Electromagnetic Emission Measurements Research Articles

Radiated Electromagnetic Emission from Photovoltaic Systems—Measurement Results: Inverters and Modules

Radiated electromagnetic emission of photovoltaic systems, for example, adversely impacting radiocommunication, can pose a major barrier against further increase in photovoltaic penetration. This is particularly the case near sensitive infrastructure and activities such as hospitals, airports, search and rescue, and military. To understand the impact of each component and installation detail, we performed systematic radiated electromagnetic emission measurements on comparable commercial photovoltaic systems in the frequency range 150 kHz to 30 MHz. Our measurements indicate that string inverters are unlikely to interfere with radiocommunication when installed according to recommended standards, rules, guidelines, and regulations. It was shown that module-level power optimizers are the main cause of high levels of radiated emissions. The frameless bifacial module showed higher levels of radiated emissions than the monofacial module with frame. Changes in cable management and earthing have less impact on radiated emissions than the choice of solar inverter concept and module type.

A modular and scalable system for electromagnetic compatibility testing of integrated circuits

To bring automotive integrated circuits (ICs) to market, manufacturers must subject their products to numerous electromagnetic compatibility (EMC) tests such as electromagnetic immunity and emission tests, or electrostatic discharge (ESD) tests. These tests need EMC test boards that meet the requirements of the specific standards. However, the current need to increase the frequency range of EMC tests poses a challenge in designing standard-compliant test boards. In this paper, we address this issue by introducing a modular and reusable IC level EMC test system. We demonstrate the system’s effectiveness with an example of two frequently used and conducted EMC tests: the direct power injection (DPI) immunity test and the 150Ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$150\\,\\mathrm{\\Omega}$$\\end{document} electromagnetic emission measurement. The two test setups are constructed and validated using the presented modules. It is shown how the frequency range can be expanded while minimizing costs and design efforts for the EMC test board design.

Considerations about the measurement of electromagnetic emissions

he main goal of the paper is to present procedures and analysis of the measurement that must be performed and the compulsory results to obtain compliance with conducted and radiated electromagnetic emissions. After the introductory section which outlines generalities related to electromagnetic compatibility (EMC), the second section focuses on the dichotomy between near-field and far-field, present in two important zones where electromagnetic phenomena are totally different, which however are not well enough highlighted in the specific EMC standards. The third section is devoted to emission measurements that must be performed in different electromagnetic environments and for different types of equipment depicted in the specific standards in force. As an example, the case of electromagnetic emissions produced by a household gas thermal power unit is presented.

A review of measurement of electromagnetic emission in electronic product: Techniques and challenges

Nowadays, electronic products are being used extensively in many fields and applications. The dense population of electronic devices in human life has become a challenge for microwave engineers to ensure that their products can meet the Electromagnetic Compatibility (EMC) standards. Complex electronic products with smaller sizes and denser components will be a challenge for compliance with EMC standards. In addition, the occurrence of non-stationary emission at certain operating modes becomes a challenge for analysis. Error in analyzing EM emissions will make the products unable to meet the requirements of EMC standards; hence, they will be prohibited to be marketed. Currently, there are two methods of emission analysis, i.e. by measurement and modeling or computation. There are some problems, however, in the analysis of EM emissions regarding the area of test, complexity, DUT positioning error, installation cost, and time consumption. In this paper, the analysis techniques for EM emissions including Open Area Test Site (OATS), Anechoic chamber, Transverse Electromagnetics TEM Cell, Compact Antenna Test Range (CATR) and near field scanning are reviewed comprehensively. This survey covered EMC standards, principles of EM emission measurement techniques, advantages and disadvantages of EM emission measurement techniques, studies and applications of each technique, recommendations for which technique to be used, and challenges for future research in EM emission measurement. The final section of this paper discusses the challenges for near-field measurements related to the non-stationary emissions phenomenon. This papers also presents the challenges of how to detect and characterize them.

Autonomous Instrumentation for Measuring Electromagnetic Radiation from Rocks in Mine Conditions-A Functional Analysis.

