


Politecnico di Torino  
Academic Year 2015/16  
01NMMNC Computer aided design of electromagnetic devices 

Master of sciencelevel of the Bologna process in Electrical Engineering  Torino 





Subject fundamentals
The course aims at introducing the student to the main numerical analysis methods and tools commonly used in electrical engineering. Firstly, the theoretical bases of the methods used are outlined and then several problems coming from the application fields are analysed and solved. Laboratory exercises will be performed using computational procedures actually used in electrical engineering design activity.

Expected learning outcomes
At the end of the course students will have the ability to analyse an electromagnetic problem with standard characteristics and define which is the most proper numerical tool to be used, analyse it by means of it and then evaluate in a critical way the obtained results.

Prerequisites / Assumed knowledge
Most of the concepts used in numerical analysis will be introduced throughout the course, anyway the basic knowledge about electromagnetic fields and about their working regimes are given as already known.

Contents
Introduction to electromagnetic problems and their ranking in terms of difficulty, lumped parameters models, one  two  three dimensional problems, subdivision of the analysis process in subphases (discretization, solution, postprocessing of results). (4 hours)
Introduction to numerical methods for the discretization of the continuous problem and its computer aided solution: outline of variational methods (finite element method), algebraic methods (cell method), integral methods and hybrid methods. Introduction of the main commercial codes that will be used in the informatics laboratory (Matlab, FEMM, CST etc.). (16 hours) Onedimensional problems: multiconductor transmission lines, analysis of faults, direct lightning, nonlinear phenomena (surge protection devices, flashover, ground ionization), solution examples. (8 hours) Electrostatic field analysis, capacitance computation in twodimensional problems, comparison with image method, sharp tips in threedimensional problems. (4 hours) Current field analysis, ground resistance computation, interaction between ground condutors, outline of ground ionization phenomenon. (6 hours) Magnetostatic analysis, inductance computation, magnetic circuits with currents and permanent magnets, evaluation of threedimensional effects on dispersed inductance, nonlinearity and saturation, force computation, use of ferromagnetic materials in magnetic shielding. (8 hours) Magneto quasistatic field analysis: eddy currents, losses, outline of induction heating, use of conductive mateirals in magnetic field shielding. (10 hours) Multiphysics problems: electromagnetic and thermal coupling, electromagnetic and elastostatic coupling. (4 hours) 
Delivery modes
In addition to lectures, the students will take part in five informatics laboratory exercises about the topics taught in classroom:
Onedimensional problems: study of a power transmission line under a lightning direct hit; Electrostatic analysis: capacitance computation in complex geometrical structures, capacitive divider; Current field analysis: ground resistance evaluation; Magnetostatic analysis: nonlinearity effects on a magnetic circuit of an electrical machine and evaluation of threedimensional effects; Magneto quasistatic analysis: eddy currents in ferromagnetic materials, shielding by means of conductive materials. 
Texts, readings, handouts and other learning resources
Material relevant to the course (slides) will be available to students through the course web site.
Reference books  Silvester P.P., Ferrari R.L. "Finite elements for electrical engineers" Cambridge University press, 1996  Lowther, D.A., Silvester P.P. "Computer aided design in magnetics" Springer Verlag, copyr. 1986  Zienkiewicz, O.C., Taylor, R.L. "The finite element method for solid and structural mechanics" Elsevier, 2005  Tonti E., Nuzzo E. "Gradiente, rotore, divergenza" Pitagora, 2007  Tonti, E., "The Mathematical Structure of Classical and Relativistic Physics, A General Classification Diagram", Springer Series: Modeling and Simulation in Science, Engineering and Technology (2013)  P. Alotto, F. Freschi, M. Repetto C. Rosso, "The Cell Method for Electrical Engineering and Multiphysics Problems: An Introduction"  Springerverlag Berlin And Heidelberg Gmbh & Co.  January 2013 
Assessment and grading criteria
Passing the exam involves:
• Preparation of a report for each of the five practical exercises assigned during the course. The activity at the computer will be performed by groups and each group will have to carry out a different task. The report will be prepared jointly by the group. The evaluation of the result produced will be collective and will be made after a oral discussion (max 20/30). • Report on a research topic, developed starting from a scientific paper of broad content proposed by the teacher, and orally discussed. The scoring of this part will be individual (max 10/30). 
