educati.on an relaeea rob e s at a llinn

Technical Universty

Jaan Jarvik, Kuno Janson, Viktor Bolgov, Peep Kroos

Abstract - Taking into account the importance ofelectromagnetic compatibility (EMC), modern electricaleducation requires more attention to give future electric andelectronic engineers with good EMC knowledge. Thepurpose of this paper is to present the current situation withEMC educational and lab activities, as well as plans for thefuture at Tallinn University of Technology, Estonia. Thepaper describes the existing course and contents of creatingcourses in EMC given in the Department of ElectricMachines and Fundamentals of Electrical Engineering. Theaim and proposed effect of the courses are outlined.

Index Terms - educational courses, electrical engineeringeducation, electromagnetic compatibility, electromagneticinterference, training

I. INTRODUCTION

Electrical and electronic products are related to everyaspect of modem life. However, they also createnumerous problems such as EMI and others requiringmore and more attention to electromagnetic compatibility(EMC). There are not so much trained engineers in thisfield in Estonia. This subject was taught at bachelors'level at the Faculty of Power Engineering of TallinnUniversity of Technology (TUT), but the change fromfour-year to three-year undergraduate education programforced to shift the EMC learning to master's and doctorallevels. The elaboration ofnew programs was started.To ensure that future engineers would have a deeper

understanding of the subject, some space has to be foundin already overloaded programs. Efforts are being made tohelp students understand the importance of consideringEMC. It could also be possible to give some basicknowledge of EMC in secondary schools in Estonia. Theinternational relationship for developing the EMCeducation is organized by financial help ofEU.

This work is supported by the Foundation for Lifelong LearningDevelopment "Innove" under Grant 1.0101-02790.

Jaan Jarvik is with the Department of Electric Machines andFundamentals of Electrical Engineering, Tallinn University ofTechnology (TUT), Tallinn, 19086 Estonia (phone: 372-620-3800; fax:372-620-3800; e-mail: jaanvikAcc.ttu.ee).

Kuno Janson is with the Department of Electric Machines andFundamentals of Electrical Engineering, TUT, Tallinn, 19086 Estonia(e-mail: kunojansonAstaffttu.ee).

Viktor Bolgov is with the Department of Electric Machines andFundamentals of Electrical Engineering, TUT, Tallinn, 19086 Estonia(e-mail: victor bolgovAyahoo.com).

Peep Kroos is with the Department of Electric Machines andFundamentals of Electrical Engineering, TUT, Tallinn, 19086 Estonia(e-mail: p.kroosAttu.ee).

The paper describes the existing course and contents ofdeveloping courses in EMC at the Department of ElectricMachines and Fundamentals of Electrical Engineering.The aim and proposed effect of the courses are outlined.The EMC program has been splitted into two parts. Thefirst part is EMC education during the master's studies.The second one is advanced education for PhD students.The courses include a comprehensive introduction toEMC nature and problems, analysis techniques,computational methods, EMI measurement, as well asvarious standards and specifications used internationally.

II. PRESENT SITUATION

There is only one university providing highereducation in field of technology in Estonia - TallinnUniversity of Technology. Most of courses are held inEstonian. New learning courses have sometimes to beelaborated to keep up to date with modern science andtechnology. That is why a new relevant course"Electromagnetic compatibility" was elaborated at theDepartment of Electric Machines and Fundamentals ofElectrical Engineering and proposed for learning at theDepartment of Electrical Drives and Power Electronics inApril of 1995. The course was indented for four-yearbachelor's degree level. EMC related courses were alsostarted at the Radio and Communication Department ofthe Faculty of Information Technology in 1997.

