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Irregular-shaped wiring structures are usually encountered in practical applications. In this work, a wiring structure encompassing a loop is modeled geometrically by resorting to a 3D cylindrical helix. To predict the disturbances induced by an incident electromagnetic field at the terminals of such a nonuniform structure, a simplified numerical solution based on transmission-line (TL) theory is developed. To this end, the structure is discretized in segments and the Agrawal TL model is formulated by accounting for the actual orientation of each wire segment with respect to the incident electric field vector. Full-wave simulations of the current induced in the terminations of the wiring structure under analysis are used to validate the accuracy of the proposed numerical TL-based method as well as its computational effectiveness.

The measurement of harmonics is essential in modern power systems in order to perform distortion level assessment, disturbances source detection and mitigation, etc. In this context, the role of Instrument Transformers (ITs) is crucial, as they are key elements in every power systems measuring instrument. However, inductive ITs, which are still the most widely used, suffer from both a filtering behavior due to their dynamics and from nonlinear effects due to their iron core. The target of this paper is to deeply analyze the performance of two digital signal processing techniques, recently proposed in literature, aimed at mitigating their nonlinear behavior: they are SINDICOMP and the compensation of harmonic distortion through polynomial modeling in the frequency domain. Their performance in improving the measurement of voltage harmonics are analyzed through numerical simulations, by adopting waveforms that can be typically encountered in power systems during normal operating conditions., "This project 19NRM05 IT4PQ has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme". Funder name: European Metrology Programme for Innovation and Research (EMPIR) Funder ID: 10.13039/100014132

This paper describes the project of an optical measurement system, an evolution of the system currently installed on the lathe for turbine palettes refinement in Ansaldo Energie, developed by the Politecnico di Milano. This article analyzes the most significant causes of errors found in designing an optical measurement system, proposing improvements that can optimize the system, both in terms of performance and reliability. The idea behind this work is to develop a system that can measure with an accuracy of $10\ \mu\mathrm{m}$ the difference of length of palettes of a turbine stadium in real time, while the turbine is turning on a refinement lathe.

To ensure frequency stability of low inertia power systems, VSC needs to provide frequency response (FR) service. Limited by predicting grid inertia/damping and disturbances that are difficult to measure, the FR performance is greatly restricted. Besides, excessive response under certain conditions results in several consequences, including 1) energy waste, and 2) the VSC power frequently and excessively deviating from steady-state points, thereby reducing the component’s life, lowering system safety/reliability, and increasing the risk of VSC overcurrent faults. To solve these issues, this paper proposes the frequency trajectory planning (FTP) based FR strategy, with the fundamental idea to actively plan the frequency trajectory with necessary safety margin in accordance with the grid code. Specifically, if the system frequency locates within the range of planned one (suggesting frequency indexes satisfying the requirement), VSC remains at the steady-state point to avoid excessive FR service; otherwise, the FR service is required, and the FTP control is enabled to closely track the planned trajectory. By fulfilling the tracking purpose, the requirement on system frequency indexes is met, frequency stability is guaranteed, and the over-response is avoided. Namely, the planned trajectory can characterize whether the system requires FR service and whether the provided FR service is sufficient or excessive. Additionally, the method needs no measurement of inertia/damping and disturbances of the system, and can be directly integrated into the commonly used VSC control systems. Finally, experiments prove the effectiveness and advancement of the FTP strategy.

The use of power electronic converters to interface renewable sources and intelligent loads to electricity distribution systems is increasing at a rapid rate as they bring flexibility and control to the system. However, they also bring an increased level of conducted emissions (CE) to the system due to their switching behaviour - usually at a few tens of kilohertz. The increased emissions are seen particularly in the low-frequency range (2–150 kHz) and it may possibly impair the operation of information and communication technology (ICT) equipment connected to the same system. It is therefore essential to assure accurate measurement of low frequency emissions from a particular piece of equipment, to ensure it meets standards for electromagnetic compatibility (EMC). According to EMC standards, CE are usually measured by using a Line Impedance Stabilization Network (LISN). However, the standard LISN bandwidth does not fully cover this low-frequency range (2–150 kHz), resulting in inaccurate measurement and poor repeatability. This paper examines this issue, by investigating the limitations in using the CISPR 16-1-2 LISN topology for CE measurement at low frequency in a grid-tied inverter system, and by proposing a possible solution, which requires adding extra components to the LISN circuit.

