Performance analysis of wavelet transform de-noising technique in partial discharge signal based on various types of mother wavelet via labview software

Longer service period of insulation system in high voltage has cause major problem to the high voltage equipment which typically due to ageing and deterioration. This will lead to the occurrence of Partial Discharge (PD) and immediate failure of the power system. Nowadays, PD measurement is applied to detect the occurrences of the PD. However, PD measurement has faced problem of unwanted noise in the measured PD signal. Therefore, Discrete Wavelet Transform (DWT) de-noising technique is widely used due to viable and superior characteristic of DWT in rejecting different kinds of noise from measured PD signal. Thus, the performance analysis of DWTde-noising technique based on various decomposition level and different type of mother wavelet, such as Haar, Daubechies, Coiflets, Symlets and Biorthogonal via LabVIEW software were carried out. The performance of denoising technique is analysed based on Mean Square Error (MSE) of the PD signal in order to select the optimum mother wavelet in the de-noising process. Minimum MSE will promising the optimum mother wavelet. Based on the result, bior5.5 wavelet had the lowest MSE value, thus selected as the most optimum for PD de-noising application.