Electromagnetic Compatibility Issues Research Articles

Full-Field Displacement Measurement Method of Metal-As-Insulation Pancake at Liquid Nitrogen Temperature

In situ measurement of metal-as-insulation (MI) high temperature superconductor (HTS) pancake deformation gives insight to its actual mechanical state. Measurement of hoop strain for inner / outer turn of MI pancake is usually made by strain gauges. This measurement is however local and faces electromagnetic compatibility (EMC) and thermal issues. Non-contact full-field displacement measurement is an interesting alternative solution. This technique is based on digital image correlation (DIC), which derives the displacement field in specified region of interest (ROI) by correlation between the deformed state image and the reference state image. In this article, we present a novel DIC experiment setup for displacement measurement of MI pancake in cryogenic cooling. The setup is validated by a cooling test of 304 stainless steel disc. Then, it is used for cooling test of MI pancake made of co-wound copper beryllium - 304 stainless steel tapes. Both tests are done at 80 K by conduction cooling using liquid nitrogen. Finally, experimental results are compared to numerical results obtained from an analytical formulation of the mechanical equilibrium using generalized plane strain assumption.

Synthesis, Control, and Excitation of Characteristic Modes for Platform-Integrated Antenna Designs: A design philosophy

Electrically compact antennas that exploit the characteristic modes (CMs) of their platforms have recently attracted much attention in military and terminal device antenna research. Conventionally, to design an antenna on a platform, the antenna element is first synthesized in a stand-alone manner, without explicitly considering the platform structure. Electromagnetic compatibility issues may arise since the size of the antenna is usually comparable to the wavelength of operation. In contrast, CM-based platform-integrated antenna design takes advantage of the natural resonant modes of the platforms to achieve the desired properties, such as multiband/wideband operation, polarization or pattern reconfigurability, high isolation between ports (in the case of multiport antennas), and achievement of the specified gain.

A Closed Form Selected Mapping Algorithm for PAPR Reduction in OFDM Multicarrier Transmission

Nowadays, the demand for communication multi-carriers’ channels, where the sub-channels are made mutually independent by using orthogonal frequency division multiplexing (OFDM), is widespread both for wireless and wired communication systems. Even if OFDM is a spectrally efficient modulation scheme, due to the allowed number of subcarriers, high data rate, and good coverage, the transmitted signal can present high peak values in the time domain, due to inverse fast Fourier transform operations. This gives rise to high peak-to-average power ratio (PAPR) with respect to single carrier systems. These peaks can saturate the transmitting amplifiers, modifying the shape of the OFDM symbol and affecting its information content, and they give rise to electromagnetic compatibility issues for the surrounding electric devices. In this paper, a closed form PAPR reduction algorithm is proposed, which belongs to selected mapping (SLM) methods. These methods consist in shifting the phases of the components to minimize the amplitude of the peaks. The determination of the optimal set of phase shifts is a very complex problem; therefore, the SLM approaches proposed in literature all resort to iterative algorithms. Moreover, as this calculation must be performed online, both the computational cost and the effect on the bit rate (BR) cannot be established a priori. The proposed analytic algorithm finds the optimal phase shifts of an approximated formulation of the PAPR. Simulation results outperform unprocessed conventional OFDM transmission by several dBs. Moreover, the complementary cumulative distribution function (CCDF) shows that, in most of the packets, the proposed algorithm reduces the PAPR if compared with randomly selected phase shifts. For example, with a number of shifted phases U=8, the CCFD curves corresponding to the analytical and random methods intersect at a probability value equal to 10−2, which means that in 99% of cases the former method reduces the PAPR more than the latter one. This is also confirmed by the value of the gain, which, at the same number of shifted phases and at the probability value equal to 10−1, changes from 2.09 dB for the analytical to 1.68 dB for the random SLM.

