Experimental study of electromagnetic coupling between two transmission lines

This contribution introduces the education of EMC at the University of West Bohemia in Pilsen (UWB). The phenomenon of Electromagnetic compatibility (EMC) has been taken into account almost at all faculties of electrical engineering in the Czech Republic. However there often are only partial mentions of EMC in frame of individual electrical engineering subjects and the education is focused on the one specific EMC area. At the Faculty of Electrical Engineering at the UWB we have paid attention to these questions in several special subjects in the bachelor and master studying programs. In this paper the education system of the Faculty of Electrical Engineering has been presented. The main attention has been given to the low frequency interference of power electronic converters.

This research was developed in the Master in Education of the Federal University of Uberlândia, in the period 2001/2002, with the objective of analyzing the knowledge and practices failures in the teaching-learning process of the Electrical Engineering course at UFU, with a focus on understanding the forms, meaning and function of evaluative practices in failures in the context of the subjects surveyed (students, teachers); seeking to apprehend the relationship between social representations about this phenomenon and its repercussions on the interactions between teacher and student, in the teaching-learning process and in the perpetuation or transformation of educational practices carried out in the Electrical Engineering course at UFU. It is a research with an emphasis on qualitative aspects, but which contains many quantitative data that served as a subsidy for the choice of the interviewed subjects, of the researched aspects, and to present the failure rates in the period from 1997 to 2001 in a more systematic way , referring to the disciplines common to the two emphases existing in the course: Electronics and Electrotechnics. The interviewed subjects were eight students who had already taken the five subjects that presented the highest failure rates in the defined period, which are: Electromagnetism, Material Mechanics, Electrical Circuits 1, Differential and Integral Calculus 3 and Electrical Materials 1; and three teachers from those same disciplines. In the interviews, in the However, the focus was not only on the five disciplines mentioned, because what was sought to understand and analyze in a more approximate way was the factors that caused the failures, without specifying any discipline. It was based on the assumption that there were ideas, attitudes, behaviors produced in the space socially shared by the group and that these circulated and strongly influenced the perpetuation of failures, which is characteristic of a social representation. To better understand the phenomenon of failures, a historic rescue of the Faculty of Electrical Engineering at UFU was carried out, engineering education and training was discussed in general and a study on learning assessment. The analyzes developed here show that the facing the problem of failures in the Electrical Engineering course at UFU, as well as engineering courses at other institutions implies improving the teaching-learning process learning and training of engineering teachers. It also implies the need for a dynamic and global understanding of the context and everyday life of the course, in order to break with those conservative and authoritarian views, attitudes and practices that favor the perpetuation of phenomena such as failures, and that generate passivity and conformism. between teachers and students.

Contribution: This work evaluates the role of the complementary training programs (CTPs) offered by the Center for Research and Development in Electronic and Information Technology (CETELI), from the Federal University of Amazonas, Brazil. This analysis highlights the relevant role of the CTP, carried out by CETELI, in supporting students in the engineering undergraduate course, thus reducing dropouts and improving retention of low-income students. Background: The great challenge of engineering courses and of all courses in the technological area is to keep in step with the job market and, thus, provide better conditions for entering trainees. Intended Outcomes: Based on the experience of this work, other electrical engineering courses should be encouraged to adopt partnerships with industries, offering the possibility for students to carry out project activities on topics of interest to industries and, especially in developing countries like Brazil, to associate this activity with the provision of scholarships. Application Design: The evaluation assesses the impact of the various CTP partnership projects (PPs) on the graduation rate (GR), on students’ academic performance, and on the average graduation time (GT). It also assesses how the CTP students entered the job market, measuring whether the CTP facilitated their entry. Findings: It was observed a difference in the GR between the students who participated in the CTP and students that did not participate in the CTP. For the computer engineering course, this rate was about five times higher. It was observed that more than half of the students who participated in the CTP entered the market and were hired almost immediately for work in their area of training.

