| Title |
High Frequency Noise Reduction Method Using a Newly Designed Low-pass Filter in DFT-Based Phasor Estimation |
| Authors |
백민우(Baek, Min-Woo) ; 강상희(Kang, Sang-Hee) |
| DOI |
https://doi.org/10.5370/KIEE.2017.66.6.898 |
| Keywords |
High frequency noise ; Cut-off frequency ; Low-pass filter ; DFT ; Phasor estimation |
| Abstract |
DFT(Discrete Fourier Transform) is one of the most widely used method to estimate the phasor of a relaying signal. The harmonics are eliminated by the DFT. However, high frequency components, except for harmonics, are not removed and cause an error in DFT-based phasor estimation process. This paper suggests high frequency noise reduction method by using a newly designed low-pass filter to estimate a signal phasor. When selecting a stop-band cut-off frequency of the low-pass filter, high frequency components generated by faults are considered. To reduce the phasor estimation delay caused by a low-pass filter, this paper proposes a low-pass filter whose settling time is reduced. An adverse effect of high frequency noise on DFT-based phasor estimation is reduced. To evaluate the performance of the proposed method, signals which are collected under a fault condition at a 345[kV] transmission system modeled by EMTP-RV are used. |