Circuits 2

Code:

L.EEC008

Acronym:

CIR2

Keywords
Classification	Keyword
OFICIAL	Basic Sciences for Electrotechnology

Instance: 2023/2024 - 2S

Active?	Yes
Responsible unit:	Department of Electrical and Computer Engineering
Course/CS Responsible:	Bachelor in Electrical and Computer Engineering

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
L.EEC	373	Syllabus	1	-	6	45,5	162

Teaching language

Portuguese

Objectives

The main objective of the course is to provide students with training on complementary topics of electric circuit analysis, not covered in previous course (Circuits 1). Students first learn the concepts associated to the electrical behavior of capacitors and inductors and the analysis of the step response of first-order RC and RL circuits. After understanding the fundamentals of the dynamic behavior of capacitors and inductors , they learn the techniques for analyzing electric linear circuits in steady state sinusoidal mode (AC), including the analysis of power in AC circuits and the introduction to the three-phase systems. After this, the students learn the concepts associated to the techniques of modeling two-port linear circuits and analyzing electric circuits built with two-port building blocks, including the analysis and design of simple circuits built with operational amplifiers. It is also objective of this course that the students acquire the technical competences for assembling prototypes of simple circuits and for using the laboratory test and measurement equipment for observing and characterizing the dynamic behavior of electric circuits (with emphasis on the oscilloscope and the function generator).

Learning outcomes and competences

After concluding this course the students will be able to:

1. Explain the relationships between voltage, current and energy in capacitors and inductors, and analyze the step response of RC and RL circuits.

2. Analyze electric circuits in sinusoidal steady state using the phasorial transform and the concepts of electric impedance, and characterize and calculate the power transformed by electric elements in sinusoidal steady state (active, reactive, apparent and complex).

3. Explain the concept and advantages of the three-phase system in power distribution networks and analyze three-phase circuits, including power calculations.

4. Apply the linear two-port model to characterize amplifiers and analyze simple circuits with ideal operational amplifiers.

5. Use software tools for simulation of electric circuits (SPICE-based) and test and measurement laboratory equipment, in particular the oscilloscope.

Working method

Presencial

Pre-requirements (prior knowledge) and co-requirements (common knowledge)

The students should have been enrolled in the preceding course Circuits 1, and should be, preferably, approved in that curricular unit.

Program

1. Capacitors and inductors
2. Step response of first-order electric circuits built with one capacitor or one inductor (RC and RL).
3. Sinusoidal signals, phasorial transform and the phasorial relationships in passive elements; the concept of impedance and admittance.
4. Analysis of linear electric circuits in sinusoidal steady state.
5. Power in electric circuits in sinusoidal steady state.
6. Three-phase circuits.
7. Linear two-port circuits and analysis of circuits with ideal operational amplifiers.

Mandatory literature

J. A. Brandão Faria; Análise de Circuitos, IST Press, 2013. ISBN: 978-989-8481-50-4

Complementary Bibliography

Vítor Cancela Meireles; Circuitos Eléctricos, Lidel, 2020. ISBN: 978-972-757-586-2
Nilsson James W.; Electric circuits. ISBN: 0-201-55707-X

Comments from the literature

List of supplementary bibliography for all contents of the program provided by the regent and accessible through the SIGARRA.

Teaching methods and learning activities

The curricular unit is organized in theoretical classes (1.5h) and laboratory classes (2h). The theoretical classes are used for presenting the syllabus topics and also to illustrate practical problem and solve examples of exercises. In the laboratory classes the students solve exercises addressing the matters presented previously in the theoretical classes and perform experimental laboratory works. In these works, real electric circuits are built and analyzed, and simulation tools are used to analyze circuits for which it is not feasible their physical construction in the laboratory (for example, three-phase circuits).

Software

Octave
LTSpice
MultiSim (simulador de circuitos elétricos)

keywords

Technological sciences > Engineering > Electrical engineering

Evaluation Type

Distributed evaluation with final exam

Assessment Components

Designation	Weight (%)
Exame	60,00
Teste	20,00
Trabalho laboratorial	20,00
Total:	100,00

Amount of time allocated to each course unit

Designation	Time (hours)
Estudo autónomo	100,00
Frequência das aulas	45,50
Trabalho laboratorial	16,50
Total:	162,00

Eligibility for exams

The students must participate in at least 3 of the 4 minitests and all the laboratory assignments and attend at least 75% of the practical classes.

 

Calculation formula of final grade

The final grade (FG) is the sum of the classification of a final written exam given at the end of the course (FE) and the classification of the distributed evaluation formed by a set of mini-tests (MT) to be done in the laboratorial classes and a laboratory assignment (LA).

The final grade is calculated as FG = 0.6 FE + 0.2 MT + 0.2 LA

To obtain a passing grade it is necessary to satisfy simultaneously the following conditions:
1. fulfill the requirements to obtain the "frequencia" status
2. obtain a final grade FG equal or superior to 10 points;
3. obtain a minimum grade of 40% for the sum of the mini test and laboratory grades (MT+LA);
4. obtain a minimum grade of 40% in the final exam (FE).

Examinations or Special Assignments

None.

Internship work/project

None.

Special assessment (TE, DA, ...)

The students exempt of attending the practical classes will not have to register in a section neither to attend the practical classes, but they will have to participate in the minitest and the set of laboratory exercises selected for grading. These students will have to fulfill all the other criteria for obtaining approval:
1. ...
2. obtain a final grade FG equal or superior to 10 points;
3. obtain a minimum grade of 40% for the sum of the mini test and laboratory grades (MT+LA);
4. obtain a minimum grade of 40% in the final exam (FE).

Classification improvement

The grade of the final exam and the minitest (60%+20% of the final grade) can be improved by taking the 2nd exam ("recurso"), maintaining the grades of the laboratory works. The grades obtained in the laboratory classes can be improved by repeating these evaluation activites in the next edition of the course.

 

Observations

The students who attended Circuits 2 in the 2022/2023 academic year and failed, but who obtained a distributed assessment greater than 40%, will be able to maintain this distributed assessment classification in the current academic year without having to repeat the distributed assessment points. If they choose to repeat the distributed assessment activities in the current academic year, the best AD grade between 2022/2023 and 2023/2024 will be considered for the final classification. If the 2022/2023 AD grade is maintained, it will always be in its entirety and the grades for the mini-tests and laboratory work will not be considered separately.

The 4 mini-assessment tests will be carried out in PL classes on the weeks of March 4th, April 1st, April 22nd and May 20th. Of the results obtained in these 4 tests, only the 3 best classifications will be considered for the evaluation grade distributed. An unjustified absence from one of these tests results in a classification of zero; students who are absent and who present the appropriate justification for their absence at DEEC services will have the classification part relating to this test included in the final exam.

In two of the PL classes, in the weeks of April 15th and May 13th, 2 practical laboratory assignments will be carried out, worth 50% of the distributed assessment classification (AD). Unjustified absence from these laboratory work implies a classification of zero values. Students who miss laboratory work and who provide justification for their absence at DEEC services will have the opportunity to carry out this laboratory work in an extra session that will be held in the last week of classes.

All assessment activities carried out in PL classes will be carried out in the classes in which the students are enrolled.