APPARATUS AND METHOD FOR ELIMINATING NOISE OF TRANSMISSION SIGNAL BASED ON WAVELET FILTER TO DETECT EVENTS WHICH INFLUENCE POWER QUALITY INDEX

摘要

The present invention relates to an apparatus and a method for eliminating noise of a transmission signal based on a wavelet filter to detect events having influence on a power quality index. The apparatus for eliminating noise of a transmission signal based on a wavelet filter to detect events having influence on a power quality index includes: an A/D conversion unit for converting a power signal into a digital signal; a wavelet conversion unit for calculating a scale by wavelet-transforming the power signal having been converted into the digital signal; a first calculation unit for calculating a correlation value by using the scale and setting a threshold value; a second calculation unit for setting a mask value by using the threshold value and calculating a new scale by using the mask value; and a reverse-wavelet conversion unit for recovering the new scale into an original signal by wavelet inverse transformation. Noise of the original signal is removed two times when the correlation value is calculated and the new scale is calculated. Therefore, not only linear Gaussian noise but also impulse noise can be effectively eliminated.