacitor, are proposed. The developed radiated EMI model and the proposed radiated EMI reduction techniques are verified with both simulations and experiments. The techniques are also extended to other two non-isolated power converter topologies when the radiated EMI is caused by the voltage between the input and output cables. [ABSTRACT FROM AUTHOR]

This paper proposes a novel control scheme for the buck converter without an inductor current sensor. The architecture of the proposed buck converter is simple and suitable for integration and mass production. It employs an output-voltage-measurement method to determine the switch ON time; therefore, the current sensor is not required. The design specification targets the application with a standard battery power source to generate the low voltages for low-power MCU or ASIC. The load current range aims for several hundred milliamps. The proposed control scheme is analyzed and simulated by SIMPLIS. The control scheme, theoretical analysis, circuit realization, contributions, advantages, and simulation results are presented in this paper. Furthermore, the circuit can be fabricated by a 0.35 μm CMOS process. [ABSTRACT FROM AUTHOR]

Antenna test caps allow the testing of transmit and receive functionality of complete end-to-end radio frequency (RF) space systems in flight configuration outside anechoic environment. The test caps are made of two off-centered cylinders. The upper cylinder contains a probe, corresponding port, as well as a tuning screw. The lower cylinder contains absorbing material, the antenna under test. A full design and its experimental validation are demonstrated for a Martian X-band radio science payload. [ABSTRACT FROM AUTHOR]

The transient current pulse (TCP) caused by the traction network short-circuit fault (TNSF) will produce a high-strength transient electromagnetic field (TEMF). The electromagnetic field will interfere with nearby weak current equipment through the shielded cable. In this paper, a transient circuit model (TCM) for the short-circuit traction network is proposed to calculate the transient current. The short circuit is equivalent to a ring, and the TEMF transient electromagnetic field is calculated based on the magnetic dipole. The current response of the TEMF transient electromagnetic field on the shielded cable is deduced based on the transmission line theory and verified by experiments. The electromagnetic interference (EMI) of a TEMF transient electromagnetic field to the shielded cable terminal load were was studied under various incidence angles, azimuth angles, and polarization angles. The results demonstrate that the greater the incident angle and azimuth angle, the greater the EMI on the terminal load. The horizontal distance between the shielded cable head and the shortcircuit point should be greater than 6 m, and the incident angle should be greater than 45°. This method can provide a theoretical basis for the electromagnetic compatibility research of traction power supply systems and their nearby weak current equipment. [ABSTRACT FROM AUTHOR]

Near-field mapping along the surface of an integrated circuit (IC) could reveal the radiated emission source inside by collecting the radiated electromagnetic field. In this article, the radiated emission source localization is first illustrated in a microstrip line model by analyzing the relationship between the physical position of the line and the hot spots of the electromagnetic field distribution along the line surface. The hot spot in each magnetic field distribution does not necessarily correspond to the physical position of the emission source due to the ground plane below. Furthermore, by analogy with the microstrip line model, the localization analysis is applied to a large-scale IC [field-programmable gate array (FPGA)] in a ball grid array package. For the demonstration, four operation states of the FPGA are designed with four general-purpose input–output (GPIO) pins outputting waveforms of different frequencies. By activating the sources in different operation states, it is found that the activated GPIO pins (as emission sources) can be located well by comprehensively analyzing the emission patterns of different components. The experimental results would be instructive to improve the understanding of IC near-field electromagnetic patterns and reasonable to localize an emission source. [ABSTRACT FROM AUTHOR]

In this letter, the modeling and design of a low-power, compact folded cascode operational amplifier with high immunity to electromagnetic interference (EMI) is presented. The insights derived from the modeling of parameters $V_{gsi}$ , $V_{sbi}$ , and $V_{dsi}$ of the first-stage folded cascode OpAmp with channel length modulation are employed in designing the proposed compact folded cascode OpAmp with 23% reduction in power and 10% reduction in area when compared to the robust folded cascode OpAmp. In addition, a comprehensive comparison of the proposed compact folded cascode OpAmp, classical folded cascode OpAmp, and the robust folded cascode OpAmp is presented when each of these OpAmps are subjected to an EMI of 1.7 Vpp. The postlayout simulation results show that the maximum EMI-induced output offset voltage for the compact folded cascode OpAmp is 6.6 mV over a wide range of frequencies from 1 MHz to 1 GHz by keeping the main specifications intact as that of a robust folded cascode OpAmp. [ABSTRACT FROM AUTHOR]