Modern distribution networks are characterized by higher distortion and wider variability of voltages and currents. Accurate synchrophasor, frequency and ROCOF measurements thus ask for new techniques trying to reduce latency while limiting the impact of spurious components. Taylor-Fourier Multifrequency approach is a good candidate for Phasor Measurement Units intended for distribution system applications. In this paper, an improved version of this method is proposed, relying on the potentialities carried by window functions in both support identification and estimation. Its potentialities are assessed through non-standard test conditions, confirming the enhanced accuracy.

Behavioral modeling and identification of nonlinear time invariant systems in the frequency domain represents an extremely interesting and up to date topic in widespread application fields. The frequency-domain Volterra-Wiener (or polynomial) approach is one of the most widely employed, since it can be derived as the straightforward extension of the usual frequency response function to the nonlinear case. Its main drawback is that its complexity rapidly grows with the number of input harmonic components and nonlinearity order. The purpose of this work is presenting a method to reduce the number of coefficients defining the Volterra models by exploiting a priori knowledge about the input signal spectral content. Similarly to the spectral linearization approximation which is commonly used in radiofrequency and microwave applications, input components are classified into "large" and "small" according to their expected amplitudes. The output spectrum is computed by considering all the possible interactions between large components according to the Volterra theory. On the contrary, interactions between small components are neglected. The proposed modeling approach has been tested in numerical simulations on a Hammerstein system; results clearly show the advantages with respect to a conventional polynomial model.

Effective design of active filters for specific applications poses several challenges to EMC engineers. If on the one hand, the theoretical considerations available in the literature are complete and exhaustive, on the other hand, when moving to actual filter implementation, some practical considerations on the final application are mandatory. The first aspect to be carefully accounted for regards the actual source and load impedances of the system where the filter is installed. Concerning this, it will be proven that not only the impedance magnitude but also the phase plays a significant role, since disregarding it may lead to undesired oscillations, noise amplification or saturation of the electronics. Also, the non ideal behavior of the involved circuitry has to be considered when predicting the insertion loss of an active EMI filter. An enhanced circuit model of the filter is proposed and its effectiveness for the prediction of the filter insertion loss is proven by measurements on a common mode active filter in the frequency interval from 10 kHz up to 108 MHz.

The integration of battery energy storage systems in electrical grids is one of the most interesting challenges of the recent years. In this regard, one potential solution is based on a modular multilevel converter (MMC) with batteries directly embedded at each submodule level. This solution allows to reach medium voltage level using low voltage devices avoiding the necessity of complex battery management system to balance the high voltage battery modules. Several studies have been performed on MMC topologies to integrate storages. Nevertheless, there are not dedicated studies to analyse the effect of the number of levels on efficiency and cost of the final solution. This paper focuses on the efficiency evaluation and on the cost analysis of the MMC combined with energy storage systems. After evaluating the total power losses of the converter, the efficiency for different number of submodules is analysed. In addition, cost comparison between different solutions, taking into account several factors such as component price, converter power losses cost and operational & maintenance cost, is discussed.

Recently, multiphase machines have gained worldwide attention from the research community and industry for their applications in the electric ship propulsion, electric transports, more-electric aircrafts and for those particular loads that require continuous operation of the machine after one or more phases become open-circuited. A fault can be due to the loss of one of the leg transistors in the voltage source inverter, or be internal to the machine, affecting one of the phase windings. Multiphase machines can continue to operate even in the case where more than one phase is open-circuited, while for a three-phase machine, post-fault operation is possible only if one phase is opened and the star point of the machine is connected to the dc mid-point of the inverter.In this papers the modeling and control of a five-phase induction machine with the field oriented control technique are presented; then, an algorithm for the post fault operation when one stator phase is open-circuited has been proposed and the results of the simulations, carried out with different load torques and reference speeds, have been reported and discussed.

