When we are talking about electric power systems, we should pay attention to the devices that protect them. They have been, and they always will be there as „silent sentinels” at every substation, every transformer, electric motors, generators etc. to ensure failure-free operation of the power system: their work is (in case of a fault) to cease the faulty state as soon as possible and restore normal conditions if possible.
The transmission lines of the high voltage grid are mainly protected by line distance protection devices against overcurrents (and therefore thermal overload) caused by faults. These devices work by measuring positive sequence impedances, so they can calculate the distance and type of the fault even if the power system has more feeders in itself. After that, the command will be given to break the circuit in one or three phase depending on the fault’s type.
Protecta Co. Ltd. has been working with designing, development and production of protection devices for more than half a century. The company has recently given to the Technical University two of its brand new product, the EuroProt+. This microprocessor-based device can be used for many protection issues. In our case the line distance protecion function will be examined.
In today’s education beside the theory it is important that the students learn how to use (or at least have some practical knowledge about) the instruments they may encounter later at work. To do so, we need up-to-date equipment in the laboratory in order to replace the old ones.
In this thesis I will give an introduction to line distance protection, the Protecta EuroProt+ family and the devices and set-up of the old/new measurement that will take place in the laboratory of the Power Systems and Environment Group.