Publication in the Diário da República: Aviso n.º 3961/2023 - 29/03/2023
5 ECTS; 2º Ano, 1º Semestre, 60,0 TP , Cód. 626319.
Lecturer
- Carlos Alberto Farinha Ferreira (1)(2)
(1) Docente Responsável
(2) Docente que lecciona
Prerequisites
Not applicable.
Objectives
Provide knowledge of the operation of the main types of mechanical actuators (electromagnetic, piezoelectric, pneumatic, hydraulic, etc.) and their respective mechanical adaptations to the required load. Understand the laws of physics involved. Understand the concept of power electronics for command and control of electromechanical systems.
Program
1. Framework and introduction to generic actuator systems and the subsystems involved.
2. Non-electromagnetic mechanical actuators: piezoelectric, pneumatic, hydraulic, and other systems. Operating principles, subtypes, etc. Production of movement based on a magnetic field (electric machines), magnetic field and its relationship with electrical quantities.
Reviews of electrical machines: operating principles; structure; characteristics; tests; starting and reversal of direction of movement. Relationship between electrical and mechanical quantities.
3. Review of the physics of rectilinear motion: force, velocity, acceleration, mass, power and energy. Rotational motion and the quantities involved: torque, angular velocity and acceleration, moment of inertia. Power and energy. Systems for adapting mechanical parameters: gearboxes, belts, etc., conversion of rotational to linear motion, and efficiency. Requirements for the operating quadrants of mechanical variables for each application.
4. Introduction to power electronics and its use in controlling various types of actuators. Historical evolution. Comparison between linear and switched-mode systems. Switched-mode AC-DC, DC-DC, and DC-AC converters and their operating principles, sizing, and characteristics. Components used: diodes; transistors; IGBTs; thyristors; etc., and their characteristics. Introduction to the concept and calculation of converter efficiency.
5. Introduction to system control and the sensors used.
Evaluation Methodology
Weighted average of the scores obtained in two components:
- written test (TE): 60%;
- laboratory practice (PL) (completion and report): 40%.
In other words: Final grade = (TE*0.6+PL*0.4).
There is no requirement to obtain a minimum score in either part.
Bibliography
- Palma, J. (2008). Accionamentos Electromecânicos de Velocidade Variável. Portugal: Fundação Calouste Gulbenkian
- D. Umans, . e Kingsley Jr., C. e Fitzgerald, A. (2003). Electric Machinery. -: McGraw-Hill
- Robbins, W. e Undeland, T. e Mohan, N. (2008). Power Electronics: Converters, Applications and Design. John Wiley & Sons. -: John Wiley & Sons
Teaching Method
Explanation of concepts, resolution of exercises and practical work in a laboratory context.
Software used in class
Not applicable.