A machine learning-based framework is proposed to evaluate the effect of design parameters, affected by both aleatory and epistemic uncertainty, on the performance of antennas. In particular, possibility theory is leveraged to define aleatory and epistemic uncertainty in a common framework. Then, a method combining Bayesian optimization and Polynomial Chaos expansion is applied to accurately and efficiently propagate both uncertainties throughout the system under study. A suitable application example validates the proposed method.

The modular multilevel converter (MMC) for electric vehicle applications has been studied in recent years, for its advantages such as high modularity, fault tolerant ability and capability of multi-function (motor drive, cell equalizer and on-board charger) integration. However, during the operation of MMC, specific ac harmonics will be introduced in battery cell currents, reducing battery lifetime. A multiple common-mode voltages injection control method, increasing the frequency of the 2nd order current harmonic and allowing the filtering through smaller filters, is proposed in this paper, to mitigate the negative influence of current harmonics on battery lifetime. To eliminate the effect of injected common-mode components on the ac side, a hybrid MMC topology is also proposed. Simulation results verify the validity of the proposed method and topology.

In this work, a transmission-line model of a typical Power over Ethernet configuration, where data and power share the same transmission medium, is investigated by resorting to modal decomposition. It is shown that in the ideal case in which all circuit components behave ideally, data and power propagate through different paths without interference. The obtained modal circuits are then used as starting point to investigate the detrimental effects on signal transmission introduced by possible imbalance (i.e., asymmetry with respect to ground) affecting the involved circuit components.

Property of fluid and material compatibility limit the level sensor’s fabrication, dynamic range and accuracy. Piezoresistive pressure sensing elements with media compatible diaphragm are limited in low pressure dynamic. In contrast, capacitive pressure sensing elements provide better solution in terms of dynamic range. In this paper, liquid level measurement is realized through a capacitive differential pressure sensor. A custom digital synchronous detection is implemented in order to optimize the measurement performances, gaining a sensitivity of 40 ppm/mm. Different operating frequencies have been defined and a DFT based feedback loop is proposed in addition to eliminate the impact of interferences at predefined frequency. The sensor characterization indicates linear response. The maximum error is limited to 0.3 mm in range of 0- 200 mm as level displacement.

A novel machine learning-based framework is presented to evaluate the effect of design parameters, affected by epistemic uncertainty, on the Signal Integrity (SI) and Electromagnetic Compatibility (EMC) performance of electronic products. In particular, possibility theory is leveraged to characterize the epistemic variations, and is combined with Bayesian optimization to accurately and efficiently perform uncertainty quantification (UQ). A suitable application example validates the proposed method.

The availability of grid storage for photovoltaic residential installation can play an important role in both the scenarios of managing excess energy and of stabilizing transient frequency. Starting from these considerations, the estimation of battery lifetime is an essential issue in energy system planning, operation and maintenance. Major degradation mechanisms related to batteries determine an overall item aging: their effects determine a reduction of the battery capacity and an increase of the internal resistance of the cells. The degradation can be considered unacceptable when the capacity of the battery is below the 80% of the nominal one and when its State of Health (SOH) is considered 0%. This work presents an algorithm to manage in a satisfying economical way the storage battery system for residential photovoltaic plants. The novelty of this study is the addition of degradation mechanisms that unavoidably affects the battery, in an economical optimization, so that the consumer can exploit the best theoretical trade-off between minimum cash flow and maximization of the battery lifetime. In the proposed algorithm, degradation mechanisms are considered taking into account two aging typologies: cycle aging and calendar aging.

