Electrical Machines I
Part of this Programme
Level of Qualification|Semesters|ECTS
Bachelor | Semestral | 6
Year | Type of course unit | Language
3 |Mandatory |Português
Total of Working Hours | Duration of Contact (hours)
168 | 75
Recommended complementary curricular units
Prerequisites and co-requisites
1. Introduction to electrical machines and magnetic circuits. 2. Transformers (T): ideal T.; Transformation of electrical circuit elements; Equivalent circuit of an industrial T. (R, L and Core losses); Nominal capacity; Values "per unit"; Determination of parameters; T. in charge. Voltage regulation; Yield; T. for polyphase power systems; Groups of connections and vectorial analysis of three-phase T.; Parallel operation; T. Specials. 3. Continuous Chain Machine (MCC); Magnetic system; Armature windings; System collector-brushes; Electromagnetic torque and induced voltage; Equivalent circuit; Reversibility of the MCC. Operation in permanent regime; Binary-velocity characteristic; Characteristic curves of DC machines (independent excitation, branch, series and composite - short and long derivation); Magnetic armature reaction; Switching; Auxiliary poles; Energetic balance.
This unit intends to develop: A - the ability to master the concepts related to single-phase and three-phase transformers ("master" is used to: A1 - develop the ability to identify the basic components and parameters most relevant to the definition of electrical characteristics of transformers and, A2 - to develop the capacity of, for desired electrical characteristics, to dimension these parameters and to project their implementation); B - the ability to master the concepts related to the DC Machine. Types of machines, and drives ("mastering" is employed in the sense of: - developing the ability to identify the types, base components and parameters most relevant to the definition of the electrical and mechanical characteristics of each MCC; , for desired electrical characteristics, choose the appropriate type of machine and size these parameters and design their implementation).
Knowledge, abilities and skills to be acquired
It is advisable that students have already acquired the knowledge taught in curricular units of calculation, algebra and electromagnetism.
Teaching methodologies and assessment
Five hours of face-to-face lectures per week, of which 2h are theoretical, expository, 2h theoretical-practical, for analytical resolution of examples and specific problems and 1h of laboratory, for demonstration and experimental verification of theoretical concepts taught. There are two modalities of evaluation: Continuous assessment - two frequencies in the normal period of classes, each with a weight of 35% in the final evaluation. For this modality also contributes the evaluation obtained in the laboratory component with a weight of 30%. It is noted that, in this area, approval is only possible if the average obtained in the two frequencies is greater than or equal to 10 values. Assessment by exam: the best classified exam grade is counted. There are two normal exam times to which all enrolled students may have access and a special time to which only those students who meet the criteria for accessing the special time defined in the reg. of evaluation
* Apontamentos dados na disciplina de Máquinas Eléctricas I ¿ Hugo Marques.
* Electric Machinery, A.E.Fitzgerald; Northeastearn University; Charles Kingsley Jr, Stephen D. Umans; Sixth Edition - McGraw Hill.
* Analysis of Electric Machinery and Drive Systems; Paul C. Krause, Oleg Wasynczuk, Scott D. Sudhoff; Second Edition - IEEE Press.
* Three Phase Transformer Winding Configurations and Differential Relay Compensation, L. Lawhead, R. Hamilton, J. Horak; Basler Electric Company.
* Principles of Electric Machines and Power Electronics, Sen, P.C; Jonh Wiley & Sons, NY 1989.
* Electric Machinery Fundamentals, S. J. Chapman; 3rd edition, McGraw Hill Int. Ed, 1989.
* Industrial Electricity, John Nadon and Bert Gelmine, D. Van Nostrand Comp. Inc.