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The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.

The nonlinear average model is used in power electronic integration design as a behavioral model, where it is applied to a voltage source inverter based on IGBTs. This model was chosen because it takes into account the nonlinearity of the power semiconductor components and the wiring circuit effects, which can be formalized by the virtual delay concept. In addition, the nonlinear average model cannot distinguish between slow and quick variables and this is an important feature of the model convergence.

The paper studies extensively the construction of the nonlinear average model algorithm theoretically. Detailed explanations of the application of this model to voltage source inverter design are provided. The study demonstrates how this model illustrates the effect of the nonlinearity of the power semiconductor components' characteristics on dynamic electrical quantities. It also predicts the effects due to wiring in the inverter circuit.

More simulations and experimental analysis are still necessary to improve the model's accuracy, by using other static characteristic approaches, and to validate the applicability of the model to different converter topologies.

The paper formulates a simple nonlinear average model algorithm, discussing each step. This model was described by VHDL‐AMS. On the one hand, it will assist theoretical and practical research on different topologies of power electronic converters, particularly in power integration systems design such as the integrated power electronics modules (IPEM). On the other hand, it will give designers a more precise behavioral model with a simpler design process.

The nonlinear average model used in power electronic integration design as behavioral model is a novel approach. This model reduces computational costs significantly, takes physical effects into account and is easy to implement.

The paper aims to present an overview of techniques for the identification in the frequency domain of reduced order models for distributed passive electromagnetic structures.

Most known approaches proposed in different application contexts are described within a unified framework.

A passive reduced order model of an unshielded twisted pair is fully developed with the combination of vector fitting algorithm and the passivity enforcement via Hamiltonian perturbation.

A state‐of‐the‐art picture of the frequency domain identification and passivity enforcement techniques is given, and a test case of actual interest fully analysed.

This paper aims to present the simulation, fabrication and testing of a novel ultra-wide band (UWB) band-pass filters (BPFs) with better transmission and rejection characteristics on a low-loss Taconic substrate and analyze using the coupled theory of resonators for UWB range covering L, S, C and X bands for radars, global positioning system (GPS) and satellite communication applications.

The filter is designed with a bent coupled transmission line on the top copper layer. Defected ground structures (DGSs) like complementary split ring resonators (CSRRs), V-shaped resonators, rectangular slots and quad circle slots (positioned inwards and outwards) are etched in the ground layer of the filter. The circular orientation of V-shaped resonators adds compactness when linearly placed. By arranging the quad circle slots outwards and inwards at the corner and core of the ground plane, respectively, two filters (Filters I and II) are designed, fabricated and measured. These two filters feature a quasi-elliptic response with transmission zeros (TZs) on either side of the bandpass response, making it highly selective and reflection poles (RPs), resulting in a low-loss filter response. The transmission line model and coupled line theory are implemented to analyze the proposed filters.

Two filters by placing the quad circle slots outwards (Filter I) and inwards (Filter II) were designed, fabricated and tested. The fabricated model (Filter I) provides transmission with a maximum insertion loss of 2.65 dB from 1.5 GHz to 9.2 GHz. Four TZs and five RPs are observed in the frequency response. The lower and upper stopband band width (BW) of the measured Filter I are 1.2 GHz and 5.5 GHz of upper stopband BW with rejection level greater than 10 dB, respectively. Filter II (inward quad circle slots) operates from 1.4 GHz to 9.05 GHz with 1.65 dB maximum insertion loss inside the passband with four TZs and four RPs, which, in turn, enhances the filter characteristics in terms of selectivity, flatness and stopband. Moreover, 1 GHz BW of lower and upper stopbands are observed. Thus, the fabricated filters (Filters I and II) are therefore evaluated, and the outcomes show good agreement with the electromagnetic simulation response.

The limitation of this work is the back radiation caused by DGS, which can be eradicated by placing the filter in the cavity and retaining its performance.

The proposed UWB BPFs with novel resonators find their role in the UWB range covering L, S, C and X bands for radars, GPS and satellite communication applications.

To the best of the authors’ knowledge, for the first time, the authors develop a compact UWB BPFs (Filters I and II) with BW greater than 7.5 GHz by combining reformed coupled lines and DGS resonators (CSRRs, V-shaped resonators [modified hairpin resonators], rectangular slots and quad circle slots [inwards and outwards]) for radars, GPS and satellite communication applications.

This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on metamaterial for sensing application has led to the advancement of compact and improved sensors.

In this study, relevant research papers on metamaterial sensors for material characterization published in reputed journals during the period 2007-2018 were reviewed, particularly focusing on shape, size and nature of materials characterized. Each sensor with its design and performance parameters have been summarized and discussed here.

As metamaterial structures are excited by electromagnetic wave interaction, sensing application throughout electromagnetic spectrum is possible. Recent advancement in fabrication techniques and improvement in metamaterial structures have led to the development of compact, label free and reversible sensors with high sensitivity.

The paper provides useful information on the development of metamaterial sensors for material characterization.

The process of identifying unknown hidden objects by taking advantage of electromagnetic effects becomes more and more important. Clearing of mines or finding electrical conductors in concrete should be mentioned here. Magnetisation and eddy currents are the phenomena which are used in general. In this case, the layout and arrangement of the excitation coils and receiving coils influences the effectiveness and accuracy crucially. This design optimization process can be done by simulating the electromagnetic field with a 3D finite element method. Once a satisfying configuration has been found, the question arises, which quantities of the measured (and hence simulated) signals contain the most reliable information? Since the 3D finite element calculations are very time consuming, the inverse problem (detecting the ferrous object from some measured signals) is performed by approximating the corresponding electromagnetic signal by a neural network. Investigations on a ferrous conductive rod will be described in the paper.