To identify and improve the electromagnetic compatibility of a global navigation satellite system (GNSS) receiver under a complex electromagnetic environment, the blocking effects of single-frequency and out-of-band dual-frequency electromagnetic radiation (EMR) on a GNSS receiver were experimentally analyzed. This study is the first to investigate second-order intermodulation second-order intermodulation low-frequency blocking (SILB) interference which was newly discovered in our tests. The mechanism of the SILB effect was analyzed, and two key parameters were identified. The SILB interference factor and the relative value of the low-frequency interference level were introduced to establish a model predicting SILB effects. The method of determining the parameters, the modeling process, and the results are discussed in this article on the basis of both theoretical derivations and experimental measurements. A GNSS receiver was used as the equipment under test to verify the model. Notably, the results demonstrated that the threshold for SILB was approximately 30 dB lower than that for out-of-band single-frequency interference. The model proposed in this article accurately evaluated and predicted the SILB interference. [ABSTRACT FROM AUTHOR]

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Motor drive systems with long feeder cables are widely used in mining and energy sectors, such as offshore oil and gas drilling. In recent decades, to prevent issues with electromagnetic interference, power quality standards have been defined for the 2–150 kHz frequency range. In order to comply with these standards, manufacturers need to design filters to avoid exceeding the thresholds set by the standards. An important aspect that needs to be considered is the accurate modeling of currents circulating through common-mode loops. This article addresses this modeling by using a mathematical approach. The power cable’s common-mode model is extracted from the measurement data using the finite-element method via finding the effective permittivity of the PVC materials. The common-mode noise sources, including the grid side voltage through the front-end diode rectifier and the output voltage through the rear-end inverter, are both modeled by extracting the Fourier series calculations. Consequently, noise emissions circulating through different common-mode loops are analytically modeled. Through the proposed modeling strategy, the harmonic spectrum of resonances can be precisely analyzed. The results are validated through simulation and experimental data. [ABSTRACT FROM AUTHOR]

This work proposes a facile fabrication strategy for thermally conductive graphite nanosheets/poly(lactic acid) sheets with ordered GNPs (o-GNPs/PLA) via fused deposition modeling (FDM) 3D printing technology. Further combinations of o-GNPs/PLA with Ti3C2Tx films prepared by vacuum-assisted filtration were carried out by "layer-by-layer stacking-hot pressing" to be the thermally conductive Ti3C2Tx/(o-GNPs/PLA) composites with superior electromagnetic interference shielding effectiveness (EMI SE). When the content of GNPs was 18.60 wt% and 4 layers of Ti3C2Tx (6.98 wt%) films were embedded, the in-plane thermal conductivity coefficient (λ||) and EMI SE (EMI SE||) values of the thermally conductive Ti3C2Tx/(o-GNPs/PLA) composites significantly increased to 3.44 W·m–1·K–1 and 65 dB (3.00 mm), increased by 1223.1% and 2066.7%, respectively, compared with λ|| (0.26 W·m–1·K–1) and EMI SE|| (3 dB) of neat PLA matrix. This work offers a novel and easily route for designing and manufacturing highly thermally conductive polymer composites with superior EMI SE for broader application. [ABSTRACT FROM AUTHOR]

In recent days, Radio Frequency (RF) transmitter plays an important role in the Wireless Sensor Network (WSN). This transmitter uses Pulse Width Modulation (PWM) approach due to its lower power requirement. But, it is the major source of Electromagnetic Interference (EMI) because of its carrier frequency harmonics. In this work, a new RF transmitter is proposed using a chaotic sequence generator and modulation process for the reduction of EMI. The proposed chaotic sequence generator consumes less area and minimizes the hysteresis on the output signal. Furthermore, a Voltage-controlled Oscillator (VCO) with transmission gate tuning logic is proposed to control the oscillating frequency of VCO during RF carrier wave generation. The proposed VCO allows full swing among power rails by consuming less area and power. The proposed RF transmitter is simulated in Xilinx and LTspice working platforms by considering 0.18 μ m CMOS process. The simulation results show that the peak EMI of the proposed RF transmitter is reduced to 39.52 dB μ V, which is 10.56 dB less than that of the standard mode design. Furthermore, the proposed RF transmitter consumes only 0.475 mW power to transmit the RF signal. • Recently, RF transmitter plays an important role in WSNs. This transmitter uses PWM due to its lower power requirement. • he proposed chaotic sequence generator consumes less area and minimizes hysteresis on the output.signal. • A VCO with transmission gate tuning logic is proposed to control oscillating frequency during RF carrier wave generation. [ABSTRACT FROM AUTHOR]