This paper analyses the function of an innovative integrated receiver for the measurement of electromagnetic field emissions. The autonomous receiver measures and registers the elevated emission levels of both components of the EM field originating from rocks subjected to increased mechanical stress. The receiver’s sensitivity of 60 µV/m, its dynamic range of 98 dB, and its impulse response of 0.23 V/µs were determined in laboratory conditions. Real EM field signals from hard coal samples subjected to crushing force were recorded using an autonomous receiver. The observed and recorded results confirm that the receiver operates in the full range of amplitudes of the EM field signal emitted from the rock. The results determine the band of characteristic signals for EM field emission from hard coal. The system created on the basis of autonomous EM receivers can support the existing seismic safety systems in real mine conditions by predicting the possibility of mine collapse hazards.

On the Issues of Spatial Modeling of Non-Standard Profiles by the Example of Electromagnetic Emission Measurement Data

This paper examines the possibility of the spatial modelling of the Earth’s natural pulsed-electromagnetic-field measured values, which form a closed profile without the data inside. This geophysical method allows us to map active tectonic movement which breaches the integrity of pipes. During the experiment, 4.5 km of profiles were measured in the Admiralteysky district of St. Petersburg, Russia. Regular electromotive force (EMF) values and anomalous EMF values were obtained, ranging from 0 to 900 µV and above 900 µV, respectively. The anomalous values are associated with tectonic faults in the bedrock. The data obtained are characterized by complex spatial anisotropy associated with the development of two groups of tectonic faults of different orientations. The authors have considered the problems of the spatial modeling of the data obtained. The main problems, the solutions to which should allow the obtaining of adequate models, have been identified. Based on the analysis of the measurement results, geological features of the studied areas, as well as variography, the following possible solutions were proposed: changing the measurement technique; dividing the data array according to the main directions of anisotropy; the need to introduce additional correction coefficients. The problem revealed in this article requires further research on the basis of the obtained results, which will reduce the cost and timing of such studies, and, as a result, give an opportunity to take into account active tectonic disturbances during the construction and scheduled maintenance of underground utilities, which is especially important within the framework of the concept of sustainable development.

Conducted electromagnetic emissions of compact fluorescent lamps and electronic ballast modeling

<abstract> <p>The higher frequency electromagnetic (EM) emission in low voltage power systems is rising continuously due to the increasing use of modern electronic devices. The electronic ballast of a compact fluorescent lamp (CFL) is one of the sources of conducted EM emission in the power system. Conducted EM emission measurements are performed on compact fluorescent lamps (CFL) in the range of 2–150 kHz and compared with simulation results. The LTSpice simulation of typical 11W compact fluorescent lamps is used to analyze the measured values. Comparisons are made in both the time and frequency domains. The EMI filter in the ballast circuit can reduce the level of high-frequency EM emission. However, in order to get a more accurate result, it is necessary to find out the main cause of conducted EM emission in the ballast circuit, as the HF distortion spreads through the LV network in current signal between electronic devices.</p> </abstract>

Electromagnetic Radiation (EMR) and Human Health: A Study on the Health Effect of EMR from GSM Base Stations in North-Western Nigeria

Nigeria had maintained substantial intensification in the perspective of the mobile communication utilization, services improvement and sustainable broadband regime and this development is presumed to persist into the conceivable future with the evolution of the contemporary 6G, 5G, 4G and 3G mobile communication technologies. The current mobile communication technologies intensification had equally brought the unavoidable multiplications in the ratio of the base service stations which also had raised the public concern over the considerable health hazards of the radioactive emissions from the communication systems. Notwithstanding the assurances of the several regulatory agencies, the World Health Organization and service providers, confirming compliance and strict observance to the international exposure standards in implementation, the apprehension over the electromagnetic spectrum emission is increasing. To that effect, the International Commission on Non-Ionizing Radiation Protection (ICNIRP) had made recommendations that established the intensities of the radio frequency (RF) exposures which are considered harmless to the community of users. This paper assessed the radio frequency radiation from mobile base stations in some selected states in north western Nigeria. The methodology employed for the study is measurement and instrumentation method. Handheld spectrum analyzer (Aaronia HF 4040V3) and a wheel meter were used for the measurement of electromagnetic emissions from selected Airtel, Glo, MTN and Etisalat base stations at capital city of Kano, Jigawa and Katsina states respectively. It was found from the study that 17 to 70mW/m2 is the average electromagnetic radiation emitted in the study area, which showed total compliance of exposure limit by the GSM service providers in the selected states. The result confirmed the environmental safety level of the RF energy maintained within the general public and that are predictably low to produce any significant health hazards to human.