Expected electromagnetic environment at the energy infrastructure facilities of remote ports (berths)

The article deals with the issues of electromagnetic compatibility of coastal and floating objects in the waters of ports (berths). The subject of the study is the processes occurring in the electrical network when powering ships of the technical fleet and floating objects from the shore, which determine the need for automated calculation of conductive low-frequency electromagnetic disturbance for their subsequent suppression. An algorithm for calculating the parameters of the electromagnetic environment is presented, which is based on the analysis of the distribution parameters of slow voltage changes. The mechanism of EMD occurrence in voltage deviation is described and a mathematical model explaining the probability of its occurrence is presented. An algorithm for calculating the parameters of the electromagnetic environment based on slow voltage changes in the network is compiled. This algorithm is implemented in the “Program for the study of slow voltage changes by the load changingof the electrical network ". For the object under study, the parameters of the distribution of conductive low-frequency electromagnetic disturbance over a slow voltage change are determined. A block diagram of an automatic voltage regulator implementing the proposed voltage stabilization law has been developed.

Development of a Magnetic Field Probe for Near-Field Measurement

Current electronic circuits are characterised by their compact design of miniaturisation; however, such a feature has also contributed to the rise of electromagnetic compatibility issues. This study introduces a technique to develop a magnetic field probe for near-field measurement. The probe aims at performing the debugging of electromagnetic interference on an integrated circuit. Certain processes, such as designing a microstrip line in simulation and a prototype for the validation as well as developing a functional magnetic field probe for near-field scanning and calibration measurement to determine the probe factor, have been performed under a frequency domain. The microstrip line model is built both as a simulation and a real prototype, and the handcrafted loop probe is developed with the same diameter as a commercial probe. Calibration measurement is set-up with a vector network analyser (VNA) to capture the magnetic field on radiated plane. The performance of the handcrafted probe in terms of measuring the configuration of the H-field source on the scattering region is conducted. Two types of measurements which are S11 and S21 will be conducted using a VNA. The comparison of the S11 and S21 results against simulation results are plotted using MATLAB. S11 represents the return loss of the microstrip line while S21 represents the power received by the magnetic field probe relative to power input to the microstrip line. The results of the S11 parameter indicate that the customised microstrip line board has a similar waveform pattern that matches the one on the simulation model. The S21 results for the handcrafted probe revealed that it can only function well up to the frequency of 2.644 GHz, the abnormal result obtained after the frequency mentioned. Some factors may have affected the results, such as material loss, fabrication tolerance and interferences from other devices. Therefore, calibration measurement is conducted under a less reflected radiation environment, and the designated substrate should be a perfect material correlated with the measurement.

Improving the electromagnetic compatibility of electronic products by using response surface methodology and artificial neural network

PurposeThe purpose of this study is to use the Taguchi Method for parametric design in the early stages of product development. electromagnetic compatibility (EMC) issues can be considered in the early stages of product design to reduce counter-measure components, product cost and labor consumption increases due to a number of design changes in the R&D cycle and to accelerate the R&D process.Design/methodology/approachThe three EMC characteristics, including radiated emission, conducted emission and fast transient impulse immunity of power, are considered response values; control factors are determined with respect to the relevant parameters for printed circuit board and mechanical design of the product and peripheral devices used in conjunction with the product are considered as noise factors. The optimal parameter set is determined by using the principal component gray relational analysis in conjunction with both response surface methodology and artificial neural network.FindingsMarket specifications and cost of components are considered to propose an optimal parameter design set with the number of grounded screw holes being 14, the size of the shell heat dissipation holes being 3 mm and the arrangement angle of shell heat dissipation holes being 45 degrees, to dispose of 390 O filters on the noise source.Originality/valueThe optimal parameter set can improve EMC effectively to accommodate the design specifications required by customers and pass test regulations.

A novel dynamic integral sliding mode control for power electronic converters.

