2017/2018

2018/2019

DM270

DEPARTMENT OF ELECTRICAL,COMPUTER AND BIOMEDICAL ENGINEERING

ELECTRICAL ENGINEERING

Energetica

2°

Annual (01/10/2018 - 14/06/2019)

12

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

The course is made up of two different modules; the first one (9cfu) is partially borrowed from Industrial Drives for Industry Applications , while the second one (3 cfu) concerns the efficiency of air compressed systems.

Electrical Drives for Industrial Applications (9 cfu)-
reviews the basic concepts concerning 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.

Energy Efficiency in Compressed Air Systems (3 cfu) -

This course is attended by the 2nd year students of the Laurea Magistrale degree in Ingegneria Elettrica. curriculum Energetica.

In the following are resumed for each of the two modules the main topics of the course.

Electrical Drives for Industrial Applications (9cfu, please note that the list of the arguments is not in cronological order).

Dynamic Mechanical equation: reflected torque and inertias, torque/speed load and actuators curves, stability of an operating point, jerk, optimal transmission ratio, motor-load elastic coupling, constant torque/power operating regions.

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, reconstruction of flux and torque variables, field weakening operation.


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; compensation of dq coupling terms.

Space Vector PWM and 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 hysteresis regulators, voltage saturation, decoupled current control.

Electrical Drives with dc machines fed from SCR rectifiers and choppers; voltage and current waveforms, continuous and discontinuous operation, transfer functions, steady-state and dynamic
behavior.
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.

Energy Efficiency in Compressed Air Systems (3cfu) -

Electrical Drives for Industrial Applications
Lectures (9cfu)(hours/year in lecture theatre): 52
Practical class (hours/year in lecture theatre): 28
Practicals / Workshops /Seminars (hours/year in lecture theatre): 4


Energy Efficiency in Compressed Air Systems (3cfu) -

Electrical Drives for Industrial Applications (9cfu)-
In the following a list of taxtbooks related to ED is presented. Additional material (notes, links, papers and so on) will be given during lectures. Please refer to KIRO Portal.


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

W. Leonhard. Control of Electrical Drives. Springer Verlag, 1998.

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.


Energy Efficiency in Compressed Air Systems (3cfu) -

The preparation is verified separately for the two modules; the final grade of the exam is given by a weighted average.

Electrical Drives for Industrial Applications (9cfu)-
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 report on specific topics could be required; the interest displayed during the lectures can contribute to the evaluation.


Energy Efficiency in Compressed Air Systems (3cfu) -