In modern metrology it is increasingly common to find the importance of thickness measurements in the production processes of compact materials (metals, plastics, paper, rubber, etc.). A quick and timely measurement is indispensable in those automated industrial processes capable of modifying the production parameters in real time in order to have the characteristics exactly suitable for the needs. The idea of the development of this kind of instrumentation it is starting from this. The requirements that the system will have to respect, including the importance of having a meter that must not be in contact with the plastic film and that can only be positioned on one side of it. These restrictions require the choice of a measurement methodology to be sought mainly in the optical field.

In this paper, a novel approach to complex impedance measurement is proposed, using an Impedance Analyzer (IA) connected to the system under investigation through a transformer, which allows direct measurement of the magnitude and phase of the common mode (CM) and differential mode (DM) impedance of a Switched-Mode Power Supply (SMPS) during working conditions. The theoretical analysis of the measurement circuit both for CM and DM impedances is provided as the first step. Then, a fine calibration process is explained and validated with passive components. Eventually, the proposed method is exploited for experimental evaluation of the CM and DM noise impedances of an automotive SMPS in a test set-up for conducted emission verification.

Voltage transformers are vital components for the operation of power systems. Because of the increasing diffusion of power electronics, nonlinear devices in distribution grids, their role is becoming even more important, since they represent the input stage in power quality monitoring instruments. Nevertheless, their metrological performances are still expressed in terms of accuracy class, namely rating maximum ratio and phase errors at fundamental and harmonic frequencies. The aim of this work is providing a contribution that allows migrating from the concept of maximum error to that of uncertainty. Calibration of an inductive voltage transformer has been considered as a case study and simulated through detailed modeling; this allows neglecting the impact of noise and that of the reference transducer. The statistical features of the measurement error are evaluated, and a method to quantify and express uncertainty is proposed.

HVDC is a recognized economical and technical advantageous solution for long distance transmission, asynchronous interconnections and long submarine cables crossing. The number of projects already in operation or under consideration has increased in the last years, reflecting the global interest on this technology. The new converter designs have permitted HVDC to be used in a wide system application options, such as underground interconnections and offshore renewable energy generation. HVDC technology presents an economical solution for power transmission, with fewer losses when compared to equivalent high-voltage AC systems. The converters nonlinearity operation produces some effects in the transformers, such as, additional losses, vibration and noise level increase. In many cases, the design solution to deal with those effects is to increase margins, what may affect not only the transformer manufacturing cost, but also its operating life. This article discusses the most relevant effects produced by the line-commutated converters (LCC) technology listed on IEC/IEEE 60076-57-129 technical standard, analyzing the consequences into the converter transformer operation and design considerations.

Synchronized phasor and frequency measurements are key tools for the monitoring and management of modern power systems. In a dynamic scenario, it is fundamental to define algorithms that allow accurately measuring time-varying signals, with short latencies and high reporting rates. A dynamic phasor model can help the design of these algorithms and, in particular, of those based on Kalman filtering approach. In this paper, an Extended Kalman filter formulation that considers the Taylor expansions of amplitudes and phase angles in three-phase signals is introduced. The proposed dynamic model takes into account the inherent relationship among the phases and includes harmonics in a effective way. The performance of the method permitting both synchrophasor and frequency measurements are assessed by simulations, considering also the combined effect of dynamics and disturbances. The algorithm shows tracking capabilities and the flexibility which is mandatory to deal with different conditions.

Studying the impact of nonlinear devices on harmonic pollution represents a very important task, especially in modern distribution grids. In this case, harmonics are produced by the large amount of power electronic devices, which is going to further increase because of the growing penetration of diffuse generation and the expected diffusion of plug-in electrical vehicles. Suitable nonlinear frequency-domain models are required for the purpose, and the frequency transfer matrixes approach is typically employed. A possible alternative approach comes out from a suitable simplification of the Volterra series. The derived models are defined by a reduced set of coefficients and they allow reaching good accuracy for a wide range of input values. The performance of this approach is evaluated through numerical simulations by predicting the input current of a bridge rectifier operating in continuous conduction mode.

