کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
400212 | 1438780 | 2010 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A wavelet-based method to discriminate internal faults from inrush currents using correlation coefficient A wavelet-based method to discriminate internal faults from inrush currents using correlation coefficient](/preview/png/400212.png)
In this paper a new method based on discrete wavelet transform and correlation coefficient is presented for digital differential protection. The algorithm includes offline and online operations. In offline operation, discrete wavelet transform is used to decompose typical three-phase differential currents for inrush current. Then an index is defined and computed. The index is based on the sum of the energy of detail coefficients at level 5 of three-phase differential currents at each half cycle. The online operation consists of capturing the three-phase differential currents using 10 kHz sampling rate, decomposing it by db1. Finally, the inrush current and internal fault is detected based on correlation coefficients of the computed index of pre-stored typical inrush current and a recorded indistinct signal. The effectiveness of the approach is tested using numerous inrush and internal fault currents. Simulations are used to confirm the aptness and the capability of the proposed method to discriminate inrush current from internal fault.
Journal: International Journal of Electrical Power & Energy Systems - Volume 32, Issue 7, September 2010, Pages 788–793