OVERVIEW

The course is poposed at the 1st cycle of the 1st year of the Master Degree in Electrical Engineering. Contents are placed in the framework of the electromechanic energy conversion, fundamental topic of the curriculum in Electrical Engineering for power system analysis and energy conversion modeling and control.

AIMS AND CONTENT

LEARNING OUTCOMES

The course proposed a dynamic modelling oriented approach of electrical machines for transient, dynamic and harmonic application studies. Suitable analytical and numerical tools are provided to face with analisys and control problems and defined proper proteciton systems.

LEARNING OUTCOMES (FURTHER INFO)

Aims previously focused are related to analysis and management of production, conversion and utilization of electric energy systems, fundamental topics in Electrical Engineering. Dynamic modelling of electric machines together with analytical and numerical tools are provided in order to face with control, protection and harmonic problems in power system, drives and industrial network including renewable electric energy sources.

TEACHING METHODS

Teaching approach

Course couples theoretical lessons (about 50 hours) with practical applications including model set-up and numerical computations, sometime using computer aided dynamic simulation programs. Exercises concern with solution of simple problems on course content involving student partecipation.

SYLLABUS/CONTENT

Summary

Course contents concern transient and dynamic modelling of electric machines. Transformer saturated models are derived and used for investigating inrush current, ferroresonance, short circuit and overvoltages phenomena. Modelling of rotating machines are developed based on the generalized theory of electromechanic energy conversion according to the coupled circuit in relative motion approach and related reference frame transformations.

Contents

1. Transient phenomena in electric machines. Time-frame classification. Analysis approaches.

2. Transformers. Non-linear transient model including saturation effects. No-load current waveform distortion. In-rush and short circuit currents. Ferroresonance. Overvoltages distribution and dielectric strength.

3. Electromechanic energy conversion. Coupled circuit theory of electromechanic systems. Energy balance. Electromagnetic forces and torques from magnetic energy and co-energy. Permanent magnet systems. Step motor applications

4. Studio di transitori elettrici e/o elettromeccanici significativi nell'esercizio delle macchine elettriche rotanti.

4. Introduction to modelling and dynamic of rotating electric machines. Coupled circuit description of DC, induction and synchronous machines. Dynamic equations. Reference frame transformation. Dynamic equivalent circuits. State space equations. Reduced order models for special purpose applications. Operational and vector approaches. Block diagrams. Dynamic model initialization from steady-state analysis. Parameter identification.  Modelling application to the study of relevent dynamic behaviour in management and control of rotating electric machines (DC motor start-up, AC supply of series-excited DC motor, induction motor short circuit, direct on line and variable frequency induction motor start-up, induction motor flux oriented control, syncronous machine short circuit, synchronous machine transient stability).

RECOMMENDED READING/BIBLIOGRAPHY

Recommended Reading

Course lecture notes are collected and made available on the web site of the University of Genova.Furthermore, some references dealing with course content are given. Students are non required using them to prepare examination but only to improve their ability level.

References

1. Fitzgerald, Kingsley, Kusko - Electric Machinery, The Processes, Devices and Systems of Electromechanical Energy Conservation, 3rd Edition, Mc Graw Hill.

2. Krause, Wasynczuk, Sudhoff - Analysis of Electric Machinery and Drive Systems, 2nd Edition, Mc Graw Hill.

TEACHERS AND EXAM BOARD

Exam Board

GIO BATTISTA DENEGRI (President)

MARCO INVERNIZZI

RENATO PROCOPIO

LESSONS

LESSONS START

Course is offered in the first cycle (September - December) Of the academic year.

Lesson scheduling is available on the web site of the Politechnique School of the Univerisy of Genova.

Class schedule

DYNAMICS OF ELECTRICAL MACHINES

EXAMS

EXAM DESCRIPTION

Examination approach

Check of student preparation level is performed by an oral test aiming to put into evidence both the knowledge of corse content and the ability to apply modelling methodologies.

Exam schedule