Phasor measurement units represent the most advanced measurement devices in ac power systems. Their most important feature is permitting to estimate synchrophasor, frequency and rate of change of frequency of voltages and currents in a shared, synchronized timescale. Most of the estimation algorithms have been designed to operate with a unique signal; however, ac power systems are inherently three-phase and weakly unbalanced during regular operation. Therefore, these three-phase signals benefit from peculiar properties than can be leveraged by specifically suited measurement algorithms. For this reason, space vector based techniques have been proposed. Usually, the reference frame is supposed to be stationary or rotating at the rated angular frequency. This work proposes to exploit measurements performed in a previous reporting instant in order to generate the instantaneous angular position of the reference frame, so that it tracks the phase evolution of the positive sequence synchrophasor. A P class implementation is reported, and the results highlight excellent performance. Accuracy is remarkable even under conditions going well beyond those required by compliance tests.

The application of modular multilevel converter (MMC) in electric vehicle (EV) system is being studied in recent years as one of the emerging research topics, for its various advantages such as high modularity, fault tolerant capability, high quality output and the ability to integrate function of motor drive, on-board charger and cell equalizer. However, specific ac current harmonics introduced by operation of MMC will speed up battery degradation and are harmful to battery lifetime. In past researches on MMC in EV, there is no related study solving this problem. In this paper, an improved control method of MMC based on second order circulating current injection is proposed, mitigating the negative influence of current harmonics on battery lifetime, without increasing hardware cost. Simulation results in MATLAB/Simulink verify the effectiveness of proposed method.

Steel fiber reinforced concrete (SFRC) is a widely used construction material in the modern civil and building engineering. When steel fibers are incorporated into a concrete matrix, significant improvement in the mechanical behavior with respect to the parent plain concrete can be obtained. Several researches have shown that the mechanical performance of SRFC strongly depends not only on the fiber content, but also on the orientation in the concrete mixture with respect to the applied stress. Therefore, measuring these parameters, especially on-site, is a goal of the utmost importance. As a matter of fact, non-destructive measurements are preferable and the cost of these tests should be as cheap as possible. In this paper, a cost-efficient, hand-held measurement device is presented. It is based on a magnetic probe, which is very sensitive to ferromagnetic material such as steel fiber. First, the working principle of the measurement method is discussed. Then, the experiment validation of this device as well as the comparison with a previously developed reference device are reported.

This paper investigates the efficiency of a perturbative approach for the statistical assessment of differential transmission lines affected by random parameters. Within the polynomial chaos framework, the novel technique reformulates the so-called stochastic Galerkin method in a decoupled and iterative fashion. Instead of solving the classical, augmented and fully coupled transmission line equations, the new approach iteratively solves multiple uncoupled line equations with nominal per-unit-length parameters and suitable equivalent distributed sources accounting for their variability. The methodology is applied to a system of up to four PCB differential pairs. A computational advantage is observed against the classical stochastic Galerkin method for large problems in terms of number of random parameters and/or conductors.

This paper presents a novel approach for the statistical analysis of differential interconnects with random parameters. The proposed method employs a perturbation technique to reformulate the augmented multiconductor transmission line (MTL) equations generated by the polynomial chaos based stochastic Galerkin method. The augmented MTL-like equations are recast as the equation for a deterministic MTL with average per-unit-length parameters and additional equivalent distributed sources that account for their variability. The process leads to multiple MTL problems of the same size as the original one, which are solved iteratively in the frequency domain. Moreover, for each iteration, the solution of each MTL problem is independent. The feasibility of the proposed approach is illustrated through the statistical analysis of a canonical PCB differential line with random geometrical parameters. Computational advantages with respect to the classical stochastic Galerkin and Monte Carlo methods are discussed along with the effect of the amount of variability on the performance.

