ELECTROMECHANICAL CONVERTERS

lelec1310  2020-2021  Louvain-la-Neuve

ELECTROMECHANICAL CONVERTERS
Due to the COVID-19 crisis, the information below is subject to change, in particular that concerning the teaching mode (presential, distance or in a comodal or hybrid format).
5 credits
30.0 h + 30.0 h
Q2
Teacher(s)
Dehez Bruno;
Language
French
Prerequisites
- LEPL 1202 (Physics)
- LELEC 1370 (Measurements and electrical circuits)

The prerequisite(s) for this Teaching Unit (Unité d’enseignement – UE) for the programmes/courses that offer this Teaching Unit are specified at the end of this sheet.
Main themes
- Single-phase and three-phase transformers
- General Theory of electromechanical converters
- Rotating field machines
- Asynchronous machines
- Synchronous machines
- DC Machines
Aims

At the end of this learning unit, the student is able to :

1 In consideration of the reference table AA of the program " Master's degree civil engineer mechanics ", this course contributes to the development, to the acquisition and to the evaluation of the following experiences of learning:
Contribution of the course to the program objectives
Axis 1 (1.1, 1.2, 1.3), Axis 3 (3.3), Axis 5 (5.4)
Specific learning outcomes of the course
At the end of the course, students will be able to:
- Link the fundamental concepts (Faraday's law, energy and magnetic co-energy, ...) to the general equations of an electromechanical converter;
- Build the steady state model (equations and equivalent circuit) of a rotating field machine, an asynchronous machine (three or single-phase), a synchronous machine and a DC machine;
- Build the steady state model (equations and equivalent circuit) of the transformer (single or three phase);
- Experimentally determine the parameters of these models
- Use these models to predict operating conditions of these devices depending on the supply and the load.
In addition, the student will be able to:
- Determine and interpret the characteristic quantities of an electromechanical converter or transformer;
- Identify the main electromechanical converters structures;
- Establish the conditions guaranteeing the energy conversion in an electromechanical converter;
- Explain the principle of the universal motor;
- Explain the ways to increase the starting torque, to reduce the starting current or to vary the speed of an electromechanical converter;
- Explain how to connect and control an alternator on the grid.
 
Content
- Introduction, reminder of the basics of electrical circuits (1h)
- The single-phase transformers (4h): structure, fundamental laws, models of the ideal transformer, of the perfect transformer and of the real transformer, on load operation, experimental parameter identification
- Three-phase transformers (1 hour): structure, connection modes, single-phase equivalent circuit
- The general theory of electromechanical converters (2 hours): classification, structure, basic assumptions, electrical and mechanical equations, magnetic energy and co-energy, electromagnetic torque
- Rotating field machines (4h): general design features, equations, supply, equivalent circuit, saturation, synchronous and asynchronous operating modes, main structures of rotating field machines
- The three-phase asynchronous machine (5h): specific design features, equations, equivalent circuit, phasor diagram (the circle diagram), torque-speed characteristic, operating point, saturation, iron losses, power and efficiency, practical problems (current-starting torque vs efficiency, speed control), specific applications (phase shifter and induction regulator, electrical axis - Selsyn, synchronoscope, Leblanc damper)
- The single-phase induction motor (1 hour): structure, principle and equations
- The synchronous machine (4h): specific design features, equations, equivalent circuits, phasor diagram, operating point (stability), active and reactive power control, connection and control of an alternator on the grid
- The DC machine (2h): specific design features, structure, equations, operating and excitation modes, starting, universal motor
- Introduction, reminder of the basics of electrical circuits (1h)
- The single-phase transformers (4h): structure, fundamental laws, models of the ideal transformer, of the perfect transformer and of the real transformer, on load operation, experimental parameter identification
- Three-phase transformers (1 hour): structure, connection modes, single-phase equivalent circuit
- The general theory of electromechanical converters (2 hours): classification, structure, basic assumptions, electrical and mechanical equations, magnetic energy and co-energy, electromagnetic torque
- Rotating field machines (4h): general design features, equations, supply, equivalent circuit, saturation, synchronous and asynchronous operating modes, main structures of rotating field machines
- The three-phase asynchronous machine (5h): specific design features, equations, equivalent circuit, phasor diagram (the circle diagram), torque-speed characteristic, operating point, saturation, iron losses, power and efficiency, practical problems (current-starting torque vs efficiency, speed control), specific applications (phase shifter and induction regulator, electrical axis - Selsyn, synchronoscope, Leblanc damper)
- The single-phase induction motor (1 hour): structure, principle and equations
- The synchronous machine (4h): specific design features, equations, equivalent circuits, phasor diagram, operating point (stability), active and reactive power control, connection and control of an alternator on the grid
- The DC machine (2h): specific design features, structure, equations, operating and excitation modes, starting, universal motor
Teaching methods

Due to the COVID-19 crisis, the information in this section is particularly likely to change.

Teaching is organized in:
  • 13 lectures;
  • 7 supervised exercise sessions;
  • 2 practical lab sessions;
  • 3 virtual lab sessions.
The practical lab sessions are carried out in groups of 4 or 5 students and lead to the writing of a synthesis report.
Virtual lab sessions are carried out autonomously online (via iCampus), but consultancy session are nevertheless organized.
The Moodle platform also includes a series of multiple-choice questions allowing the students to evaluate and deepen their understanding of key concepts for the course. It also includes a series of illustrations for better appropriating these concepts.
Depending on the health situation, the teaching activities can be organized in face-to-face, remotly, using videoconference, or a mix of both.
Evaluation methods

Due to the COVID-19 crisis, the information in this section is particularly likely to change.

Students will be evaluated:
- Collectively based on the reports of the 2 practical labs performed in groups of 4 to 5 students during the semester;
- Individually based on a written exam for the exercise part of the course and an oral exam for the theoretical part.
For the written exam, no documents are allowed except a form of two A4 pages written by the student and containing only formulas, diagrams or graphs.
Depending on the health situation, these exams can be organized remotely. In this particular case, if a problem is noted in a copy of the written part of the exam (suspicion of fraud or technical problem) or when it is submitted (when downloading or equivalent), an oral exam, independent from the one related to the theoretical part, may be organized in addition and/or in replacement of the written assessment.
Bibliography
- Transparents du cours
- Enoncés et solutionnaires d'exercices
- Notices de laboratoires et laboratoires virtuels
- Illustrations et compléments au cours
- QCM
- Livre de référence :
B. Dehez, D. Grenier, F. Labrique, E. Matagne, Electromécanique. Principes physiques, Principaux Convertisseurs, Principales applications, Presses universitaires de Louvain, 1er éd., 372p.
Faculty or entity
ELEC


Programmes / formations proposant cette unité d'enseignement (UE)

Title of the programme
Sigle
Credits
Prerequisites
Aims
Specialization track in Electricity

Minor in Electricity

Minor in Engineering Sciences: Electricity (only available for reenrolment)