High-Frequency Characterization and Parametrized Modeling of DC-Biased Surface-Mount Ferrite Beads for EMI Suppression Applications

Circuit models of ferrite beads used for electromagnetic (EM) noise filtering are important for prediction and effective reduction of EM noise on power or signal lines. A methodology for impedance characterization and modeling of surface-mount ferrite beads is proposed in this article. The presented methodology combines series and shunt characterization methods to extract the equivalent circuit model of ferrite beads. The extracted models consist of frequency-independent elements and they are valid up to 1 GHz, to cover the bandwidth required by the EM compatibility standards for measurements of EM emissions. The values of the lumped elements of the extracted model are optimized to fit the measured impedance characteristics for each ferrite bead at bias current levels up to 5 A. Finally, the values of the lumped elements are parametrized with respect to the bias current from 0 to 5 A and the normalized error of the model compared to the measurements is calculated and found to be less than 10 $\boldsymbol{^{\mathrm{-3}}}$ .

Multi-frequency SuperDARN radar observations of the modulated ionosphere by high-power radio-waves at EISCAT

This paper presents the first joint observations of multi-frequency SuperDARN (Super Dual Auroral Radar Network) radar of the heated ionosphere by high-power high-frequency (HF) ground-based radio-waves along with the stimulated electromagnetic emissions (SEE) measurements. The unique heating experiment design at EISCAT (The European Incoherent Scatter Scientific Association) including fine frequency stepping through the fourth electron gyro-frequency (4fce) provided the opportunity to directly determine the plasma waves responsible for SuperDARN radar echoes. Past experiments using a unique Kodiak SuperDARN receiver in Alaska with capability of data recording over a large bandwidth of frequencies different from the radar transmission frequency was able to detect some radar echoes due to pump-excited plasma waves. However, a precise characterization of these waves could not be reached in the past. Comparison of the behavior of the SEE data measured on the ground besides the multi-frequency SuperDARN observations above the heated ionosphere at EISCAT has shown a good correlation with the characteristics of upper-hybrid (UH)/electron Bernstein (EB) waves excited through parametric decay instability. The ray tracing model based on the EISCAT dynasonde data of the background ionospheric parameters has been used in order to determine the natural ionospheric effects on the propagation path of 9.9 MHz, 13.2 MHz, and 16.6 MHz signals associated with SuperDARN radar. By providing a more direct connection between SuperDARN echoes and the associated SEE measurements, this new technique potentially provides more quantitative characterization of plasma waves generated during ionospheric heating.

Measurement of Electromagnetic Field Component Emissions as a Precursor of Emerging Hazard in Coal Mines

The article presents the results of research concerning electromagnetic (EM) field emitted by rocks during the process of their destruction. The paper describes a measuring stand designed for subjecting rock samples to axial crushing. During the destruction of rock samples, both components of the electromagnetic field emitted by the rock were recorded. The paper presents the results of research on hard coal samples, presenting the obtained time domain waveforms and frequency spectrum of the emitted EM field components. Further potential uses of tests concerned with EM emitted by rocks are determined. Applications registering EM field in mine environments may provide an early mine collapse warnings.