This article gives insights into recent developments in the field of power semiconductor gate drivers that exhibit intelligent features. Such features are active switching transient control and optimization of overshoots, electromagnetic interference, and switching losses. Additionally, these aspects are providing safe operation at fast and extreme switching instances and short-circuit events. Furthermore, integrated sensing capabilities that extract thermal response as well as state-of-health data constitute an intelligent gate driver. During the last decade, researchers transformed gate drivers from simple amplifiers to intelligent control units. Intelligent implies in this context that the driver can gather information and adapt its operation behavior to changing conditions. This includes detecting and clearing fault states, electrical and thermal management, and additionally in situ detection of aging effects. Furthermore, this article identifies challenges and opportunities that arise with intelligent operation of wide-bandgap semiconductors. Future applications of semiconductor devices demand a high level of integration and utilization that can only be achieved by safe operation within but close to their electrical and thermal limits. Intelligent gate drivers provide a unique manipulability that enables high-performance and secure operation through extracting and using information about the switching process and the power module. [ABSTRACT FROM AUTHOR]

This paper proposes a simplified analytical model for electromagnetic interference (EMI) filters used in high-power converters. High-power converters produce radio frequency conducted noise because they use high-frequency switching in the range of a few kHz to tens of kHz. The noise propagates into the power grid, which disturbs the functionality of the radio frequency apparatuses. Well-known standards, such as CISPR, provide the measurement and assessment methodologies for these devices. Moreover, the emission level of the noise is restricted at the source side. Using EMI filters is the most effective approach for dealing with this issue. However, due to the nonlinear nature of the common-mode (CM) cores, the modeling of the cores is a complicated task, which makes the selection and design of the filters less than optimal. In this paper, an analytical modeling of the CM filters is provided to suit the nonlinear frequency-dependent behavior of the CM cores. The simplicity of the proposed model makes it a very suitable choice for inclusion in the design procedures, which results in a more accurate and optimum filter selection among the many available commercial industrial filters. To validate the proposed model, the frequency-dependent model obtained is verified by experimental tests with a commercial CM choke. According to the results, the proposed model accurately describes the actual EMI filter behavior.

This paper investigates the conducted electromagnetic interference (EMI) characteristics of an on-board multiplexing converter that utilizes paralleled silicon carbide (SiC) devices to achieve high efficiency and high-power density for the application in electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs). The multiplexing converter can operate as a three-phase interleaved DC/DC converter with a peak output power of 60 kW or an integrated two-stage non-isolated on-board charger (OBC) with an output power of 6.6 kW. The novelty of this paper is that it reveals that in the DC/DC mode the series resonance between the input negative lead parasitic inductance and the high frequency transmission line effects of the input power inductor will increase the conducted EMI levels, which can be mitigated by optimizing the winding methods of the power inductor or by adding a small capacitor, and reveals that in the non-isolated OBC mode the shielded cable on the battery-side will increase the grid-side EMI in the low frequency ranges, which can be suppressed by integrated installation of EMI filters without affecting the system power density. Firstly, parasitic parameters of the components of the multiplexing converter, such as the power inductors, the SiC MOSFETs and the shielded cables, are extracted and validated with impedance measurements, and the corresponding equivalent circuit models are established. Then, the conducted EMI simulation models of the multiplexing converter in different working modes are established. The influence of different interference sources and different parasitic parameters on the system EMI characteristics are analyzed, and the effective EMI suppression measures are given without affecting the system power density. Finally, the conducted EMI characteristics of the multiplexing converter and the effectiveness of the proposed EMI suppression measures are tested and verified through experiments.

A novel carrier stored trench bipolar transistor (CSTBT) with split gate (SG) and recessed emitter trench (SGRET CSTBT) is proposed. The proposed device features a SG structure with thicker oxide layer under the trench gate and recessed trench emitter, respectively. Compared with the conventional CSTBT with recessed emitter trench (RET CSTBT), the proposed device not only significantly reduces the gate-collector capacitance ( ${C} _{\mathrm{ GC}}$ ) but also alleviates the negative impact of the heavily doped n-type carrier stored layer on the breakdown voltage (BV). Simulation results show that with the similar BV of about 650V, the on-state voltage drop ( ${V} _{\mathrm{ ceon}}$ ) at ${J} _{\mathrm{ ce}}$ =200A/cm2 for the proposed SGRET CSTBT is only 1.11V, which is 0.19V lower than that of the conventional RET CSTBT. Moreover, compared with the conventional RET CSTBT, the ${C} _{\mathrm{ GC}}$ at the ${V} _{\mathrm{ ce}}$ of 25V, total gate charge ( ${Q} _{\mathrm{ G}}$ ) and miller plateau charge ( ${Q} _{\mathrm{ GC}}$ ) for the proposed device are reduced by 84.3%, 38.6% and 51.6%, respectively. As a result, the trade-off relationship between the ${V} _{\mathrm{ ceon}}$ and turn-off loss ( ${E} _{\mathrm{ off}}$ ) as well as trade-off relationship between the turn-on loss ( ${E} _{\mathrm{ on}}$ ) and $\text{d}{V} _{\mathrm{ ak}} / \text{d}{t}$ of the free-wheeling diode (FWD) are significantly improved for the proposed device. At the same ${V} _{\mathrm{ ceon}}$ of 1.16V, the ${E} _{\mathrm{ off}}$ is reduced from 9.2mJ/cm2 of the conventional one to 3.3mJ/cm2 of the proposed device. At the same ${E} _{\mathrm{ on}}$ of 8.3mJ/cm2, the $\text{d}{V} _{\mathrm{ ak}} / \text{d}{t}$ of FWD for the proposed device is reduced by 24.5% compared with that of the conventional RET CSTBT, which significantly suppresses the EMI noise.