The paper presents the results of a study, conducted in January 2021, that aimed to evaluate progress in training and developing skills and abilities in technical education and to identify the constraints that persist in this important sector of education. Eighteen students enrolled in master's studies in the study program Power Quality and Electromagnetic Compatibility in Electrical Systems (CECESE) and Energy Systems (SEI), from the Faculty of Electrical Engineering in Craiova have participated in the study. They answered a questionnaire with open and closed questions. The main objective of this study was to find out the opinion of the graduates of the Faculty of Electrical Engineering from Craiova from the study program Electrical and Computer Engineering and Power Systems Engineering, about the importance and efficiency of some of the studied disciplines and whether these disciplines had a strong impact on acquiring and improving technical skills, necessary in the activity of electrical engineer. The main findings of the study refer to the methodologies and practices for assessing the level of training and skills development, the receptivity of the educational system to the changes that occur in modern education. The main recommendations of the study concern the curriculum development.

The analysis of the problems of electromagnetic compatibility (EMC) of multi-user information and communication systems (ICS), using code division as a way of providing multiple subscribers access to system resources, in which each subscriber occupies the entire frequency band and the entire time interval. It is shown that the problem of electromagnetic compatibility of ICS as the possibility of a conflict-free existence of various wireless ICS in the conditions when each of these systems has the ability to receive its signals and signals of other systems is one of the highest priorities in the design and operation of such systems. It is shown that EMC requirements can be realized through the use of broadband noise-like signals (BNLS) as synchronization signals and signals – physical data carriers under various interfering influences, including narrow-band, wide-band obstruction, intrasystem (imitated, relayed) and other interferences caused by neighboring stations. This possibility is provided due to the use of signals with a large value of the time-frequency product (signal base) without increasing the signal duration and peak radiation power. Based on the use of the criterion of distinguishability of the signals of the minimum root mean square distance between the signals (vectors), the requirements for the synthesis and selection of the BNLS classes are formulated to ensure that the EMC requirements of multi-user wireless communication systems are met. A new class of complex nonlinear discrete cryptographic signals is proposed as data carrier signals and synchronization signals. It is shown that the use of such signals, due to the fact that they have improved ensemble, correlation, and structural properties, will allow for a comprehensive solution to the EMC problem of modern ICS.

The purpose of this study was to determine the effectiveness of using Virtual Reality-Based virtual laboratories on student learning outcomes in the Internet of Things Course in the Electrical Engineering Study Program, the average difference in student learning outcomes through the use of Virtual Reality-Based virtual laboratories in the Internet of Things Course in the Engineering Study Program Electrical Engineering, and student learning motivation through the use of Virtual Reality-Based virtual laboratories in the Internet of Things Course in the Electrical Engineering Study Program. This research is an experimental research approach that will be used is Quasi Experimental Design with the form of Nonequivalent Control Group Design. The validation test was carried out by measurement experts for post-test and pre-test questions, each aspect was tested by two experts. The results of the study show the effectiveness of using Virtual Reality-Based virtual laboratories to improve student learning outcomes in the Internet of Things Course in the Electrical Engineering Study Program. The increase in student learning outcomes analyzed using N-gain in the experimental class obtained an average value of 0.65 including the medium category, and the average N-gain for the control class was 0.15 in the low category. Meanwhile, the average difference in student learning outcomes through the effectiveness of using Virtual Reality-Based virtual laboratories in the Internet of Things Course in the Electrical Engineering Study Program is significantly and significantly different. The results of the experimental class data analysis obtained the t_count > t table value, namely 8,351 > 2,003 and the Sig. (2-tailed) 0.005 <0.05, then Ha is accepted, meaning that there is a difference in the average student learning outcomes after using a virtual reality-based virtual laboratory in the internet of things course in the Electrical Engineering Study Program. Student motivation through the use of Virtual Reality-Based virtual laboratories in Internet of Things Courses in the Engineering Study Program can increase very well