The key characteristics of the sliding mode control (SMC) are the ability to manage unmodeled dynamics with rapid response and the inherent robustness of parametric differences, making it an appropriate choice for the control of power electronic converters. However, its drawback of changing switching frequency causes critical electro-magnetic compatibility and switching power loss issues. This paper addresses the problem by proposing a dynamic integral sliding mode control for power converters having fixed switching frequency. A special hardware test rig is developed and tested under unregulated 12.5-22.5 V input and 30 V output. The experimental findings indicate excellent controller efficiency under wide range of loads and uncertain input voltage conditions. In addition, the findings indicate that the closed-loop system is robust to sudden differences in load conditions. This technique provides an improvement of % in the rise time, % in the settling time and % in robustness of the controller as compared to conventional controllers. Furthermore, the comparison with the existing fixed-frequency sliding mode control techniques is presented in a tabular form.

Reduction in Transmission Power of Base Transceiver Station

Nowadays mobile usage is the essential need of humans. To provide the mobile network services, the Telecommunication companies propose the installation of Base Transceiver Station over large populated and industrial areas. The radiations emit from these BTS may give rise to various electromagnetic and ecological compatibility issues [1]. The radiation power of these BTS is up to 5-10 KiloWatts (up to 320-350 W per channel), which can be detrimental for the human beings, if they are installed in populated areas. The purpose of this paper is to reduce the transmission power of the BTS which is possible through the usage of Self-phased array antenna. Self-phasing array antenna through the use of pilot carrier in Telecommunication systems can degrade the Tx upto10-20dB

Data-driven relative position detection technology for high-speed maglev train

High-speed maglev train speed measurement and positioning system is the basis of train traction and operation control. The existing relative position based on the principle of electromagnetic induction is vulnerable to electromagnetic interference and suspension gap fluctuations, which requires a lot of time to solve electromagnetic compatibility and other issues. In this paper, a data-driven relative position detection scheme based on laser displacement sensor combination is proposed for the high-speed maglev train speed measurement and positioning system. It uses a combination of laser displacement sensors to collect the vertical displacement signal and establishes the relative position detection model of one coggle cycle by designing a neural network to sense the periodic change of vertical displacement signal, which effectively overcomes the influence of suspension gap fluctuation. In order to improve the modeling accuracy, an adaptive fault-tolerant filtering algorithm is proposed, which can effectively overcome the effects of inconsistent width of the long stator surface, inconsistent depth of the stator cable depression, and foreign bodies on the stator surface. At the same time, the proposed scheme can determine the rail gap in real time, through the two detection signal switching mode can eliminate the influence of rail gap. The analysis and experimental results show that the proposed solution can effectively adapt to various conditions of vehicle operation, overcome the influence of electromagnetic interference and suspension fluctuations, and realize the high-precision positioning requirements of high-speed Maglev trains.

A Contribution to Safe Railway Operation: Evaluating the Effect of Electromagnetic Disturbances on Balise-to-BTM Communication in Railway Control Signaling Systems

Electromagnetic (EM) disturbances and compatibility issues are the most common problems affecting communication and signaling systems. The duration of field testing to solve these railway EM interference (EMI) problems may vary between three and 12 months, with the cost of the complete process between €25,000 and €1.5 million [1]. Currently, the railway industry demands the building of strategies and tools to promote paths toward zero on-site testing [2] and reduce the duration of field tests; however, there is a lack of laboratory testing resources for these approaches.

Issues Concerning Determination of Impulse Voltage, Current, and Impedance

The paper deals with satisfying the quasi-stationarity (or quasi-static) condition in studies of impulse quantities. The validity of the definition of voltage, current, and immittance is discussed. Examples are given regarding the electromagnetic compatibility issues when the quasi-stationarity condition is not met, thus the basic electric circuit quantities are not uniquely defined.