Modeling the unintended common- and differential-mode (CM and DM) behavior of multi-converter power electronic-based systems can be a challenge. Chief among the issues is the need for detailed knowledge of the converter hardware to determine model parameters. In this paper, a focus is on the derivation of Thévenin-based models that only require characterization at the converter terminals. Periodic linear time varying system analysis is first used to derive and consider the applicability such models. Subsequently, methods to experimentally characterize Thévenin parameters are established. The modeling approach is then used to establish worst-case predictions of CM/DM behavior of a microgrid which is validated using both time-domain simulation and hardware experiment.

A procedure for the derivation of a black-box model of electromagnetic interference (EMI) filters is proposed and discussed. The modeling approach is assessed by resorting to a real EMI filter. The equivalent circuit of the filter is directly obtained from a rational approximation of the scattering-parameter matrix measured at the filter ports. Therefore, the modeling procedure does not require any information on the internal structure of the filter (e.g., components, electrical/magnetic properties of the involved materials, connections leads, etc.). The circuit model is compatible with SPICE solvers and can be used for the prediction of conducted emissions in both the frequency and time domain. Specifically, the proposed modeling approach allows time-domain simulation and performance analysis of EMI filters in combination with power-electronic equipment (i.e., nonlinear, time-variant circuits). [ABSTRACT FROM AUTHOR]

In this article, a novel circuit is proposed to synthesize absorption common-mode filters (A-CMFs) in only one stage, which can be implemented with different kinds of transmission lines. This proposed one-stage absorption circuit has been derived with analytical equations, and design formulas are found to determine circuit parameters. To validate the proposed circuit and derived formulas, an intuitional structure composed of a meander slotline (MSL), a straight differential pair, and one resistor is proposed. Moreover, a technique named meander asymmetrical coplanar strip (MACPS) has also been developed to reduce the size of MSL-type A-CMF by up to 26%. Finally, the proposed test sample of MACPS-type A-CMF is fabricated in a two-layer printed circuit board (PCB) and measured. The common-mode (CM) noise absorption efficiency of above 80% can be obtained from 2.33 to 2.67 GHz to eliminate CM noises in the Wi-Fi 2.4 GHz band. Besides, the MACPS-type A-CMF provides an excellent differential-mode (DM) signal integrity. The −3 dB bandwidth of DM insertion loss can reach 7.5 GHz, and the measured eye diagram of the proposed work is identical to that of the reference board even the transmitted data rate is up to 16 Gb/s. To our best knowledge, the smallest A-CMF implemented in a two-layer PCB is achieved in this article with the electrical dimension being only 0.0358 λg2. [ABSTRACT FROM AUTHOR]

In some very low noise mixed-signal circuits, designers may use intentional slots in order to create a better isolation between a noisy digital ground and a very quiet analog ground, especially in low-frequency applications ($< $ 1 MHz) when the current spread in the return plane may interfere with the quiet analog ground. Traces on the signal planes, crossing over these slots, are well-known sources for electromagnetic interference (EMI) due to discontinuities on the return current path. This article presents a novel interdigital slot structure used in the reference planes. The interdigital structure increases the coupling and, hence, provides a low impedance path for the return current of the signal line. This, in return, significantly reduces the radiated emission level in the printed circuit boards (PCBs). Furthermore, due to the periodic nature of transmission lines and the slow-wave effect provided by the interdigital structure, the periodically repeating resonance frequencies of the interdigital defect can be tuned by simply changing the geometric parameters such as digit length and the number of digits. It is shown that the electromagnetic radiation from these slots exhibits peak levels at these antiresonance frequencies, which are also the transmission zeros of the circuit. Conversely, radiation levels are minimized at passbands, where a good signal transmission is achieved. Therefore, this relationship would allow designers to tune the slot length to minimize radiation at the frequency of the signal passing through the trace. Four PCBs with three different-size interdigital structures and a traditional slot structure are first simulated and then fabricated. Well-agreed simulation and measurement results show that the EMI is suppressed by as much as 30 dB within the frequency range of 250 MHz–1 GHz. The radiation peaks and dips match with the $S_{21}$ minima (transmission zeros) and maxima, respectively, in measurement results as well. [ABSTRACT FROM AUTHOR]