The widespread diffusion of nonlinear power electronics devices in power systems has radically changed their operating scenario. Voltage and currents can be significantly distorted, and conventional linear models of power system components may be not accurate enough. Simplified Volterra models with quasi-sinusoidal excitation have been recently proposed, and they are particularly suitable to represent the behavior of power systems devices. In this paper, the simplified Volterra approach is applied to the frequency-domain modeling of a typical highly-nonlinear load: a full-bridge rectifier feeding an ohmic-capacitive load. Model accuracy has been evaluated by means of numerical simulations, and its performance has been compared with that achieved by a conventional Volterra model. Results highlight the excellent accuracy of the proposed model in spite of the relatively small set of coefficients to be identified. This feature is extremely important when models have to be employed in frequency-domain simulations of large networks.

Pulsed current injection (PCI) allows testing the immunity of electric/electronics devices against fast and intense transient electromagnetic disturbances. This technique resorts to inductive couplers to directly inject noise currents into the harness entering the device under test (DUT). Although the characteristics of the stress waveform to be induced at the DUT input are assigned by the Standards, and set by calibration, the noise actually entering the DUT input ports may exhibit significant differences due to the frequency response of the injection device itself as well as specific setup arrangements. To investigate these influence factors, possibly compromising test significance, in this work a PCI test setup involving a wire-pair is setup and modeled in the SPICE environment. Measurements and simulations are exploited to put in evidence the effects that the presence of other wires (and their terminations) in the bundle play on the voltage waveform induced at the terminations of a specific wire. The results here presents are significant also in view of extending the analysis to more complex wiring configurations (currently ongoing), and in order to correlate the PCI technique with radiative immunity procedures foreseen by the Standards.

Up to few years ago, one of the main problems in the optimal design of a battery energy storage system (BESS) was the availability of both the generation (e.g. renewable sources) and load power profiles of the considered plant. This paradigm has limited the potential of BESSs to drive down overall energy costs and reduce carbon emissions. Nowadays, the exponential growth of data available on the industrial plants has opened the way to new possibilities and opportunities. In addition, BESSs are a viable opportunity to start transforming existing plants with an incremental hybridization of the plant topology. In light of the above, this work develops a commissioning tool that, starting from the data collected on the field, provides the final users the optimal dimensioning of any BESS - according to the taraet performances required bv the specific application.

Nowadays, electric vehicles (EVs) are of great interest over the world. In the past, the diffusion of EVs was impeded because of the limits of energy storage units, which reflect in vehicle range limited extension. In recent years, a significant progress was made in terms of power and energy density thanks to the lithium based batteries that can guarantee vehicle ranges higher than 100 km. Another further step can be done by coupling more than one storage technology and leading to an increased efficiency and extension of the vehicle range. In this paper, the effectiveness of adding another storage unit to a lithium ion battery is investigated for different EVs and driving cycles. Furthermore, a methodology procedure, based on the knowledge of the test driving cycle, and parameters of the EV, is proposed to find the optimal size of the auxiliary storage, that maximizes the EV range.

Phasor measurement units (PMUs) are the key measurement devices of modern power networks monitoring systems. The high accuracy and fast reporting rates required for PMU implementations ask for improvements in both hardware and software solutions. Depending on the characteristics of the monitored voltages and currents, the accuracy of PMU algorithms may represent the main contribution to the overall measurement performance. For this reason, research is ongoing in the field of signal processing techniques for phasor and frequency estimation. In this context, Interpolated Discrete Fourier Transform (IpDFT) is one of the most interesting techniques, mainly because it allows accurate measurements under off-nominal frequency conditions while preserving simplicity and computational efficiency. In this paper, the applicability of IpDFT to three-phase signals that are typical of power networks is discussed. Then, it is proposed to combine the advantages of IpDFT with those of the Space Vector approach for positive sequence synchrophasor and frequency measurements.

