Power Quality Disturbances and Protective Relays on Transmission Lines

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2011 by IJETT Journal
Volume-2 Issue-2                          
Year of Publication : 2011
Authors : Shaik Sharif,N. Asha Latha,Shaik Dawood


Shaik Sharif,N. Asha Latha,Shaik Dawood."Power Quality Disturbances and Protective Relays on Transmission Lines". International Journal of Engineering Trends and Technology (IJETT),V2(2):55-60 Sep to Oct 2011. ISSN:2231-5381. www.ijettjournal.org. Published by Seventh Sense Research Group.


Power quality concerns the effect of voltage disturbances on end - user equipment and of current disturbances on network componen ts. Power system protection concerns the detection of faults in the system from measured voltages and currents. However, non - fault voltage and current disturbances may lead to the inadvertent detection of a fault in the same way as voltage disturbances may lead to the tripping of end - user equipment. Starting from the principles (algorithms) of the relays, a quantification approach is developed to assess the disturbance impact on the relays. The quantification is based on the relay response after processing the disturbance signals by relay filters. This makes it possible to quantify the disturbance impact by the consequences caused by the disturbances, other than by the signal waveforms of the disturbances. Power transmission lines protection is one of the mo st important concerns for power utilities. Different types of faults occur on Transmission Line. From the transient phenomena, faults on transmission lines need to be detected, classified, located accurately, and cleared as fast as possible. Identification and classification of faults on transmission line are essential for relaying decision and auto - reclosing requirements. This dissertation presents a novel Wavelet - Fuzzy combined approach for digital relaying. An algorithm based on wavelet multi - resolution analysis (MRA) is used for classification of transmission faults for quick restoration of power supply and for improving the transient stability


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Multi - Resolution Analysis (MRA) , Fuzzy Inference System (FIS).