Publication in the Diário da República: Aviso n.º 23391/2023 de 4/12/2023
8 ECTS; 1º Ano, 2º Semestre, 66,0 TP , Cód. 61627.
Lecturer
- Raul Manuel Domingos Monteiro (1)
(1) Docente Responsável
(2) Docente que lecciona
Prerequisites
Not applicable.
Objectives
To enable students to analyze simple electrical circuits and installations, in sinusoidal alternating current, single-phase and three-phase, and to introduce basic concepts of Electromagnetism and a simplified study of the single-phase electrical transformer.
Program
1. Fundamental quantities and components of electrical circuits; definitions. 1.1 Electric Current. Electric voltage. Forms of electric current: unidirectional current and variable-direction current; alternating current. 1.2 International system of units; prefixes. 2. Single-phase sinusoidal alternating current. 2.1 Necessity of alternating current. 2.2 Characteristic quantities. Mathematical representation. Phase angle between sinusoidal quantities of the same frequency; particular values. Vector representation. 2.3 Characterization of circuit elements in sinusoidal alternating current regime: resistance, coil, and capacitor; voltage-current relationships in the time domain, instantaneous power, average or active power, and stored energy. 2.4 Complex numbers as a tool for solving electrical circuits in sinusoidal alternating current; elementary operations with complex numbers. 2.5 Symbolic representation of sinusoidal alternating quantities using phasors. Time domain and frequency domain. Operations with sinusoidal functions in the time domain and corresponding operations in the frequency domain. 2.6 Concept of impedance and admittance; reactance, conductance, and susceptance. Voltage-current relationships of resistance, coil, and capacitor in the frequency domain. Kirchhoff's laws in the frequency domain. Association of impedances and admittances. 2.7 Active, reactive, and apparent power. Power factor. Power triangle. Calculation of power and power factor for elements connected in parallel (single-phase electrical installation). Power factor compensation. 2.8 Resonance and resonance condition. Examples of the resonance phenomenon. Maximum power transfer; impedance matching. 3. Three-phase sinusoidal alternating current. 3.1 Three-phase voltage system. Mathematical and vector representation. Star and delta connection. 3.2 Balanced and unbalanced systems. 3.3 Power in three-phase systems. Boucherot's method. Power factor compensation in three-phase systems; practical considerations. 4. Introduction to electromagnetism. 4.1 Electric current and magnetic field. Magnetic circuits. 4.2 Operating principle of the electric transformer. 4.3 Conclusions.
Evaluation Methodology
Tests throughout the semester or final exam. Passing the course unit is achieved if the average grade in the tests or the grade in the exam is greater than or equal to 9.5 out of 20.
Bibliography
- Hayt, W. e Kemmerly, J. e Durbin, S. (2008). Análise de Circuitos em Engenharia. McGraw-Hill: McGraw-Hill
- O'Malley, J. (2011). Schaum's Outline of Basic Circuit Analysis. McGraw-Hill: McGraw-Hill
- Oliveira Albuquerque, R. (2008). Análise de Circuitos em Corrente Alternada. Editora Érica: Editora Érica
Teaching Method
Theoretical and practical classes for presenting the subject matter and for solving problems and conducting laboratory demonstrations. .
Software used in class
Not applicable.
