Complementos de Eletrónica

Objectives

To give the students a detailed knowledge on the area of power electronics covering the single phase transformer, output power stages, power converters and control with negative feedback. The course covers the analysis of the operation of the different systems as well as their project and simulation through appropriate software. The connection with real applications in research physics laboratories is established.

Syllabus

I. Study of the monophasic transformer. Loss less, perfect and ideal transformers. Iron nucleus transformer. Steinmetz scheme. Project of the power supply transformer. II. Output amplifier stages working in class A, B and AB. Biasing, transfer function, efficiency. Power transistors and power dissipation. Class AB output stage with power MOS-FETS. III. Electronic power converters. Construction with the H Bridge switch of types AC-DC, DC-AC, DC-DC and AC-AC. Switching type DC-DC converters: Buck, Boost and Buck-Boost converters. Functioning analysis, conduction modes, output voltage and ripple, efficiency. Output voltage control with feedback. Bridge converters: half bridge and full bridge. Converters with transformer; bridge converter, push- pull, forward and flyback converters. IV. Power control with feedback. Introduction to the dynamic behaviour of linear and time invariant systems with feedback. Application in the control of: Converters, DC motors, heating and refrigeration.

Prerequisites

The students should have pre-knowledge of Circuits Theory and Electronic Fundamentals.

Cross Competence Component

Inovative and criative thought (criativity, strategic thought, problem sovolving aproaches): use and transposition of the information/knowledge received from the teachers to work in the laboratory. Interpersonal skils (oral presentations, team work): optimization of the team work in the laboratory activity. Personal Skils (self-discipline, enthusiasm, persistence, self-motivation): organization of the laboratory work. Global citizenship (tolerence, open mindedness, respect diversity, intercultural understanding): laboratory work developed with students from different countries. Media and Information Literacy (hability to locate, access, and evaluate information on the internet): Internet search activity developed within the context of the laboratory work. The evaluation of the soft skils is made within the context of the laboratory activity.

Laboratorial Component

-Determination of the electrical characteristics of the single-phase transformer and analysis of the magnetic properties of the core material. -Analysis of the loaded power transformer. -Analysis and simulation of a class A output stage with bipolar power transistors. -Analysis and simulation of a class B output stage with bipolar transistors. -Analysis and simulation of operation of the boost converter. -Design, construction and testing of a negative feedback control system.

Ethical Principles

All members of a group are responsible for the group’s work In any assessment, every student shall honestly disclose any help received and sources used. In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.