PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING
Learning outcomes of the course unit
The course aims at providing basic knowledge and methods for the analysis and synthesis of linear circuits in DC, AC and transient conditions. Part of the contents will be preparatory for later Electronics courses.
For goals related to learning how to teach electric science and technology-related subjects see Annex B of Italian D.M. 616.
Students must be familiar with the concepts and methods treated during the first year of the course (Mathematical analysis, Analytical geometry, Physics).
Course contents summary
Analysis and synthesis on linear electric circuits in direct current, alternating current, and transient operation. Energy analysis. Frequency analysis.
The course complies with Italian D.M. 616, August 10, 2017.
1) Steady-state electrodynamics (4 hours).
Voltage and currents. Resistor, voltage and current independent generators, Ohm's laws, energy. Voltage and current limits, rated values. Thermal sizing.
2) Direct current circuits analysis and synthesis (12 hours).
Connections among bipoles. Kirchhoff's principles. Mesh analysis, node analysis, delta/wye transformations, superposition principle, Millman's theorem. Thevenin's theorem, Norton's theorem. Measurement instruments. Dependent generators.
3) Steady-state electric fields (4 hours).
Electric filed, capacitance, capacitor, constitutive law of the capacitor. Dielectrics and electrical insulation. Parasitic capacitances. Energy behaviour. Charge and discharge.
4) Quasi-stationary electromagnetic field (5 hours).
Magnetic field, diamagnetic, paramagnetic and ferromagnetic materials, loss figure. Faraday-Lenz's law. Inductor, constitutive law of an inductor, energy behaviour. Magnetic circuits. Charge and discharge. Stray inductances. Lumped parameters circuits. Connections among reactive components.
5) Electric circuits in transient conditions (5 hours).
Analysis of first and second order electric transients in the time domain. State variables.
6) Electric circuits with sinusoidal supply (10 hours)
Symbolic method (Steinmetz's transform). Active and reactive power, power factor, Boucherot's theorem. Power factor correction. Introduction to polyphase systems and electric energy transmission. Maximum power transfer theorem.
7) Frequency domain electric circuit analysis (11 hours).
Frequency response of electric circuits. Transfer functions and Bode diagrams. Filters. Series and parallel resonance.
8) Two-port electric networks. (4 hours).
Representation of two-port electric networks with impedance matrix, admittance matrix, hybrid parameters, and transmission matrices. Connections among two-port networks.
9) Coupled inductors and transformers (4 hours).
Mutual inductance, ideal and real transformers, constitutive laws, applications of transformers, open and short circuit tests, autotransformers.
C. K. Alexander, M. N. O. Sadiku, ”Circuiti elettrici”, 4a ed., McGraw-Hill.
A. Canova, G. Gruosso, M. Repetto, "Elettrotecnica-Esercizi svolti", Esculapio-Progetto Leonardo.
Johnson David W., Johnson Roger T., Holubec Edithe J., Apprendimento cooperativo in classe. Migliorare il clima emotivo e il rendimento, Erickson, Trento, 1996.
Jonassen David, Howland Jane, Marra Rose, Crismond David, Meaningful Learning with technology, Pearson Education, Upper Saddle River – New Jersey – Columbus – Ohio, 2008.
Classroom lectures and exercises solved by the instructor.
Assessment methods and criteria
1. Written exam with 3-4 problems and 1-2 theoretical questions. During the exam the student will have to demonstrate knowledge of circuit analysis and synthesis techniques in direct current, alternating current and transient operation, frequency analysis, energy analysis.
2. Optional oral exam for those students who successfully pass the written exam, mandatory for those who are one or two points below 18/30. The oral exam, successfully passed, can increase the written exam mark by up to 5/30. A bad performance can lower the mark indefinitely.