ABSTRACT:
With the development in
science and engineering the power system protection field also get advanced
which includes the development of relays .the relays journey started by
electromechanical then solid state and now digital and numerical relays .An
economical and feasible solution to investigate the performance of relays and
protection system offered by modeling of protective relays .Distance relay is
one of the effective protective relays that are used for the protection of
extra high voltage transmission lines. Distance relays are considered of the
high speed class and can provide protection. To detect the fault on transmission
lines many distance relays are used but for long transmission line mho relay is
most suited. The proposed work is about designing of numerical mho relay in
MATLAB / SIMULINK to be used for distance protection schemes of long distance
transmission lines with better result and characteristics. The required mho
relay algorithm is evaluated by using MATLAB to model the power system under
different fault condition and simulate it by using phasor based method
available in MATLAB simulation. Thus the modeling and simulation of numerical
mho relay gives the improved result and greatly enhance the performance of mho
relay
KEYWORDS:
1. Distance protection
2. Numerical relays
3. Matlab/Simulink
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
This work presents a detailed phasor model for a distance relay of mho characteristics. Mho relays are inherently directional so there is no need for directional elements in the relay model. Here the developed simulation is evaluated for line to line fault on the system, and the results found as Simulation results of different faults regarding type and position show clearly the accurate performance of the developed distance relay model. From results it is seen that speed of operation of numerical mho relay is faster than impedance relay. The model versatility, adaptability and applicability promote it for use in power system simulators. Also, it can be used as a training tool to help users understand how a distance relay works and how settings are performed.
REFERENCES:
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