ECE549 Protection of Power Systems

Fundamental concepts concerning the protection of electrical power systems. Classification of protection methods. Overcurrent-, distance-, differential-, directional- and pilot protection systems.

Protection schemes used in power electrical systems. Protection of power electrical systems against transient phenomena owing to frequency-, voltage-, and power line variations. Operating principles and characteristics of electromagnetic traction- and induction type relays. Impedance and conductivity (mho) type relays. Analog and digital static type relays.

Recent developments of protection systems used in electrical power systems. Application of synchronized phasor measurements. Utilization of modern trends in substation automation.
Protection schemes in transmission lines by using overcurrent-, distance- and directional type relays. Unit protection. Line protection with phase and direction comparison systems. Balance protection. Protection of transformers with relays. Polarized differential protection for transformers.
Protection of electrical machines.

The course aims to provide students with fundamental concepts of protection and operating principles of protection relays for Electricity Systems as well as the methods of protection of the various parts of the Electricity Systems.
Upon completion of the course students will be able to:

• understand the malfunctions in electrical power systems and to design their necessary protection schemes,
• know the individual elements and operating principles of protective devices,
• use and understand in detail the protective devices
• design and implement protection systems for electrical power, deciding for the appropriate protection method as well as for the necessary used equipment.