There is an unbalanced magnetic pull between the rotor and stator of the cage induction motor when the rotor is not concentric with the stator. These forces depend on the position and motion of the centre point of the rotor. In this paper, the linearity of the forces in proportion to the rotor eccentricity is studied numerically using time‐stepping finite element analysis. The results show that usually the forces are linear in proportion to the rotor eccentricity. However, the closed rotor slots may break the spatial linearity at some operation conditions of the motor.

Reproducible images of human fingertips' induced glow (Kirlian radiation) were captured despite extremely unstable nature of living systems' emission. The matrix of correlations between fingertips' radiation in the electromagnetic field of high frequency and systemic features of human organism has been studied.

Weak natural emission of biological object is enhanced and transformed into visual images by gas discharge processes, which proceed in the electromagnetic field of high frequency. Such secondary radiation was found to be reproducible only when special polyethylene membrane is placed between the glass surface of the camera screen and target fingertip (or other living object). Resulting images of fingertips' discharge coronas provide comprehencible information on the whole living system.

Present research resulted in the discovery of previously unknown phenomenon, which turned out to be specific for living systems. It is demonstrated that Kirlian radiation of fingertips can display almost exact replicas (holograms) of organism's internal organs and tissues. Each part of the body is able to provide holographic information on any problematic element of dynamic system. Holodiffractional nature of discovered phenomenon has been confirmed experimentally.

The discovery of new natural phenomenon represents a major step forward regarding both theoretical disciplines and practical biomedicine. Secondary holodiffractional radiation of body parts provides previously unavailable information on dynamic organization of the whole living system. Bioholographic information is already widely used for diagnostics of body/mind pathology.

The purpose of this paper is to describe the implementation of a direct torque control strategy dedicated to three‐switch three‐phase delta‐shaped inverter (TSTPI) fed induction motor drives as well as the comparison of its performance with those yielded by six‐switch three‐phase inverter (SSTPI) fed induction motor drives under the Takahashi DTC strategy.

Referring to the asymmetrical stator voltage vectors and in order to reach high dynamic with low ripple of the electromagnetic torque response, the design of the vector selection table should include virtual voltage vectors by the subdivision of each sector into two equal sub‐sectors.

It has been shown that the implementation of the proposed DTC strategy in TSTPI‐fed induction motor drives leads to higher transient behaviour and better steady‐state features than those exhibited by the Takahashi DTC strategy implemented in SSTPI‐fed induction motor drives.

The research should be extended to a comparison of the obtained simulation results with experimental measurements.

A 50 per cent reduction of cost and compactness associated with a 50 per cent increase of reliability makes the TSTPI an interesting candidate, especially in large‐scale production applications such as the automotive industry.

The paper proposes an approach to improve the cost‐effectiveness, the compactness and the reliability of TSTPI‐fed induction motor drives, which represents a crucial benefit in electric and hybrid propulsion systems.

This paper aims to derive a simple and effective but still a reasonably accurate model for electromagnetic problems with hysteretic magnetic properties and/or induced currents in heterogeneous regions in 2D, meant particularly for non‐destructive testing (NDT) of steel cables by eddy‐currents.

It is assumed that the diffusion of electromagnetic fields in a heterogeneous cable, which consists of many strands, can be described by the Maxwell equations with periodically oscillating coefficients. A computationally efficient model can then be derived. The idea behind this is to replace the heterogeneous material in the cross‐section by a fictitious homogeneous one, whose behaviour at the macroscopic level is a good approximation of the one of the composite material. Such a homogenized model is obtained by employing the two‐scale convergence.

The model is validated based on experimental electromagnetic data from a steel cable (measured magnetic hysteresis loops) to show that the model is applicable for NDT of cables. The model is useful for studying NDT of cables, both for excitation at low frequency (where changes in magnetic properties are investigated) and at higher frequency (eddy current testing). It is valid for a wide range of amplitudes and frequencies.

From the mathematical point of view the model incorporated a non‐local boundary condition that has to be included in the analysis. From the engineering point of view, by solving an inverse problem based on this model and on measured hysteresis loops at several frequencies, a broader range of defects in the cable can be detected.

The purpose of this paper is to study the microwave behaviour of effective magnetic permeability for two‐component ferrite like metamaterial medium in the direction of a biasing magnetic field. The metamaterial medium is presented as an infinite host dielectric material (air) with periodically embedded ferric cylindrical and spherical inclusions saturated with an external dc magnetic field. The study is based on the effective medium theory developed for polycrystalline metaferrites. The simulations show that the presented metamaterial can exhibit the ultra‐low refractive index (ULI) phenomenon and the phenomenon of negative magnetic permeability for the case of microwave propagation in the direction of bias.

The obtained results are based on the wave long approximation of permeability tensor of the presented metamaterial media obtained earlier by the first author. Using the standard approach, the authors apply the above expressions for the microwave propagation in direction of biasing dc magnetic field considering different polarization of the incident microwave.

The considered artificial material media can become either material with a ULI or with negative values in the GHz frequencies.

The paper is concerned with part of the theory of a new generation of artificial ferrites.