Static energy meters have shown errors beyond the standards due to conducted electromagnetic interference of pulsed currents. This was observed in several case studies and confirmed by laboratory experiments, which showed errors up to 2675%. The extent of this interference case is unknown, because there is limited information about the waveforms occurring in the real on-site scenarios. This article aims to detect critical waveforms in on-site surveyed data that have similar characteristics as the pulses that resulted in metering errors. The time-domain parameters of the laboratory experiments that show static energy meter interference are compared to the on-site waveform data using an interpolation based on an inverse weighting distance function. Using this approach, the waveform characteristics are compared, and an error is estimated. This approach was satisfactorily validated using data from validation experiments that shows a correct estimation of the actual error according to the permissible limits for energy metering for all validation indices. The performed on-site surveys show the existence of nonlinear waveforms. During the survey of three sites for ten days, 19 531 waveforms were captured, of which 14 487 indicate large nonlinearities and 379 are estimated to produce metering errors up to 925%. [ABSTRACT FROM AUTHOR]

This article presents a strategy for the description of new test waveforms for static electricity meters to be included in international standards. The need of extending the existing standardization frame arises from several recent studies that have reported conducted electromagnetic interference problems of type-approved static electricity meters, resulting in significant errors in the measured electricity consumption. The proposed method is based on discrete wavelet transform and allows for a compact and parsimonious representation of test waveforms, suitable for inclusion in standards. Very few wavelet parameters are concentrating the relevant information to accurately reproduce all the characteristics that the meters need to be tested against. The same parsimonious description cannot be performed with the current practices based on Fourier transform methods since the new test signals need to be highly non-sinusoidal. The discrete wavelet transform is proposed as a more effective tool to sparsely describe the most relevant waveform features. The effect of different discrete wavelet transform decomposition settings on compactness and reconstruction accuracy is studied using suitable metrics. Finally, results from experimental validation with several different waveforms are presented to demonstrate that the error-inducing features can be preserved using only 0.1% of the original signal information. [ABSTRACT FROM AUTHOR]

Passive electromagnetic interference filters (PEFs) are the most common way to solve electromagnetic interference (EMI) problems in power converters. However, PEFs bring additional volume, weight, and cost for power converters, especially common-mode (CM) inductors in PEFs, and it is a tricky issue for the high-power-density converters that must meet the electromagnetic compatibility specification. In order to design compact PEFs for power converters with pulsewidth modulation (PWM), a volume reduction method of CM inductors with chaotic PWM (CPWM) is proposed in this article. First, the mechanism that CPWM reduces the CM inductance by increasing the corner frequency is analyzed. Second, the relationship between the reduction of EMI spectrum magnitude by CPWM and the decrease of the CM inductance is quantitatively calculated. Third, utilization rate of the magnetic core η is defined to reasonably compare the size of the different inductors under traditional PWM and CPWM. Finally, the proposed design method of CM EMI filters is applied into a dc–dc converter and a dc–ac inverter, respectively, to verify its effectiveness and feasibility. In a dc–dc converter with the switching frequency 100 kHz, 275 W, the volume of the CM inductor and the volume of CM EMI filters are reduced by 63.5% and 48.3%, respectively, by using the proposed compact EMI filter. [ABSTRACT FROM AUTHOR]

There are many high-power electrical cables around and within semiconductor foundries. These cables are the source of extremely low-frequency (ELF < 300 Hz) magnetic fields that affect the tools which operate by the function of electronic beams. Miss operation (MO) happens because the ELF magnetic fields induce beam shift during the measurement or process for cutting-edge chips below 40 nm. We present the optimal permutation of power transmission lines to reduce electromagnetic influence in high-technology nano fabs. In this study, the magnetic field was reduced using a mirror array power cable system, and simulation results predicted the best permutations to decrease the electromagnetic interference (EMI) value to below 0.4 mG in a working space without any shielding. Furthermore, this innovative method will lower the cost of high-technology nano fabs, especially for the 28 nm process. The motivation behind this paper is to find the ideal permutation of power transmission lines with a three-phase, four-cable framework to decrease the EMI in high-technology nano fabs. In this study, the electromagnetic interference was diminished using the ideal-permutation methodology without investing or using additional energy, labor, or apparatus. Moreover, this advanced methodology will help increase the effectiveness and reduce the costs of nano fabs. The mathematical and experimental results of the study are presented with analysis. [ABSTRACT FROM AUTHOR]