The modern Distribution Systems (DS) require for accurate and fast Power Flow (PF) algorithms as a basis for other DS applications. Almost all decisions are taken based on accurate PF results and, possibly, they have to be taken in real time. In this paper, a new PF algorithm based on a linear programming approach is proposed. The graph theory is used for modeling the distribution network with some topological matrices. The proposed matrices are then utilized to develop a linear optimization model in rectangular form for PF in DS. Moreover, a linear load model is used for calculating the current injections in each system bus. This leads the PF equations to be linear with acceptable accuracy. In the paper the proposed PF algorithm is implemented on IEEE 18-bus and 33-bus test systems. The results show the accuracy and the performance of the proposed PF model compared to existing models. Since the optimization model is linear, the solution is global optimum. It facilitates the application of the accurate PF results in real-time optimization of DS.

This work investigates the mechanism of generation of undesired common-mode (CM) currents in differential-line interconnects with slight non-uniformity owing to imperfect production process. To this end, three different non-ideal configurations are considered, obtained by perturbation of an ideally-uniform differential interconnect composed of two microstrips. By resorting to modal analysis, the governing transmission line equations are written as a perturbation of those of the ideal structure. This allows circuit interpretation of the mode conversion phenomenon in the analogy with crosstalk. The role played by each geometrical parameter (varying along the line) on the frequency response of the common- and differential-mode quantities induced at the line terminals is shown and discussed.

Possibility theory is briefly presented and proposed for the evaluation of epistemic uncertainty in electromagnetic-compatibility models. In particular, fuzzy sets are exploited to describe some unknown/uncontrolled model parameters which cannot be rigorously treated through probability theory, since their statistical distribution is unknown. A hybrid approach is used to combine such possibilistic parameters with classical probabilistic parameters described by random variables, so to obtain a general, exhaustive description of uncertainty in model outputs. As an illustrative example, the proposed approach is applied to the estimation of differential mode currents induced in the terminations of a twisted wire pair with an unknown number of twists, illuminated by a random plane-wave field. The obtained results are compared versus conventional Monte Carlo simulations.

In this work, the mechanism of differential-to-common-mode (CM) conversion arising in differential interconnects due to bend discontinuities is investigated. A circuit interpretation of the phenomenon is provided in terms of lumped sources of interference included into the equivalent CM circuit. The obtained circuit model, assessed through full-wave simulation, allows inferring analogies and differences with respect to other sources of CM generation such as asymmetries and non-uniformities of the line cross-section, possibly occurring due to the manufacturing process. It is shown that the bent section can be interpreted as a local perturbation of an ideally uniform and symmetric microstrip cross-section and, as such, included into a more general simulation framework based on a perturbative approach aimed at the CM prediction in differential interconnects.

In a previous work, the possibility to eavesdrop digital signals transmitted along differential interconnects was explored by resorting to sensing loop(s), operated as hardware Trojans placed in close proximity of the data lines. To maximize coupling, ideal (i.e., symmetric) positioning of the receiving loop(s) with respect to the differential interconnect was considered. However, since in practice misalignment between the two circuits may occur, this work investigates robustness of the eavesdropping algorithms to possible geometrical deviations from the ideal (symmetric) configuration. Here, the objective is to assess accuracy of the proposed methods in reconstructing the original waveforms even in case of nonideal positioning of the receiving loop(s).

A novel integrated optical electric field sensor employing the asymmetric Mach-Zehnder interferometer especial for electromagnetic pulse measurement is analyzed and optimized design utilizing the multi-physics coupling model. Tapered antenna for the sensor is analyzed in CST software. The multi-physics equation and model are analyzed. Antenna structure and size are optimized using CST. Meanwhile the asymmetric waveguides including 3 dB coupler are optimized based on the operating point adjustment range over 90°. In the simulation model, the measurement range of the sensor can reach to 90 kV/m. R2 of the fitting curve of the measurement range is 0.986. Simulation results of the time domain response of the antenna in CST and waveguide in COMSOL are combined when analyzing the frequency response. The results shows that the frequency response ranges from 1 GHz to 10 GHz with less than 3 dB deviation.