The experience in power quality obtained fromresearch works over long period of time facilitated theelaboration of the EMC course at the Department ofElectric Machines and Fundamentals of ElectricalEngineering. Another advantage was taken of apreviously created Estonian EMC lexicon. It was madeby translation different parts of IEC EMC standards intoEstonian. According to EEC Directive, all basic EuropeanEMC directives and standards were accepted as Estonianstandards.An obstacle encountered during the course elaboration

was a fact that EMC courses were taught in few technicaluniversities in 1995. Proper textbooks for students werelacking. The most of foreign EMC textbooks wereproposed for practicing engineers. The problem was alsoin small interest towards a field theory learning andteaching, because digital electronics became the mostpopular subject. The learning of the EMC course requiresgood competence in Fundamentals of ElectricalEngineering, because a large number of theoreticalquestions cannot be considered due to lack of time. A lotof questions are presented formally by means ofmathematics and basic electrical relationships, which areof great importance in EMC education, are not clear tostudents.The textbooks in Electrical Engineering contain too

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many mathematical expressions and are over-sized. Asmall textbook with a short overview of fundamentalphysics behind electrical values and their interrelations ismissing. That is why operational principles of manysimple elements and devices, for example transformers,are not often obvious. Some aspects of these questionswere included in the taught EMC course [1].

The bachelor's course content is as follows:Introduction to EMCDescription ofEMI problems natureEMI main sourcesDisturbances due to equipment operation and switchingtransientsDisturbances in power electronicsShieldingGroundingReliability at pulse disturbances

This core course gives 2.5 credits and involves 48academic hours. There are 32 lecture hours and 16exercise hours. The course was taught in Estonian.

After starting 3+2 learning curriculum, the need fornew courses at higher level was encountered. The lack oftime, as well as other mentioned before problems becamemore drastic. The EMC course is now taught at masterand doctoral levels. The elaboration of these new courseswas started with financial support in frame of EUprogram for development of lifelong education.Two textbooks, laboratory works and proper learning

aids elaborating within an international program (Estonia,Russia, and Germany) are supposed to solve the problem.The master level textbook is a fundamental part. Thedoctor level textbook describes special issues with aspecial emphasis on power electronics, electronics,electrical power engineering. The problems related totelecommunication and informatics are only outlined.Content and structure of the courses are consideredbelow.

III. MASTER'S COURSEThe purpose of an EMC course in the master education

is to make the students aware of the existence ofEMC, itsnature and main problems.

The first textbook describes the fundamentals of EMC.It is dedicated to the common EMC problems related toelectrical and electronic equipment, including translationand use of basic definitions and terms. Efforts are aimedto help students to understand the importance ofconsidering EMC in design and use of electrical andelectronic units and systems. The structure is as follows:Main emission sources. Natural interference sources,disturbances due to switching transients and nuclearexplosion.Disturbances in power electronicsDisturbances in electrical power systemsUse of circuit theory and interference couplingmechanismsDisturbances distribution and impact on electronic andelectrical equipmentDisturbance suppression. Passive disturbance suppressionunits. Electromagnetic shielding. EMI protection andimmunity improving for equipment

Certification and standards in EMC field for electronicand electrical equipmentEquipment immunity testMeasuring disturbances parameters. Laboratory immunitytestDesigning electronic units according to EMCrequirementsEMC standardization. EMC in Internet

Guest professors are going to be invited from Saint-Petersburg State Polytechnic University, Saint PetersburgElectrotechnical University and State Marine TechnicalUniversity of Saint-Petersburg to give some lectures.These lectures will include both topics chosen forpresentation and EMC real case stories. Such apresentation of the material is valuable for the studentsdue to understanding how the EMC subject is related tothe "reality" they could meet in their engineeringpractice.

This elective course gives 2.5 credits and involves 48academic hours. There are 36 lecture hours and 16exercise hours. The course is held in Estonian. Somebooks [1]-[5] were used to develop the course.

IV. ADVANCED COURSEThe second textbook includes both theoretical

fundamentals on an advanced level and more detailedpractical implementations. The course includesfundamental parts from circuits, signal and systemtheories, theory of electromagnetic fields, electronics aswell as others. Different symbolic and numericalcalculation techniques are considered. Big attention ispaid to electronics, as these devices continue to beincreasingly produced and the need for effective EMCdesign has become more critical to meet international andgovernmental regulations. It is explained how to use thebasic principles to design electronic systems in such away that they satisfy standards and perform reliability inthe presence of interference source.