Three-dimensional modeling is used as a new way of presenting information about the electromagnetic compatibility of telecommunications infrastructure equipment. We analyzed the problem of modeling of electromagnetic noise waves equipment and communication channels of telecommunications monitoring systems. Conducted the analysis of control problems of telecommunications equipment electromagnetic compatibility. Described the real conditions of installing the electronic equipment in computational complexes. Using tools of 3D-modeling was formed cable route, taking into account the suppression of noise waves, placement of telecommunication devices and checking whether the threshold value of cable susceptibility for all options of its gasket between devices was transcended. It is proposed to study the behavior of electromagnetic fields in the cable lines with shielding cable, electrostatic discharge, providing set of measures for electromagnetic compatibility, to convert created in a three-dimensional environment model in a specialized settlement package. The prospects of the use 4D-, 5D-, 6D-simulation for analysis of the implementation of projects, reduction of operating and electromagnetic compatibility costs.

On limited space of the same platform, more and more radio electronic equipment are increased, which results in more problems of electromagnetic compatibility(EMC) that almost all of them caused by antenna mutual-coupling. As the example of two radar on the same platform, this paper gives the EMC test data in each carrier frequency band. Through the test data analysis it can be concluded that the electromagnetic interference (EMI) caused by adjacent frequency channel interference, According to the results of spectrum measurement, when increasing the carrier frequency interval it can ensure the two radar works well compatibility.

The paper deals with solving electromagnetic compatibility (EMC) problems in the design of a new, case study, industrial high voltage test laboratory, intended to be used for testing of transformers and other apparatus up to 550 kV rated voltage. Modern high voltage test facilities are equipped, apart from primary test devices like AC, DC and impulse voltage generators etc., also with sophisticated numerical measuring instruments and informatics technology. Since such devices are sensitive to transient overvoltages, the highest degree of EMC is to be secured. This can be achieved by proper earthing and screening of test laboratory, what shall be designed in a way to satisfy all requirements conditioned by building lightning protection, personal protection and system earthing, avoiding electromagnetic compatibility disturbances at the same time. One of the main tasks is solving electromagnetic compatibility problems caused by outdoor electromagnetic disturbances originating from various unknown sources. Those disturbances and interferences may seriously influence measuring accuracy and readings of test devices, what consequently leads to false results. The stated is especially relating to partial discharge measurements. As to avoid such disturbances, the laboratory shall be completely screened with a net forming optimally designed Faraday cage. On the other hand, at high voltage tests with impulse voltages, especially with chopped tail waves, steep transient overvoltages may be generated. As a consequence, high transient potential differences between particular points along the earth electrode may occur, what can even lead to flashovers between parts of it. Therefore is of utmost importance to provide proper earthing and low inductance current return path for impulse high voltage test equipment where high frequency transients are to be anticipated. Improper earthing and bonding may result, apart from mentioned flashovers, in severe induced voltages in secondary cables with consequential influence on test results, possible destruction of measuring instruments and hazardous touch voltages for personnel. For analyzing transient potential differences, it is important to model, with maximum accuracy, impulse test circuit (impulse generator, chopping spark gap, voltage divider, Faraday cage, fundament earth electrode, earthing strips, earthing rods etc.). Magnitude of transient potential difference between particular points is proportional to earth electrode inductance, i.e. low inductance of earth electrode will result in decrease of transient potential difference.

The electron cyclotron resonance heating (ECRH) is a very important plasma heating method in experimental advanced superconducting tokamak (EAST). There are four gyrotrons in the EAST ECRH system that can generate 4-MW/100-s/0.14-THz wave. The ECRH system is a complex terahertz system that involves ultralow temperature, ultrahigh vacuum, strong magnetic field, high-power electromagnetic wave, and weak diagnostic signal. There are many electromagnetic compatibility problems in the ECRH system. This is the first report about the electromagnetic compatibility for the ECRH system. In the operation of the ECRH system, many electromagnetic compatibility problems have been found and resolved. We can suppress the interference and improve the accuracy of power monitoring and the effectiveness of radio frequency protection by using the magnetic rings. The influence of the magnetic field on the current transformers was analyzed. Some electromagnetic compatibility issues in the data acquisition system were discussed. After solving the electromagnetic compatibility problems, the EAST ECRH system can stably output high-power terahertz wave.