This paper investigates the performance of an automotive RKE (Remote Keyless Entry) system under the influence of RF interference, injected by the Bulk Current Injection (BCI) test technique. Measurements indicate a severe degradation of performance in the 15 MHz–30 MHz frequency band where RF current injection level is set at 106 dBμA. Injection at these frequencies leads to failure in correct operation of the RKE system. The analysis clearly shows that such a failure is due to the interaction of the BCI sinusoidal current waveform with non-linear devices in RKE electronics, giving rise to non-negligible harmonics in the passband of the RF receiver. Computational electromagnetic simulation (CST EMC Studio) is used to cross check the experimental measurements.

We demonstrated a continuous-wave laser using an anti-reflection coated Cr2+:CdSe crystal with transmission of 98 % at wavelength range from 2.0 to 2.7 μm and with relatively large laser damage threshold of 30 MW/cm2 for the first time. A maximum output power of 1 W at wavelength 2450 nm with an optical-optical efficiency of 48 % and a slope efficiency of 50 % was obtained when the incident pump power was 2.1 W.

Colored c-Si PV cells or modules will allow a wider spread of Building Integrated Photovoltaic (BIPV) both on traditional roofs and on building facades. A few commercial products range from mono or multi crystalline colored PV cells to colored front protecting glasses. In this paper a new colored PV cell structure based on c-Si PV cells is presented and analyzed. Comparison with the simulations of other implemented solutions is also presented and discussed.

In this work, a behavioral model of tubular wave couplers (TWC), whose use was recently included into automotive Standards for immunity verification of wiring harnesses in the frequency range from 400 MHz to 3 GHz, was derived. The model is based on scattering parameter measurements with the TWC mounted onto the calibration structure provided by the manufacturer, and the spurious effects related to such a fixture have been modeled and de-embedded from the measurement data. The proposed behavioral model allows physical insight into the TWC behavior (e.g., device directivity), and represents an important step for possible correlation of the TWC method with radiated susceptibility test procedures foreseen by the Standards.

With the final objective to assure equivalence between radiated and conducted immunity testing to intense electromagnetic pulses, in this work a circuit model of a typical pulsed current injection (PCI) test setup is derived, implemented in SPICE, and validated by measurement. By virtue of such a model, the parameters of the discharge circuit of the pulse generator can be adjusted to compensate the waveform distortion introduced by the injection probe. As proven by an example, the proposed method allows reproducing at the input of the equipment under test a transient disturbance with expected characteristics (i.e., amplitude, rise time, and pulse width).

This paper introduces the control of a photovoltaic (PV) interface converter ready to offer auxiliary service - reactive power control - that also has Phasor Measurement Unit capability. A prototype of the controller is implemented using a National Instruments Compact RIO and tested using Hardware In the Loop techniques. Experimental results demonstrate the converter functionalities.

Frequency-domain current signature analysis for fault detection on induction machines typically requires a very fine frequency resolution to distinguish between spectral components that differ from each other by multiples of the (usually very low) slip frequency. It is well known that if such a high resolution is not achieved, significant leakage errors may arise and misleading diagnostic information can be obtained from the measured current spectrum. This paper presents a leakage error compensation technique that allows accurate results even when the resolution is limited by the requirement of short observation time. This technique is based on the independent knowledge of the frequencies of the relevant components in the spectrum, which only depend on the power supply frequency and on the motor rotation speed, whose measurements are often available. The proposed method is here applied to the detection of rotor bar breakages and it is tested on simulated motor current waveforms.

A multiconductor transmission line model (MTL) is used to investigate the operation of the IEC 61000-4-6 electromagnetic (EM) clamp in a conducted-immunity test setup for aerospace applications. Aspects of interest include the performance of such a coupling device at very high frequencies (up to 1 GHz), and for extreme values of the common-mode impedance of equipment (short circuits, open circuits). The MTL model is finally exploited to predict the frequency response of coupling and decoupling factors defined in the IEC 61000-4-6 standard.