This letter presents a 3-D electromagnetic interference (EMI) shield fabricated by a commercially available wire bonding technology to reduce EMI between a W-band (94 GHz) integrated-passive-device (IPD) antenna and other function blocks in a package. This EMI shield consists of vertical pillars fabricated by cutting out the wires created from the gold (Au) stud bumps, which are bonded on the nickel/gold (Ni/Au) pads surrounding the IPD antenna that adopts a cavity-backed slot structure. The heights of these wire pillars are made around 500 μm for being higher than that of a normal CMOS chip. The measured isolation (−S21) from the transmitter (TX) IPD antenna to the receiver (RX) IPD antenna, each equipped with this EMI shield, demonstrates the EMI shielding functionality at 93.1–95.5 GHz and maximum shielding effectiveness (SE) of 16.92 dB at 94.2 GHz. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) is a safe and convenient technology for battery charging thanks to the elimination of electrical contact. Despite the great advantages, the electromagnetic interference (EMI) noise generated by a WPT system coulddegrade the performance of nearby electrical circuits. In particular, common-mode (CM) EMI noise generated by the WPT system will conduct along the cable and radiate in high frequencies, thus becoming one of the concerns. In this article, the noise source and current path of the conducted CM EMI noisefrom a Qi-compliant WPT system for mobile applications are analyzed. The transfer function relating the CM EMI noise to the noise source voltage is derived analytically in the frequency domain. The noise source voltage is measured in the time domain and then converted to the frequency domain via fast Fourier transform. The conducted CM EMI spectrum is predicted by multiplying the spectrum of noise source voltage by the transfer function. The prediction matches well with measurement. The analysis and modeling explain the mechanism of the CM EMI noise and provide guidelines to reduce the CM EMI noise. [ABSTRACT FROM AUTHOR]

Near field scanning is one of the most useful methods for electromagnetic interference (EMI) diagnosis. However, large scanning points and long scanning time are the major obstacles when the device under test is complex. To resolve the issue, a novel hybrid method including two steps to quickly predict the near field pattern of an unknown EMI source is proposed. The first step is to reconstruct a full field pattern from a sparse scanning using the joint Schatten p-norm and Lp-norm method, where less sampling points are required on the original scanning plane. The second step is the near–near field transformation based on the plane wave spectrum method. It uses one single field pattern to derive the field distributions on multiplanes around the EMI source by introducing a calibration factor. The source reconstruction method in the second step can also be used to predict far field and coupled power to the victim circuit. Both simulation and experimental examples have validated the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Rapid increase in operating frequency of integrated chips and intricacy of electronic packages outpaces the ability of conventional methods in coping with the growing complexity of electromagnetic interference (EMI) issues. To address it, several machine learning (ML) methods––deep neural network (DNN), convolutional neural network, support vector regression, K-nearest neighbor, and linear regression are constructed to acquire the best ML model to accurately and rapidly predict the maximum 3-m radiated electric field of a wire-bond ball grid array package. The key hyperparameters of different ML models are tuned respectively to attain the least prediction error for each model. Among the optimized ML models, the prediction accuracy of the DNN model is the highest. In this article, a hierarchical attention-based DNN model is proposed and discussed in depth to reduce the number of training datasets, and identify the structural parameters with large contributions to radiation prediction. These structural parameters with contributions can guide the packaging design. The DNN model with attention-weight input requires fewer training datasets than the original DNN model. Furthermore, the experimental measurement for EMI radiation of a test package board is implemented, and the far-field results show the effectiveness and feasibility of the DNN model. [ABSTRACT FROM AUTHOR]

On military platforms, several communication systems are colocated with electronic systems. The resulting electromagnetic environment can degrade communication performance. This is particularly evident in vehicles and other small platforms, where a lot of equipment is installed in a small space. A consequence of high electromagnetic interference (EMI) levels is a reduced communication range for radio systems. The focus of this article is to analyze how a complex interference situation affects frequency-hopping ad hoc networks using synchronized cooperative broadcast (SCB). SCB is a communication technique used by modern tactical wideband radios and a form of cooperative relaying. The interference environment, both background environment and platform interference, is viewed in terms of an increasing equivalent noise figure of the radio receiver. Additionally, there is interference from colocated radio systems yielding internetwork interference. The impact on SCB network performance from these interference sources is analyzed. The results show that SCB is robust toward interference in terms of a maintained high delivery ratio. However, in situations with low network diversity, EMI problems on some platforms can affect the whole network performance. [ABSTRACT FROM AUTHOR]

