28633 - Electrotechnics T-A (A-K)

Learning outcomes

Expand and develope of concepts and methodologies relating steady state and quasi steady state electromagnetism. Provide the main tools for the analysis of electric and magnetic circuits. Illustration of the construction and operation of the main electrical machinery and components of an electric power system.

Course contents

Electromagnetic Fields
Recalls on the main vector operators. Basic definitions. Maxwell's equations in differential and integral form. From field theory to the theory of circuits.

Electrostatics
Laplace and Poisson equations, the general problem of electrostatics, capacitors

Electric Circuits
Lumped circuits and networks. Read Kirkhhoff. Main circuit elements: resistors, inductors, capacitors, independent voltage and current. Steady state. Series and parallel of resistors. Transformations delta - wye. Methods of study of electrical circuits. Kirkohhoff method of equations. Method of node potentials. Mesh method. Superposition. Tellegen's theorem. Thevenin and Norton's theorems. Studies on transients in RC, LC, RLC circuits. Initial state of the components. Sinusoidal steady state. Symbolic Kirkhhoff laws. The concept of impedance. Analysis of circuits in sinusoidal regime using the symbolic method. Power in sinusoidal regime. Power factor. Three phase systems. Wye and delta loads. Balanced and unbalanced Loads. Power absorbed by a three-phase load. Three phase with neutral.

Magnetostatics
Magnetic properties of materials. Diamagnetic, paramagnetic and ferromagnetic materials. magnetic circuits. Self and mutual inductance coefficients

Principles of electromechanical energy conversion
Energy balances in electromechanical systems. Calculation of forces and torques in mechanical systems.

Electrical machinery
General. Magnetic circuits. Hopkinson's law. Loss phenomena in electrical machines.

The transformer. Operational principle. Field hypothesis. Internal and external equations. Equivalent circuits. No-load and short circuit conditions. Efficiency measurement .

Rotating magnetic field
Asynchronous machines. Operational principle. Field hypothesis. Internal and external equations. Equivalence theorem. Mechanical and electromechanical curves.

Synchronous machines. Operational principle. Internal and external equations.

Electrical systems. General information on electrical systems and their constitution. Power plants and energy sources, power lines, switchgear and protective devices, basic electrical safety grounding system

Readings/Bibliography

G. Rizzoni, 'Principles and applications of Electrical Engineering', Mc Graw Hill

C. Alexander, M. Sadiku, 'Electrical circuits', Mc Graw Hill

P. Ghigi, M. Martelli, F. Mastri 'Esercizi di Elettrotecnica', Ed. Pitagora

Teaching methods

Lectures, during which the teacher presents the topics on the agenda. Examples, applications and exercises done in class. Ascolta Trascrizione fonetica   Dizionario - Visualizza dizionario dettagliato

Assessment methods

Comprehensive examination: The comprehensive examination consists of a written test and an oral exam. The written test consists of two exercises. A score greater than or equal to 14/30 on the written test is needed to acces the oral exam.

Teaching tools

Handouts, information and other course material is distributed through a web site: http://campus.unibo.it/

Links to further information

http://www.die.ing.unibo.it/pers/cristofo/andrea.htm

Office hours

See the website of Andrea Cristofolini