Measurement of Near-Field Electromagnetic Emissions and Characterization Based on Equivalent Dipole Model in Time-Domain

In this article, a method for representing electromagnetic emissions from a device under test (DUT) using an equivalent time dependent dipole array model deduced from the time-domain near-field scanned tangential magnetic fields is proposed. First, a three-dimensional (3-D) time-domain near-field scanning system is established to measure the tangential magnetic fields emitted from DUTs which are a transmission line above a ground plane and a printed circuit board (PCB) with several microstrips, respectively. For time-domain measurements, two magnetic field probes are calibrated over a broad bandwidth for both amplitude and phase to obtain their complex probe factors. Then, the measured magnetic fields are utilized to construct an equivalent time dependent dipole array model to represent the electromagnetic sources of the DUT. Parameters of the time dependent equivalent dipoles are directly calculated by fitting to the measured magnetic fields. The effects of different number of dipoles on the accuracy of the reconstructed magnetic fields from the PCB are studied. The reconstructed equivalent dipoles of the DUTs can be used to predict the electromagnetic fields at other observation levels. The results predicted by the equivalent dipole model are in agreement with the simulated and measured results.

Stochastic electromagnetic field propagation- measurement and modelling.

This paper reviews recent progress in the measurement and modelling of stochastic electromagnetic fields, focusing on propagation approaches based on Wigner functions and the method of moments technique. The respective propagation methods are exemplified by application to measurements of electromagnetic emissions from a stirred, cavity-backed aperture. We discuss early elements of statistical electromagnetics in Heaviside's papers, driven mainly by an analogy of electromagnetic wave propagation with heat transfer. These ideas include concepts of momentum and directionality in the realm of propagation through confined media with irregular boundaries. We then review and extend concepts using Wigner functions to propagate the statistical properties of electromagnetic fields. We discuss in particular how to include polarization in this formalism leading to a Wigner tensor formulation and a relation to an averaged Poynting vector.This article is part of the theme issue ‘Celebrating 125 years of Oliver Heaviside's ‘Electromagnetic Theory’’.

Electromagnetic field generated by a wireless energy transfer system: comparison of simulation to measurement

This paper presents a wireless energy transfer system operating at the frequency values of kHz order: modeling, simulation, and comparison with prototype measurement results. Wireless energy transfer system model using finite element method was carried out to simulate the electric field and the magnetic flux density for different air gap sizes between the transmitter and the receiver coils. Results are presented and compared with the electromagnetic emission measurements radiated by the wireless energy transfer system prototype. The electric field comparison between the simulated and the prototype measurement values shows an error of roughly 8.7%. In the recent years, the interest in the wireless energy transfer technology, especially for electric vehicles batteries charging, is rapidly increasing. As a result of the increasing application of this technology in the industrial and consumer electronic products, more concerns are raised about the electromagnetic compatibility, since the wireless energy transfer systems produce electromagnetic emissions in the surrounding environment.

Identification of Non-Stationary Magnetic Field Sources Using the Matching Pursuit Method

The measurements of electromagnetic field emissions, performed on board a vessel have showed that, in this specific environment, a high level of non-stationary magnetic fields (MFs) is observed. The adaptive time-frequency method can be used successfully to analyze this type of measured signal. It allows one to specify the time interval in which the individual frequency components of the signal occur. In this paper, the method of identification of non-stationary MF sources based on the matching pursuit (MP) algorithm is presented. It consists of the decomposition of an examined time-waveform into the linear expansion of chirplet atoms and the analysis of the matrix of their parameters. The main feature of the proposed method is the modification of the chirplet’s matrix in a way that atoms, whose normalized energies are lower than a certain threshold, will be rejected. On the time-frequency planes of the spectrograms, obtained separately for each remaining chirlpet, it can clearly identify the time-frequency structures appearing in the examined signal. The choice of a threshold defines the computing speed and precision of the performed analysis. The method was implemented in the virtual application and used for processing real data, obtained from measurements of time-vary MF emissions onboard a ship.

Determination of Crack Surface Orientation in Carbon Fibre Reinforced Polymers by Measuring Electromagnetic Emission

Electromagnetic emission (EME) generated by fracture of carbon fibre reinforced polymers (CFRP) is studied. The fracture is induced to cross-ply CFRP by mechanical loading in a three-point bending configuration. An EME acquisition set-up operating on the principle of capacitive coupling is used to measure the low frequency (kHz-MHz range) electric field whose generation is attributed to the charge redistribution accompanying the fracture processes. Multiple, differently oriented EME sensors, for the simultaneous EME measurement with different source-sensor orientations, were applied to account for the directionality of the EME sources and their generated electric fields. A method to deduce the crack orientation based on the emitted EME field’s directionality is proposed. A comparison between the angles of the EME sources obtained by this method and the actual crack surface orientations as determined by computed tomography is made.

