Power System Protection Laboratory

The laboratory is intended for the measurement and testing of protective relays and of the equipment used to integrate protection into the power system.

Its main purpose is to support the education of students. The laboratory also serves the needs of applied research.

Two courses are taught in the Power System Protection Laboratory: Protective Relays in the Power System, and Protection Systems in the Power System.

Protective Relays in the Power System is a compulsory course taken by all students of the Electric Power Engineering programme in the third year of their bachelor's studies. On completing the course, students gain knowledge of the operating principles of the various types of protective relay — from electromechanical relays through to modern digital relays — as well as of the methods used to protect power lines and electrical machines.

In Protection Systems in the Power System, students acquire the fundamentals of designing protection systems for individual power system components, and equally for complete installations such as the protection systems of generating units, substations, and transmission and distribution networks.

The following activities are carried out in the laboratory:

The laboratory is equipped with various types of current and voltage instrument transformers and with current and voltage sensors, on which students verify correct operation. An incorrect choice or malfunction of a current transformer (CT) or voltage transformer (VT) for a given application markedly affects the operation of the protective relay. Verifying and understanding the operating principle of each instrument transformer is therefore a very important aspect of power system protection.

The laboratory allows secondary injection testing of digital protective relays using Omicron CMC 156, COMPANO 100 and SEL 4000 test sets. Testing digital relays begins with a calculation stage, in which students apply their theoretical knowledge to determine numerically the individual parameters required for correct relay settings. They then enter these values into the relay, either manually or using the ACSELERATOR QUICKSET software, and test the relay using Omicron Test Universe together with the Omicron CMC 156, COMPANO 100 or SEL 4000.

The laboratory is equipped with a wide range of digital protective relays, as well as with real MV switchgear cubicles incorporating a protective relay, a disconnector and a circuit breaker.

The Power System Protection Laboratory is currently equipped with three multifunction workbenches on which students can deepen their knowledge of setting digital protective relays. The relay types used are those commonly deployed in utility and industrial practice to protect a given section of network or item of equipment.