Power Electronics and Drives – (M.Sc.)

Contents

1st semester

This semester is common for the three electrical specialisations in Energy Engineering, Electrical Power Systems and High Voltage Engineering (EPSH), Power Electronics and Drives (PED) and Wind Power Systems (WPS). For students with a Bachelor of Science (BSc) degree from Aalborg University, the credit of the project work is 15 ECTS, whereas it is only 10 ECTS (INTRO project) for students with a BSc degree from another university.

The project technical topics are identical, but students from another university have one extra course which includes theory of Problem Based Learning (PBL). This method is the primary teaching method used at Aalborg University, and it is applied in all projects. The documentation of the project work is also different:

Students with a BSc degree from Aalborg University should:

* Document the project work by a paper, a poster and a presentation at an internal conference (CES) together with an appendix report, all in English.

Students with a BSc degree from another university should:

* Document the project work by a project report written in English.

1st Semester Project for Students with a BSc Degree from Aalborg University: Dynamics in Electrical Energy Engineering

On this semester, focus is on a problem where the dynamics of an electrical energy system or electrical apparatus must be analysed. This problem may, for instance, be in the subject area of electrical power systems, electrical drive systems, wind power systems or a combination of these. In such systems, short circuits, starting procedures, control issues, etc., demand that the dynamic performance of the systems must be studied. The chosen system must be analysed and modelled. Finally, some experimental verification of the system, a model of the system or parts of the system should be carried out in the laboratory.

Project examples:

* Use of the induction machine as drive on an electric vehicle
* Non-linear model of 3-phase distribution transformer
* Model of grid connected wind turbine generator.

1st Semester INTRO Project for Students with a BSc Degree form Another University than Aalborg University: Problem-based Project-organised Learning in Dynamics in Electrical Energy Engineering

The purpose of this semester is to give the students a comprehension of the Problem-Based Learning method applied at Aalborg University. Focus is to give the students experience in carrying out project work in connection with problems in the subject area of electrical energy engineering. The students will write a project report documenting their project work. Knowledge will be given to students in subject areas related to the chosen specialisation. The technical problem for this semester is the dynamics of an electrical energy system or electrical apparatus. This problem may for instance be in the subject area of electrical power systems, electrical drive systems, wind power systems or a combination of these. In such systems, short circuits, starting procedures, control issues, etc., demand that the dynamic performance of the systems must be studied. The chosen system must be analysed and modelled. Finally, some experimental verification of the system, a model of the system or parts of the system should be carried out in the laboratory.

The assessment of the INTRO semester project is a stop-test. It is a precondition that this project is passed to be able to continue on the 2nd semester of the MSc study.

Project examples:

* Characterisation of photovoltaic panels
* Improvements to the domestic energy supply - wind energy, solar energy, or UPS apparatus
* Electric bicycle for indoors use.

2nd semester: Control of Converter-fed AC Drives

2nd semester projects will study modelling, analysis, simulation and control of an electric system which must include a power electronic converter and an electric machine. The system being studied will be described using a dynamic model and analysed in order to design a suitable digital controller for the whole or parts of the system. Dynamic interaction between the different parts of the system will be studied. All, or part of the system, will be built and tested in the laboratory, including real-time implementation of controllers in e.g. digital signal processors, to provide verification of the models used.

Project examples

* Wide-bandwidth current control of PWM inverter-fed induction motor drive with LC filter
* Sensorless control of a brushless motor drive system
* Energy efficient control of permanent-magnet motor for electric vehicle
* Control of wide-bandwidth actuator for application in robotics.

3rd semester: Optimisation, Diagnosis and Control of Power Electronic Drives or Converters

The objective of this semester is to strengthen skills related to design of power electronic converters and systems. The project should be based upon a power electronic drive or a converter system to which an optimisation, control or diagnostic system is to be set up. First, the system is analysed and modelled and then different system identification methods can, for instance, be applied to determine the parameters of the system. The system model is verified by simulations and data time series from either a real system or a laboratory set-up. Based on the set-up model, the optimisation, control or diagnostic system is set up to improve the performance of the system, either with regard to the power output, the energy efficiency, the life time extraction, fault detections or alike and the system, or parts hereof, should be implemented and verified experimentally in the laboratory.

To practice scientific communication skills, the project result, or parts of it, must be published in an article written in English. This article is to be presented at an internal seminar (CES).

Courses are offered of which 10 ECTS are to be chosen. The courses may vary from year to year, depending on the number of students of the various specialisations, the on-going projects and the research performed at the Department of Energy Technology. Further, courses from other universities might be used as electable courses. However, the two following courses are always available:

* Neural network and Fuzzy logic - 5 ECTS
* System identification and diagnosis - 5 ECTS

4th Semester Master's Thesis in Power Electronics and Drives

The Master's Thesis may study new subjects or be an extension of the project work of previous semesters. The subject matter will remain in the area of power electronics and drives. The project may be of theoretical or experimental nature, and will often be in collaboration with an industrial company or other research institution performing research in the area of power electronics and drives. Alternatively, it may support one or more research projects at the Department of Energy Technology. Often, students write scientific papers reporting the work of their Master's Thesis. As courses are not normally offered on this semester, the entire semester is dedicated to the thesis work.

Examples of Master's Theses:

* Single-stage three-phase solar cell power electronic converter
* High-efficiency magnetic gear box with a high gearing ratio
* Design of power electronic grid interface system for large-scale wind turbines
* Sensor-less control of a permanent magnet motor drive using signal injection techniques.