Measurement and Study of Electromagnetic Emission Generated by Tensile Fracture of Polymers and Carbon Fibres

Electromagnetic emission (EME) signals generated by tensile fracture of four different types of polymers and three different carbon fibre types are presented and discussed. A suitable set-up for the detection of the electric field component of EME generated by fracture of solids is proposed. Basic theoretical considerations are made about the coupling between these field components and the capacitive sensors used to directly measure the short ranged and low frequency (kHz–MHz) electric fields emitted by the generation of free surface charges and their spatial movement as dictated by the vibrational motion of the crack walls. Special focus is put on solids with low conductivity, where the influences of the material on the emitted fields is small and the detected electric signals almost solely depend on the source dynamics and the sensor characteristics. Analysis of the influence of the acquisition circuit is presented. The discussion of the electric signals emitted by tensile fracture of carbon fibres and polymer specimens comprises the influences of the material properties on the signals as well as correlations between the signals and the crack dynamics, including the crack propagation velocities.

Field Measurement of Natural Electromagnetic Emissions near the Active Tectonic and Mass-Movement Fractures in Caves

Laboratory tests on a wide range of solid materials shoved that the electromagnetic emission (EME) signals are generated during the samples mechanical stress. EME anomalies have been observed also under natural conditions in association to fracture processes, tectonic loading, stress redistribution and crack propagation prior to earthquake or in relation to deep-seated gravitational mass movements. This paper describes a first prototype of the Emission data logger, which was specially developed for the continual EME monitoring in field conditions. Our equipment has been installed and tested in Obir Caves (Austria) at an active tectonic fault. The pilot long-term EME measurement results from this location are also presented in this paper.

전기자동차 충전구 위치에 따른 전자파 방사특성에 관한 연구

According to revolutionary developments in automobile technologies, eco-friendly advanced vehicles (hybrid vehicle, hydrogen fuel-cell vehicle, electric vehicle, etc.) are rapidly increasing. The electromagnetic compatibility is getting more important for development of a vehicle because those advanced vehicles are driven by electric energy and equipped with more electric systems. In general, electromagnetic compatibility tests consist of an electromagnetic interference(EMI) test and an electromagnetic susceptibility(EMS) test. EMI test of the electric vehicles are needed not only in driving mode but also in charging mode because they must be recharged by much electric energy for driving. Depending on vehicle manufacturers, the charging device type and the location of charging device inlet in electric vehicles are various. In this paper, in order to investigate EMI of electric vehicles in charging mode in consideration of the direction of measuring antenna and the location of charging device inlet, a series of electromagnetic emission tests are conducted using three electric vehicles (neighborhood electric vehicle, electric vehicle and electric vehicle-bus). The test results show that electromagnetic emission measurements in charging mode are dependent on the direction of measuring antenna and the location of charging device inlet.

Wideband Conducted Electromagnetic Emission Measurements Using IPD Chip Probes

A novel on-chip measurement technique for characterizing conducted electromagnetic emission of integrated circuits in the gigahertz frequency range is proposed. The International Electrotechnical Commission (IEC) direct coupling method is reviewed, and the considerations on improving the applicable bandwidth of the testing probes are discussed. Design of the most critical resistive components for the probes is elaborated to achieve the required accuracy and bandwidth. With the compact chip probes realized by the integrated passive device (IPD) technology, the measurement bandwidth can be significantly extended compared with the conventionally used surface mounted device resistors. The probes are verified to comply with the IEC 61967-4 standard, and an excellent bandwidth up to 15 GHz can be achieved. By connecting the flipped die under test with the probes embedded in IPD substrate (core sizes of the 1- $\Omega $ current probe and 150- $\Omega $ voltage probe are $0.55~\text {mm}\times 0.77$ mm and $0.83~\text {mm}\times 1.49$ mm, respectively), the conducted emission measurement of a 58-MHz oscillator integrated circuit is demonstrated up to 3 GHz.