General Electrical Engineering
Code
11054
Academic unit
Faculdade de Ciências e Tecnologia
Department
Departamento de Engenharia Electrotécnica
Credits
6.0
Teacher in charge
Anabela Monteiro Gonçalves Pronto
Weekly hours
4
Total hours
60
Teaching language
Português
Objectives
The students, through rigorous scientific deduction, should become aware of the mathematical and physical foundations of applied electrotechnics, namely, of the electric power’s production, distribution and use, and of the composition and characteristics of the most relevant industrial electrical machines.
On the other hand, students must become competent to model, analyse and calculate simple electric power circuits and networks, including balanced three-phase ones. Students will become able to make technically based choices of simple electrical equipments.
Prerequisites
Knowledge adequate to the level of study, namely:
- Fundamentals of electromagnetism (electrical charge, current and voltage).
- Complex numbers.
- Differential and integral calculus.
Subject matter
I. Direct current circuits analysis
1. Eletric resistence, power and energy (a review)
2. Kirchoff laws
II. Alternate current circuit analysis
1. Inductors and capacitors
2. Average value and RMS value of a time variable signal
3. Complex amplitude and fasors
4. RL, RC and RLC circuits
5. Power
6. Power factor correction in an industrial power plant
III. Triphasic circuits analysis
IV. Transformers
1. Principle of operation
2. General equations
3. Equivalent eletrical circuit for ideal and real transformer
4. Applications
V. Assynchronous machine (or, induction machine)
1. Constitution and operation principles as motor and generator
2. Induction motor: mechanical speed, torque, power and efficiency
3. Equivalent electrical circuit of the motor
4. Speed control processes
5. Applications
VI. Energy efficiency and audit
- Energy efficiency definition
- Legal framework
- Electrical energy audit
Bibliography
Vítor Meireles, Circuitos Eléctricos 6ª Edição, LIDEL, 2010.
John Bird, Electrical Circuit Theory and Technology 2nd Ed, Newnes, 2003.
Documentation provided by the lecturer.
Teaching method
The distinct concepts, techniques and theories are explained by the lecturer with the support of slides and practical demonstrations with different equipments.
Students assess their skills through semiautonomous resolution of sets of problems, available in the slides.
Evaluation method
The evaluation method could be one of the following:
a) 2 Tests (MT) and a practical work (TP)
C(MT)= 0,35*MT1 + 0,65*MT2 ≥ 9,5 valores
e
TP ≥ 9,5 valores
The final classification FC is obtained using the following equation:
FC = 0,80*MT + 0,20*TP ≥ 9,5 valores
b) Final Exam (Ex) and a Practical Work (TP)
Exam classification ≥ 9,5 valores
FC = 0,80*Ex. + 0,20*TP ≥ 9,5 valores
In both cases, to be approved, student must have a final classification equal or greater then 9.5 values (in a 0 to 20 scale), and both classification components (MT) and (TP) also equal or greater than 9,5 values (in a 0 to 20 scale).