Conducted Emission Suppression Using an EMI Filter for Grid-Tied Three-Phase/Level T-Type Solar Inverter

Electromagnetic interference in power converters is a crucial problem for circuit designers. Electromagnetically compliant converter design is required for the safety of an operation. A novel filter design approach considering ground leakage current, different winding styles for common mode choke, tolerance of filter capacitor is proposed in this study to solve the electromagnetic interference problem. In the study, electromagnetic compatibility issue is investigated for a 25 kW, 15 kHz switching frequency, three-phase/level T-type grid-connected solar inverter. The test setup is installed based on EN55011 standard, and the interferences emitted by the inverter to the grid through conduction are measured. Then, a filter design is made to prevent these interferences from being transmitted to the grid. After the filter is designed and engaged, the measurements are repeated. So, the noise attenuation of the EMI filter is verified experimentally. Experiences obtained from the hardware modification in the EMI filter, which is designed for an industrial solar inverter, have been discussed. It is observed that the result of conducted emission measurement is within the limits of the EN55011 Class B standard.

Advances in Computational Modeling of EMC/EMI Effects in Communication-Based Train Control (CBTC) Systems

Communication-based train control (CBTC) systems are aimed at providing control and signaling for rail transportation. These operate in environments that include tunnel and open-air sections, as well as busy stations, coexisting with Wi-Fi and cellular communication networks. Modeling electromagnetic compatibility and interference (EMC/EMI) issues in CBTC is most efficiently achieved by hybridizing several computational electromagnetic techniques rather than relying on a single one. This paper presents an overview of the applicable standards and some typical EMI scenarios for CBTC systems. Then, we discuss recent advances in hybridizing the vector parabolic equation (VPE) method, ray-tracing (RT) and the finite-difference time-domain (FDTD) technique, towards the efficient modeling of such scenarios.

Вопросы радиочастотного обеспечения космических систем на основемногоспутниковых группировок с учетом требований МСЭ-R и результатов ВКР-19

Deployment of space systems based on multi-satellite constellations to provide broadband Internet access and communication services acutely raises the question of their radio frequency support including issues of electromagnetic compatibility (EMC) between competing space systems using multi-satellite constellations (StarLink, OneWeb, Kuiper, etc.), their EMC with traditional space systems (satellite communication systems that employ spacecraft in geostationary and non-geostationary orbits, space systems of other services), as well as regulatory issues of entering into service and staged deployment of space systems. The article formulates the problematic issues of radio frequency support of modern space systems taking into account the trends of satellite constellations deployment and proposes the solutions with consideration to international and national requirements in the regulation of radio frequency spectrum including the ITU requirements and the requirements of Russian State Commission for Radio Frequencies. The paper shows the ways to share the radio frequency spectrum to meet new requirements of the World Radiocommunication Conference 2019 (WRC-19).

Electromagnetic compatibility issues in hybrid wired and wireless industrial networks.

Industrial networks are currently the only communication means designed for real-time systems used in industry. Networked control systems (NCS) are still important and commonly used type of such systems operating on shop floor. As a computerized node of NCS, a programmable logic controller (PLC) is usually used. In most cases, contemporary devices of such kind are equipped with more than one network interface of various types. Typically, only one interface is activated in NCS. Sometimes, the other is used for communication between NCS and supervisory systems. Occasionally, it is additionally involved in the data transmission in the factory IT systems. In general, however, using a single network interface is a more common solution. In this paper, the mutual utilization of more than one interface is discussed in order to back up the NCS network and to manage the node-related traffic within the scope of higher level services. The question of dependability of such a system from the electromagnetic compatibility point of view is discussed. The example is provided based on Profinet via wired and wireless connection.

Densely-Packed Construction for Hybrid Power Control System for Unmanned Aerial Vehicles

This paper examines the creation of the hybrid power control system with dense layout of units for the various vehicles. The relevance of the topic is proved by the several publications of Toyota Motors, Subaru Corporation, Texas Instruments and others, who have implemented similar decisions in their electronic control units. The mathematical model and the developed prototype are suitable for gasoline internal combustion engine, where the main feature of this development is the support and control of energy generation. Due to the dense layout of particular vehicles it is necessary to resolve the issues of electromagnetic compatibility, based on protection and decoupling of various elements among themselves. The controlling device for the internal combustion engine of vehicle carries out a complete decoupling of control and signal circuits, and protection of power for integrated circuits. These constructive decisions include the installation of optically decoupled devices, protective diodes and resistances for bypassing the high voltage surges. The proposed concept includes the control of the engine cooling, ignition, engine rate and throttle, generation current, engine startup and cut-off. The prototype working on this concept has an increased uptime and working distance. These features ensure the stability of the engine and its primary characteristics of rate support and generation current control. Processes of installation prototype modeling, technical decisions and reliability issues have been described. This work can be used to develop the engine control units with high reliability and diverse set of functions.

