Electrical Drives

Course description

Components of electrical drives. Past, present and future trends in drive systems. Stationary and transient states of electrical drives. Characteristics of electric motors, typical load torques. Moments of inertia of complex drive systems, accelerating torque. Electrical and mechanical transients, stability problem of drive system. Types of electric motors, their supplying, connection, selecting and cooling.

Electric motors in drive systems:

DC (commutator and brushless) machines. Induction (slip ring, squirrel cage, solid rotor) machines. Synchronous (field winding, permanent magnet, reluctance) machines. Principles of operation, speed-torque characteristics and possibilities of their modifications. Starting and breaking dynamics, classical and modern principles of speed and motion control. 4Q operation.

Methods for selecting the drive types. Sizing and dimensioning electric motors. Thermal conditions, cooling principles, standard and user defined duty types. Reactive power compensation.

Energy efficient motors and drive systems – technical and economical aspects, principles of energy savings. Electrical drives with increased reliability and fault tolerant operation. Standard protection of drive systems.

Course is carried out on study programme

Elektrotehnika 2. stopnja

Objectives and competences

Student will be provided with the knowledge and procedures for design, optimization and maintenance of grid supplied and controlled electrical drives in industrial and traction systems. They will be able to choose and carry out energy efficient, reliable and cost effective electrical drives.

Learning and teaching methods

The lectures provide a theoretical background on discussed topics. A complete study material is available to the students.

Successful practical work on laboratory excercises, which take place in smaller groups, enables prior acquaintance of the students with computational and demo tasks.

Intended learning outcomes

After successful completion of the course, students should be able to:

– Evaluate state-of-the-art and perspectives of electrical drives.

– Explain the difference between grid supplied and inverter fed electrical drives.

– Clarify physical operational principles of basic drive types.

– Describe main components of integrated drive systems.

– Explain in details behaviour of electrical motor and mechanical load connection.

– Research the influence of control parameters on static and dynamic characteristics of drive motors.

– Establish the optimal selection of electrical motor type.

– Estimate the importance of energy efficiency operation of controlled electrical drives.

– Recognize the significance of reliability and safety in drive operation.

– Manipulate with modern types of electrical drives which are most used in industry practice.

Reference nosilca

  1. GAŠPARIN, Lovrenc, FIŠER, Rastko. Cogging torque sensitivity to permanent magnet tolerance combinations. Archives of electical engineering, 2013, vol. 62, no. 3, str. 449-46
  2. FIŠER, Rastko, LAVRIČ, Henrik, BUGEZA, Miroslav, MAKUC, Danilo. Computations of magnetic field anomalies in synchronous generator due to rotor excitaton coil faults. IEEE transactions on magnetics, May 2013, vol. 49, no. 5, str. 2303-2306.
  3. DROBNIČ, Klemen, NEMEC, Mitja, FIŠER, Rastko, AMBROŽIČ, Vanja. Simplified detection of broken rotor bars in induction motors controlled in field reference frame. Control engineering practice, [Print ed.], Aug. 2012, vol. 20, no. 8, str. 761-769.
  4. GAŠPARIN, Lovrenc, ČERNIGOJ, Andrej, FIŠER, Rastko. Additional cogging torque components due to asymmetry in stator back iron of PM synchronous motors. Compel, 2011, vol. 30, no. 3, str. 894-905.
  5. NEMEC, Mitja, DROBNIČ, Klemen, NEDELJKOVIĆ, David, FIŠER, Rastko, AMBROŽIČ, Vanja. Detection of broken bars in induction motor through the analysis of supply voltage modulation. IEEE transactions on industrial electronics, [Print ed.], Aug. 2010, vol. 57, no. 8, str. 2879-2888.

Study materials

1. R. Fišer, Interno študijsko gradivo v pisni in elektronski obliki (Internal study material).

2.  J. Weidauer, R. Messer, Electrical Drives – Principles, Planning, Applications, Solutions,

     Publicis Publishing, Siemens, 2014

3.  A. Hughes, B. Drury, Electric Motors and Drives – Fundamentals, Types, Applications, 4th Ed.,

     Newness, Elsevier, 2013.

4.  B. Drury, The Control Techniques Drives and Controls Handbook, 2nd Ed., IET, 2009.

5.  A. Emadi, Energy-Efficient Electric Motors, Marcel Dekker, 2005.

6.  T. Wildi, Electrical Machines, Drives, and Power Systems, Pearson, Prentice Hall, 2006.

Bodi na tekočem

Univerza v Ljubljani, Fakulteta za elektrotehniko, Tržaška cesta 25, 1000 Ljubljana

E:  dekanat@fe.uni-lj.si T:  01 4768 411