Detection And Mitigation Of Power Quality Disturbances Using DWT Technique And DVR

Power quality (PQ) is an issue that is becoming increasingly important to electricity consumers at all levels of usage. Improvement of PQ has a positive impact on sustain profitability of the distribution utility on the one hand and customer satisfaction on the other. To improve the power quality problems, the detection of PQ disturbances should be carried out first. The PQ problems vary in a wide range of time & frequency, which make automatic detection of PQ problems often difficult to analyse the cause of occurrence.There are numerous types of PQ disturbances according to IEEE standards that are concerned very often. As it is evident that if there is a problem then there will be a technique to solve that problem. As the same to detect the PQ problems and their disturbances waveform automatically, there are some techniques that are proposed such as Fast Fourier Transform, Short Time Fourier Transform and Wavelet Transform Technique. PQ disturbances also vary in a wide range of time and frequency and Discrete wavelet Transformation(DWT) with Fuzzy classifier have unique ability to examine the signal in time and frequency ranges. In this paper the mitigation of detected power quality problems can be done by the device Dynamic Voltage Restorer (DVR). Keywords—Power quality, Detection of disturbance, Discrete wavelettransform, Fuzzy classifier, DVR.