This paper deals with energy/power quality issues, correlated with Electromagnetic Compatibility (EMC) and electromagnetic interferences (EMI) which appear at urban transportation systems. One presents, briefly, some aspects regarding powers definitions for harmonic and/or unsymmetrical regimes from three-phase circuits, applicable to loads supplied from the a.c. line through low voltage power transformers and uncontrolled three-phase rectifiers. It is analysed the case of a driving system with d.c. motor and chopper, supplied from the d.c. line, which induces a significant non-sinusoidal regime in the a.c. network. The cases in which the load is not compensated, respectively compensated through an active filter are also analyzed through tests on stand. Aspects regarding powers and power flows for both cases are also discussed. Furthermore, the obtained data are compared using the quality standards IEEE 519/1992 and 1459/2000. One discusses the obeying of quality standards and some aspects, which are not approached in the specialty literature, concerning the corresponding EMC and EMI issues. Problems related to the tested driving system connection to the supplying system from the power substation for an urban transportation system are briefly presented. The waveforms of currents through the active filter are depicted. Some conclusions on approaching EMC and EMI at low frequencies, with an extension over 2 kHz and the relation with the IEC 61000-4-30 standard are also presented. It is underlined the necessity of treating energy/power quality issues in correlation with issues regarding EMC and EMI at low frequency for this type of loads.

The basic electromagnetic compatibility (EMC) problem is very simple to describe at a high level, as shown, where the elementary EMC problem breaks down into a source, a path and a victim. Ensuring EMC needs a good understanding of all three aspects. Sources can be further subdivided into continuous and transient sources and the pathway splits into radiated and conducted coupling. This paper primarily concentrates on the conducted aspects and in particular how we test to ensure equipment has adequate conducted EMC performance.

In response to the demand for cultivating high-quality applied professionals with both engineering and humanistic qualities in the new era, contemporary university education not only undertakes the responsibility of imparting professional knowledge and skills, but also shoulders the responsibility of ideological and political education for students. This article design the teaching process and evaluation system of Electrical Engineering courses in order to cultivate engineers with both moral integrity and professional competence.Through course learning, students will not only master the basic knowledge and corresponding skills of electrical and electronic technology, but also possess the spirit of striving for excellence as a national craftsman, with a sense of serving the country through science and technology.And the students will be able to undertake the mission of the great rejuvenation of the Chinese nation. By studying the teaching mode of electrical engineering courses, reference value is provided for the reform and innovation of higher education related majors and teaching curriculum systems

This paper presents a computationally efficient method for solving automotive low-frequency electromagnetic compatibility (EMC) problems by using integral equations. We consider the interaction of magnetic fields with thin, finite, conducting 3-D metallic structures, obtaining the fields radiated by these structures by using single- and double-layer equivalent currents. Our proposed numerical solution is unique in its representation of equivalent currents as the sum of solenoidal and nonsolenoidal components found using the method of moments (MoM) in two steps: first, the solenoidal currents are found using loop basis functions, after which the nonsolenoidal currents are found. Decomposing the equivalent currents into solenoidal and nonsolenoidal components provides a total solution that is computationally efficient for problems dominated by magnetic fields. We validated this numerical electromagnetic solution against semianalytical solutions and measured data and illustrated its applicability by analyzing three practical automotive problems. We then analyzed the magnetic fields generated by a power cable inside a car, suggested a methodology for optimizing the locations of antennas for smart-entry systems, and studied the EMC implications of an inductive-charging system in an electric vehicle.

This paper investigates electromagnetic compatibility (EMC) problems in artificial intelligence (AI) products and summarize corresponding solutions. Concept and theories of EMC are introduced in Section II, analysis of EMC problems in AI products basing on three elements of EMC is given in Section III, solutions are presented in Section IV, and conclusions are given in the final Section.