2016/2017

2017/2018

DM270

ING-IND/32 (POWER ELECTRONIC CONVERTERS, ELECTRICAL MACHINES AND DRIVES)

DEPARTMENT OF ELECTRICAL,COMPUTER AND BIOMEDICAL ENGINEERING

ELECTRICAL ENGINEERING

Energetica

2°

Annual (02/10/2017 - 15/06/2018)

6

45 lesson hours

Italian

WRITTEN AND ORAL TEST

BASSI EZIO (titolare) - 3 ECTS
ANGLANI NORMA - 3 ECTS

Principles of electrical engineering and mechanics, analysis of periodic waveforms, vector diagrams, basic elements of electrical machines and power electronics.

The course outlines in its first half the basic concepts about functional characteristics, design and applications of electrical variable speed drives at steady state, with a few hints on their control and transient behavior. In the second part are addressed items concerning the dynamical behavior of electrical drives: various regulation schemes are introduced, principally with induction and brushless motors, with different solutions as to the controlled variables and the regulation algorithms.

The students of the percorso energetico are required to attend the first 9 cfu of the course titled "Azionamenti Elettrici Industriali-Electrical Drives for Industry Applications" (12 cfu, E. Bassi). Of these 12 cfu, the first 6 ones define one half (module A) of "Azionamenti Elettrici per Energetici", while the second half (module B) is made up of 3 further cfu taken from the 12 cfu course (Bassi) plus 3 cfu having a strictly energy management content (N. Anglani).
In the following are then resumed a few topics of the 12 cfu course.

Inverter-fed Induction machine
Dynamic model of the IM and instantaneous torque; different reference system and transformation matrices; vector representation of three-phase variables; Field Oriented Control: direct and indirect implementaion, reconstrauction of flux and torque variables, field weakening operation. Energy saving with use of Variable Speed Drives (VSD).

A.C. current control
Control of the currents of a three-phase system (i.e. motor) in different reference systems (abc, αβ, dq); PI regulators; Hysteresis regulators; predictive control; compensation of dq coupling terms.

Space Vector PWMand a.c. current control
Inverter configurations, voltage reference and basic principles of the method, limit voltage exagon and overmodulation, optimal sequence of inverter states, switching frequency and current ripple; effect of dead-times and common mode voltage.
Open- and closed-loop control; current control on different reference frames with linear (PI) and hystereisi regulators, voltage saturation, decoupled current control.

Brushless Drives
Use of Permanent magnets, different types of rotor design and rotor saliency, elctromagnetic force induced on the stator windings (d.c. and a.c. BL), effect of saliency on torque; cogging; regulation schemes; steady-state operation and geometrical loci in the field-weakening region.

Lectures (hours/year in lecture theatre): 30
Practical class (hours/year in lecture theatre): 25
Practicals / Workshops /Seminars (hours/year in lecture theatre): 4

Legnani, Tiboni, Adamini. Meccanica degli Azionamenti vol. 1 - Azionamenti Elettrici. Progetto Leonardo, Bologna, 2002.

w. Control of Electrical Drives. s.

Bimal K. Bose. Power Electronics and Variable Frequency Drives. Technology and Applications. IEEE Press, 1997.

Mohan, Undeland, Robbins. Elettronica di potenza. Convertitori e applicazioni. Hoepli, Milano, 2005.

Murphy, Turnbull. A.C. current control. Pergamon Press,1988.

L. Bonometti. Convertitori di potenza e servomotori brushless. UTET 2001.

Oral exam during which the students can be required to solve a simple written exercise on the very basic contents of the course. A written relation on specific subjects and the interest displayed during the lectures can also contribute to the evaluation