Power Electronics and Drives


This subject aims at the acquisition by the students of sufficient knowledge and competence in the area of power electronics in actuators, where the students should be capable to select and/or design the most suitable power converter for a certain application. Students must acquire knowledge about the composition, properties and functioning of the power electronic circuits and devices generally used in electromechanical drives. Students should become able to design and build some circuits, following given specifications. Students should also develop soft skills such as: ability to categorize priorities in the analysis of a technical problem, ability to make structured and clear decisions and improve their written and oral communication skills. The final objective is to contribute to a more interdisciplinary profile of the student, and thus to improve his employability.

General characterization





Responsible teacher

Pedro Miguel Ribeiro Pereira


Weekly - 4

Total - 112

Teaching language



Electronics I + Theorectical Electrotechnics


Ned Mohan, Power Electronics and Drives, MNPERE, 2003

Power Electronics, Converters, Applications and Design, N. Mohan, T. Undeland, W. Robbins, Ed.: John Wiley & Sons Inc., 2002

Power Electronics, Circuits, Devices and Applications, M. Rashid, Editora: Prentice Hall, 1993

Electrônica de Potência (em tradução), Muhammad H. Rashid, Makron Books do Brasil, S. Paulo, 1999

Power Electronics, C. Lander, McGraw-Hill, 1999

Eletrónica Industrial (em tradução) C. Lander, McGraw-Hill Brasil, 2002

Power Electronics, K. Thorborg, Editora: Prentice Hall, 2002

Principles of Power Electronics, J. Kassakian, M. Schlecht, G. Verghese, Editora: Addison Wesley, 1991

Eletrónica de Potência, F. Labrique, J. Santana, Editora: Fundação Gulbenkian, 1991

Teaching method

Scientific principles are explained by the teacher in the theory class, aided by slides. The student’s capacity for oral communication is stimulated through debate around technical and scientific questions.

In practical classes a collection of technical problems is offered to be solved by students based on theoretical class knowledge by calculation. The dialogue between the students is encouraged, and qualitative evaluation is made.

Evaluation method

The assessment is done by designing a project (group (max 5 elements) 30%) and the resolution of two individual written examinations (35% + 35%).

The group assignements will considered as "frequência".

A minimal grade of 9,5 in each evaluation components (project + written examinations) is required.

IMPORTANT NOTE: In the assessement of the assignments, the questions can be asked only to one student and the same grade will apply for the whole group. All students should be aware of all aspects of the work.




Subject matter

. Introduction. Converters, applications. Power electronics of the last generation, intelligent and miniaturized, contactless energy, energy harvesting.

. Converter DC-DC. Pulse modulation, chopper. Converters BUCK, BOOST, BUCK-BOOST, etc. Control modes, voltage and current.

. Electronic devices to control the energy. Thyristor, BJT, MOS, IGBT. Comands and protection.

. Rectifiers, single phase and three-phase. Rectifier as an inverter. AC regulator.

. Voltage inverter and current inverter. Regulation methods.

. Forced commutation converters, including thyristor ones. Voltage and current inverters. Resonant load, Induction heating, ZVS and ZCS. Contactless energy.

. DC e AC motors control. Control V, f, V/f and vector, characteristics. Renewable energy applications. Improving the power factor.