Electric Drives

Recommended Prerequisites

Transformers and Asynchronous Machines; Power Electronics.

Teaching Methods

Theoretical lectures in the black board and with the aid of Powerpoint slides for the presentation of the concepts, principles and fundamental theories about the topics covered in the curricular unit. Theoretical-practical classes to solve problems and exercises that illustrate the application of the theoretical concepts to real cases in the engineering world. In these classes, some simulations in Matlab/Simulink environment are performed to simulate the behaviour of the systems under study. Laboratory classes to validate the theoretical and practical concepts addressed in the curricular unit.

Learning Outcomes

Presentation of the theoretical concepts underlying the generalized theory of electric machines and its application to the speed control of electric machines. Introduction to the basic concepts of speed/position control of the electric motors used in industry nowadays. Lastly, another goal is that students get a transversal/integrated view of the different knowledge associated to the fields of electric machines and power electronics.

Work Placement(s)

No

Syllabus

Basic concepts of electric drives. Study of the mechanical system: types of mechanical loads, equation of motion, gearboxes and reduction of the moment of inertia to the motor shaft.

Generalized theory of electric machines: space phasor – definition and basic properties; equations of voltage, flux, power and torque of synchronous and asynchronous machines; reference frame transformations; alfa-beta-zero transformation; Park transformation.

Speed variation and scalar control: operation of asynchronous motors at variable frequency; methods of speed control of three-phase induction machines; scalar control. Soft-starters.

Vector control: fundamentals of vector control; rotor field oriented control (RFOC) and direct torque control (DTC) of three-phase induction motors and permanent magnet synchronous motors (PMSMs).

Head Lecturer(s)

Sérgio Manuel Ângelo da Cruz

Assessment Methods

Assessment 1
Other: 20.0%
Project: 25.0%
Exam: 55.0%

Assessment 2
Other: 20.0%
Project: 25.0%
Frequency: 55.0%

Bibliography

H. Abu-Rub, A. Iqbal, J. Guzinski: “High Performance Control of ac Drives with Matlab/Simulink Models”, John Wiley & Sons, 2012.

S. K. Sul: “Control of Electric Machine Drive Systems”, Wiley-IEEE Press, New Jersey, 2011.

I. Boldea, S. A. Nasar: “Electric Drives”, 2nd edition, CRC Press, Boca Raton, 2006.