The drain to gate capacitance (Miller capacitance) of SiC MOSFETs leads to the Miller effect during switching transients. The Miller capacitance in a phase-leg configuration causes the crosstalk, the interaction between the two complementary switches, and the Miller plateau during the switching transient. The Miller effect reduces the switching speed, reduces reliability, and increases electromagnetic interference. In this article, by injecting a mirror cancellation current, the effects of Miller capacitance are canceled. The proposed technique includes a two-stage sensing and injection network to compensate for the nonlinearity of the Miller capacitance. The proposed technique can suppress both positive and negative gate voltage spikes induced by the crosstalk and reduce the switching power loss with the increased switching speed. Because no external control signals are required in the proposed technique, it can work with almost all commercial gate drivers. The detailed design for this proposed technique is presented in this article. The proposed technique was validated with both simulations and experiments. [ABSTRACT FROM AUTHOR]

Forward DC/DC converters are widely used in low and medium power circuits that are widely used in the aerospace and navigation fields. Power converters are usually sources of electromagnetic interference (EMI), which is due to their higher voltage and current transients. The traditional method is to add expensive filters on the primary side or the secondary side, but its disadvantages are high cost and poor adjustability. Based on the principle that the greater the number of derivations of voltage transients, the lower the high frequency electromagnetic interference contained in this voltage, a signal containing small high-frequency noise that is suitable for the hardware circuit as a reference signal is selected, and a closed-loop gate drive method is used in this paper, which attenuate the conducted EMI noise in the input bus of the forward DC/DC converter. The reference signal shapes the output signal to achieve the purpose of suppressing electromagnetic interference through the closed loop circuit. The advantages of this method are making the output highly adjustable, reducing hardware size and weight and lower cost compared with filter method. Compared with the method of controlling current to reduce electromagnetic interference, the proposed method is easier to implement. Firstly, the relationship between the derivative order of voltage transient and electromagnetic interference is introduced. Secondly, the experimental principle of single-ended forward circuit controlled by closed loop is introduced. Simulation and experimental results show that the proposed method can achieve voltage shaping and suppression of voltage overshoot effectively. Compared with the traditional hard-switching control method, the proposed method can make the high-frequency components of the drain-source voltage of the primary-side MOS transistor and the secondary-side output voltage have a greater attenuation.

This paper presents the analysis and design of a miniaturized polarization insensitive metamaterial absorber (MMA) for suppression of the electromagnetic interference (EMI) at microwave frequency range. The proposed MMA consists of a periodic array of double split ring structures printed on an FR4 substrate with a thickness of 0.07 λ0. The simulated results derived from CST indicate that the absorption ratio of the MMA is over 90% with a wide frequency range from 8.3 GHz to 11.3 GHz for a normal incident electromagnetic (EM) wave. To understand the EM wave absorption mechanism, an equivalent circuit model of the MMA unit cell is constructed to investigate the absorbing characteristics, and the electric field and surface current distributions are analyzed at absorption peaks.. Both equivalent circuit model (ECM) and measured results show good agreement. What's more, the measurement data shows that the radiated electric field of the patch antenna at 1 meter is significantly reduced at 10 GHz while loading with the MMA. A maximum suppression of 18 dBμν/m is achieved at 10 GHz. As the proposed absorber possesses good ability on electromagnetic radiation absorption, it could be well applied on printed circuit board (PCB) level EMI suppression.

In the lightning impulse test, the 10 kV fusion voltage transformer intelligent component acquisition port often suffers from functional failure or breakdown. In this paper, experimental measurement and inversion calculation were used to study the electromagnetic disturbance level of smart component acquisition port. During the inversion calculation, the applicability of the dual exponential function model, Heidler function model, and impulse function model as the primary source for describing the lightning impulse device were compared and analyzed. The results show that the double exponential model was used as the calculation source of the primary side lightning waveform, and the inversion calculation results were in good agreement with the actual measurement. In addition, the effects of the primary side lightning voltage peak, wave head, and wave tail parameters on the maximum amplitude of the disturbance waveform calculated by inversion are discussed and analyzed. Based on the analysis results, a sufficient inversion calculation parameter was proposed to estimate the disturbance level of the intelligent component acquisition port. Finally, the measured results were compared and discussed with the IEC 61439 assessment level, and it was suggested that the assessment level of fusion equipment should be modified.

Electromagnetic interference issues are associated with high-speed switching of power converters. EMI modeling is an essential tool to study and control the EMI emission, enabling more efficient solutions. A comprehensive review and comparison of different modeling approaches for conducted emissions are provided in this paper, which can be used as a design guideline for engineers. For a motor drive application, common mode and differential mode conducted emissions are studied, and dominant noise production mechanisms are identified. Moreover, a review of various modeling techniques is presented for the main parasitic components of the system. Finally, time domain and frequency domain analysis approaches are explored along with the equivalent circuits which enable fast prediction of EMI emissions. This paper intends to help the reader develop an organized understanding of conducted emission modeling to assist them with a more efficient and electromagnetically-compatible design.