The table of content of the second textbook ispresented below:Chapter 1. EMC theoretical fundamentalsBasics of decomposing designElectromagnetic topology of object and EMC designingCalculation methods and their application to EMC tasksCalculation methods accuracyEMC reverse tasksModeling devices with lumped parameters in EMCexercisesSubstituting circuits for modelingEquipment modeling in frequency and time domainswithout substituting circuitsSubstituting circuit synthesize according to test dataMeasuring frequency response; S-parametersSynthesizing substitution circuits in frequency and timedomainsModeling devices with distributed parameters in EMCexercisesLong lines theoryModeling distribution systems in frequency domainModeling disturbances in cable lines

Impact of electromagnetic fields on cable linesTransient impedance of cable lines and its measurementTheoretical fundamentals of cable lines transientimpedanceShieldingShielding mechanisms

Chapter 2. EMC in electric plants and substationsEmission sourcesMagnetic and electric fields calculationImpact of over voltage waves on transformersCalculation of induced voltages in low-voltage networksand equipmentHigh-speed transients in low voltage networksEMC protection of communication and control linesEMC protection of low voltage equipment, grounding,shielding, dischargers etc.

Chapter 3. EMC in radio engineeringIntroduction to EMC problems in radio engineeringEMC of radio electronics and problem sourcesEMC analyzing methods for radio electronicsElectromagnetic waves propagation in free spaceAntennasRadio receiversEmission of radio transmitters, EMCImpact of radio receiver and transmitter on EMCEMC assessment criterionProtecting radio equipment and communications fromdangerous EMIEMC reliability methods in radio engineeringTypes of disturbances and coupling waysDisturbances suppression methods

The first laboratory exercise allows comparing ashielding effect of ferromagnetic and non-ferromagneticmetals. The shielding containers are of spherical andcylindrical forms with different wall thicknesses. Theregulating AC magnetic field is to be measured by sensorinside a container.The second experiment is to model grounding effect at

different grounding conditions. The third one showsimpact of EMI on electronic units with and withoutprotection measures.

VI. CONCLUSIONThe staff of our department is trying to improve the

situation with teaching EMC to electrical engineeringstudents. These efforts are aimed at creation of the newEMC courses at master's and doctoral levels.

REFERENCES[1] J. Jarvik, Electromagnetic Compatibility (in Estonian).

Tallinn: TUT, 2006.[2] A. Worshevsky, Fundamentals of Electomagnetic

Compatibility (in Russian). Tallinn: TUT, 2007.[3] A. Djakov, Electromagnetic Compatibility in Electrical

Power Engineering and Electrical Engineering (in Russian).Moscow: Energoatomizdat, 2003.

[4] A. Schwab, Electromagnetic Compatibility (in Russian).Moscow: Energoatomizdat, 1998.

[5] Tim Williams, EvC for Product Designers. Oxford:Newnes, 2001.

Chapter 4. EMC for electrical designs. Layout andgroundingProtecting electronic units from electrostatic dischargeDigital and analogue circuit designInterfaces, filtering and shieldingEMC reliability methods

This elective course will give 4 credits and involve 48academic hours. There are 36 lecture hours and 16exercise hours. The course language is Estonian.

V. LABORATORY EXERCISESIt is important that the students would have an

opportunity to conduct experiments. These will help thestudents to understand the course material, give them anopportunity to use measurement equipment and providethem with realistic numerical data that could be observedin practical cases.At present there are no laboratory classes included in

the course at the master's level, but they are elaborating.The laboratory works is supposed to include 8 experimentseries, each one of 2-hour duration. For example, 3 labsare being developed currently - electromagneticshielding, grounding, EMI impact on electronic units.