Learning objectives
MODULE I
The course provides the basic knowledge required for the usage of the most common electrical machine and electric drives.
MODULE II
1) Knowledge and understanding
This module aims at providing students with basic knowledge and understanding of:
- sensors and transducers for electro-mechanical systems and applications
- circuits based on operational amplifiers for analog signal processing
- simple combinatory and sequential digital circuits
- basic principles and methods for analog and digital automatic control
- power electronic converters
2) Applying knowledge and understanding
Students will be made able to:
- choose the most suitable sensors and transducers for a specific application based on their characteristics and the specifications of the problem
- analyze the behavior of simple circuits based on operational amplifiers
- analyze and design simple analog automatic control loops
- synthesize combinatory logic circuits
- analyze the behavior of the most important electronic power converters and evaluate their performance based on the voltage and current waveforms
Prerequisites
The students are expected to be familiar with the notions of mathematics, physics, electrical and electronic circuits taught in the 1st level degree in Mechanical Engineering.
Course unit content
MODULE I
a) An Introduction to Electric machines
b) Transformers
c) Rotating machines
d) Electric Drives
MODULE II
1. Basic of semiconductor devices and solid-state power switches
2. Static energy conversion
3. Sensors and transducers
4. Signal conditioning
5. Digital signals
6. Closed-loop controls
Full programme
MODULE I
a) An Introduction to Electric machines
Electric machines classification. The main components of the electric
machines.
Joule losses and iron losses: the efficiency of the electrical machines.
b) Transformers
Ideal transformer and real transformer.
No load operations and rated load operations.
Voltage drop, power, losses and efficiency of electrical transformer. Three phases transformers.
c) Rotating machines
Induction machines: mechanical and electrical behaviour. Induction motor start-up and velocity regulation.
Direct Current machines: electrical and mechanical behaviour, start-up and velocity regulation.
Permanet Magnet Synchronous Machines (PMSM): a.c. and d.c. PMSM, electrical and mechanical behaviour.
Permanet magnet step motor, reluctance step motor and hybrid step motor.
Electric Drives classification.
d) Electric Drives
The main components of electric drives: speed and position transducers, current transducers. Analog and digital PID regulators, PLC.
Electric drives based on permanent dc motors: torque control and velocity control.
DC motor supply: soft switching chopper.
Electric drives based on PMSM: torque control and velocity control. Electric drives based on induction motors: torque and speed control. Incremental electrical drives: basic stepping motor control circuits.
MODULE II
1. Basic of semiconductor devices and solid-state power switches - 4 hrs
Pn diode. Npn bipolar junction transistor. N- and P-channel MOSFET. IGBT.
2. Static energy conversion - 16 hrs
Introduction and power converter figures of merit. Single-phase half-wave rectifier; battery charger. Single-phase full-wave rectifier with center-tapped transformer. Single-phase full-wave bridge rectifier. Low-pass filters. Single-phase full-wave bridge rectifier with RLE load. Three-phase full-wave bridge rectifier. Switching DC/DC converters: Buck; Boost; Buck-Boost; H-bridge; PWM modulation. DC/AC converters (inverters): single-phase half-bridge inverter; single-phase full-bridge inverter; three-phase full-bridge inverter. Full-bridge inverter modulation: single-pulse PWM, multiple-pulse PWM, sinusoidal PWM; space vector modulation.
3. Sensors and transducers - 6 hrs
Terminology. Displacement, position and proximity:potentiometer; capacitive sensors; inductive sensors; optical encoder; proximity switches; Hall-effect sensors. Velocity and motion: tachogenerator; AC generator; pyroelectric sensors. Force and pressure: load cells; piezoelectric sensors. Temperature: bimetallic stripes; RTD; thermistor; thermodiode and thermotransistor; thermocouples. Optical sensors: photodiode and phototransistor; photoresistor; CCD.
4. Signal conditioning - 16 hrs
Amplifiers and network functions. Differential amplifiers. Operational amplifiers: frequency behavior. Examples of application of operational amplifiers. 741 amplifier. Instrumentation amplifier: INA114. Logarithmic amplifier. Comparator. Protection and isolation circuits. Passive and active filters. Wheatstone bridge. A/D conversion: sampling and Shannon theorem. D/A converters: weighted resistor DAC; ladder DAC; ZN558D. A/D converters: successive approximations ADC; ZN439; flash converters. Sample & hold amplifier. Multiplexer. Data acquisition boards.
5. Digital signals - 4 hrs
Combinatory logic and logic operators; laws of De Morgan. Karnaugh maps; parity generator; comparator; decoder. Sequential logic: asynchronous and synchronous SR flip-flops; D and T flip-flops; JK flip-flop; registers; timer 555.
6. Basics of digital control - 2 hrs
Digital control. Adaptive control.
Bibliography
MODULE I
E.Bassi, A.Bossi “Macchine e Azionamenti Elettrici” UTET, Milano ISBN: 88-7933-184-1
Lecture notes
MODULE II
Topics 3, 4, 5, 6:
W. Bolton, "Mechatronics - electronic control systems in mechanical and electrical engineering", 4th ed., Pearson Educational, ISBN 978-0-13-240763-2.
Topics: 1, 2:
M. Rashid, "Power electronics", 3rd ed., Prentice-Hall, ISBN 0-13-122815-3.
Topics 1, 4:
R. Menozzi: "Appunti di elettronica", 2a edizione, Pitagora Ed., ISBN 88-371-1624-1.
Teaching methods
Classroom lectures and exercises solved by the instructor and by students. Some lectures use slides available to students for downloading.
Assessment methods and criteria
Oral exam. There is a single exam foe the two modules making up the integrated course. Students will have to demonstrate knowledge of the components and circuits treated in the lectures, and understanding of their behavior and operation. It is considered important that students be able to solve simple quantitative exercises by hand calculation.
Other information
The course web pages can be found on the Elly platform.