Modeling the common-mode behavior of power electronic systems can be a challenge. This research aims to simplify the process by developing a modeling approach based on Thévenin common-mode equivalent circuits. The Thévenin common-mode equivalent circuits prove to be both straightforward to construct and reliable in predicting worst-case common-mode behavior. In this paper, a theoretical understanding of the Thévenin-based modeling approach is first provided. Subsequently, methods to characterize the Thévenin parameters are established. The modeling approach is then validated experimentally on a dc micro-grid.

Case reports indicate that magnets in smartphones could be a source of electromagnetic interference (EMI) for active implantable medical devices (AIMD), which could lead to device malfunction, compromising patient safety. Recognizing this challenge, we implemented a high-fidelity 3D magnetic field mapping (spatial resolution 1 mm) setup using a three-axis Hall probe and teslameter, controlled by a robot (COSI Measure). With this setup, we examined the stray magnetic field of an iPhone 13 Pro, iPhone 12, and MagSafe charger to identify sources of magnetic fields for the accurate risk assessment of potential interferences with AIMDs. Our measurements revealed that the stray fields of the annular array of magnets, the wide-angle camera, and the speaker of the smartphones exceeded the 1 mT limit defined by ISO 14117:2019. Our data-driven safety recommendation is that an iPhone 13 Pro should be kept at least 25 mm away from an AIMD to protect it from unwanted EMI interactions. Our study addresses safety concerns due to potential device–device interactions between smartphones and AIMDs and will help to define data-driven safety guidelines. We encourage vendors of electronic consumer products (ECP) to provide information on the magnetic fields of their products and advocate for the inclusion of smartphones in the risk assessment of EMI with AIMDs.

In the PCB process, overcoming common-mode noise radiation is critical. In past years, most studies have focused on a common-mode noise filter (CMNF) that can solve electromagnetic interference in high-speed digital systems by blocking and absorbing common-mode noise radiation. Unfortunately, connecting with any reflective common-mode noise filter (R-CMNF) and reducing the area of an absorptive common-mode noise filter (A-CMNF) are the most troublesome tasks in the PCB process. A novel equivalent circuit is proposed in this research to minimize the complexity of the design and improve accuracy. Detailed analyses of this proposed approach are entirely depicted in this article. The experiment result shows that 9% of fractional bandwidth centered at 2.25 Hz can achieve at least 90% absorption efficiency. With our proposed method, the area of A-CMNF is smaller than in state-of-the-art research.

This article evaluates the electromagnetic interference (EMI) caused by active neutral point clamped (ANPC) phase leg undergoing zero voltage switching (ZVS). ZVS, together with a high fundamental frequency operation is encountered in dual active bridge (DAB) converters. This allows ANPC phase leg to be operated in a different manner than its inverter counterpart. A comprehensive evaluation of four switching schemes for NPC/ANPC-DAB with regard to their EMI performance, voltage overshoot, and losses have been done. Switching state redundancies have been used to reduce the EMI of the ANPC phase leg. To further help in reduction of high frequency EMI and voltage overshoot, a low inductance busbar design has been presented for through-hole discrete devices. Finite element simulation and measurement results show a busbar inductance of 7.7 nH for long commutation loops. Finally, EMI performance (conducted and radiated) together with the busbar design has been experimentally validated for two of the most useful switching schemes. The switching schemes and the busbar design can boost adoption of NPC/ANPC-DAB by ensuring EMI compliance and improved efficiency without affecting the normal DAB operation or using additional hardware. [ABSTRACT FROM AUTHOR]

Power handling capability of a tunable plasma-based multilayer absorber is studied using multiphysics analysis, then validated by experimental data. The proposed two-pole absorber is based on conductor-backed thickness customizable high-order bandpass frequency-selective surfaces (FSSs). Such technique allows simple integration of the tuning elements, while simultaneously providing the option to realize FSSs (including absorbers) with specific/desired thicknesses and transfer responses. Lossy magnetodielectric slabs, used to absorb electromagnetic (EM) energy in the $C$ -band, are added between the metallic layers. The lossy slabs are perforated to host discrete, electrically tunable, ceramic gas-encapsulating chambers (plasma-shells), enabling dynamic control of the absorption spectral band. To study the power handling capability of the proposed multilayered tunable absorber, dielectric and air breakdowns within the device are numerically emulated using EM simulation by quantifying the maximum field enhancement factor (MFEF). Furthermore, a comprehensive thermal analysis using a simulation method that couples EMs and heat transfer is performed for the absorber under high-power continuous microwave excitations. Since the heat generated within the absorber is a primary concern, the steady state as well as transient state temperature distributions have been evaluated for various incident power densities. The performance of the proposed absorber is validated for a prototype having a finite size of $13\times13$ cm2. [ABSTRACT FROM AUTHOR]