Electronic safety systems used on a vast railway area – operational problems

The article presents issues related to the use of electronic security systems (ESB) on a vast railway area. These systems are operated in very different environmental conditions. Due to the fact that electrical and electronic systems coexist on the extensive railway area for various purposes - e.g. power supply systems for railway traction, rail traffic control systems (SRK), electronic security systems - fire alarm system (SSP), CCTV system (CCTV), access control system (SKD), a significant operational problem in addition to environmental changes in which the above-mentioned technical facilities are used, there is also the issue of electromagnetic compatibility. Depending on the area extent of the railway area, construction, technical configuration, way of alarming, safety classes of these systems may be different. In SSP there is another factor that affects the configuration of these systems, namely the so-called fire scenario and how to notify the State Fire Service (PSP) about an existing fire risk or damage. There are several different ESB structures - focused, distributed and mixed. The type of ESB used in a given railway facility - construction or open area is conditioned by its cubic capacity [m3], terrain extent [m2 or km2] and the number of supervised facilities. The use of a given type of ESB to ensure safety and fire protection in a given railway area also depends on the requirements of legal provisions for the object(s), the fire scenario that must be implemented by the system, legal requirements for the given protected area, the accepted scope of protection and the reliability and operational requirements to be met by these installations. The article presents basic issues related to ESB operation that are used in the selected railway area. The review of technical solutions of selected ESBs and the methodology of conducting the analysis for the purposes of developing, e.g. fire scenario or hazard analysis, presented in the article, will enable railway facility designers to properly develop design assumptions.

Full-Bridge Converter with Soft Commutation in All Load Range

The development of converters with soft commutation improves issues of radiation interference and electromagnetic compatibility, reduce weight and size parameters by increasing efficiency and conversion frequency. A significant reduction in commutation losses allows the use of high-power IGBT modules at higher frequencies which they are not able to withstand in traditional converters with pulse-width commutation.

Proper Equipment Ordinance for Achieving EM Cleanliness in Space Missions: The Case of ELF Electric Sources

A constant electromagnetic compatibility issue in the majority of space missions is the accurate EMI source identification and modeling. This is necessary in order to provide electromagnetic (EM) cleanliness in a specific area inside or outside the spacecraft, where sensitive measurement equipment is placed. Authors in previous work have presented a stochastic process capable to accurately predict the EM signature of a device both for transient and steady-state emissions. In this article, a supplementary methodology is proposed, using the models from the previously established process, to achieve electromagnetic cleanliness. Authors claim that EM cleanliness is possible to be achieved inside or outside a specific area of the spacecraft structure with proper equipment ordinance and if necessary the aid of an additional auxiliary source. The proposed methodology is using a heuristic approach to find the optimum positions of the available equipment. The equipment when placed at these positions presents a minimum total electromagnetic field at a specific point or region. Moreover, if necessary, the total field can be further minimized with the addition of an auxiliary source.

Direction Finding Techniques in Reactive Near Field of Impulsive Electromagnetic Noise Source Aiming at Pantograph Arcing Localization

Pantograph arcing is well known to have several detrimental effects, including electromagnetic compatibility issues. In this paper, we proposed to use direction finding techniques utilizing only two magnetic field components to determine the location of the arcing occurrence independent of weather conditions and with low computational load. Two techniques suitable for impulsive electromagnetic noise in reactive near field are presented. One is well known in the literature and another, which is based on the absolute value of the Poynting vector, is proposed here for the first time. Experiments with an electrostatic discharge gun in a semi-anechoic chamber were used to validate the new technique and to estimate the accuracy of both for pantograph arcing localization.