Multiple Power Quality Events Analysis

Abstract

PQ events have become a serious concern for the power system operations. newlineLiterature in this thesis revolves around different signal processing and classification newlinetechniques for recognition of PQ events. Volterra series based techniques are the most newlinesuitable choice for non-linear and non-stationary signal leaving behind all other techniques newlinebased on basis functions like Fourier transform, STFT, S-transform and Wavelet transform newlineetc. Therefore, this work revolves around Volterra analysis of PQ events in the power newlinesystem. Then features are extracted which act as input to the interval type-2 fuzzy based newlineclassifier and finally the results are compared with other methods which show high newlineaccuracy of proposed novel technique for detection and classification of power quality newlineevents. newlineA novel technique of adaptive finite element method based on sparse features newlinebased approach explored for analysis of power quality events. The role of adaptive finite newlineelement method is to generate a unique feature set and type-2 fuzzy system for the purpose newlineof classification of power quality disturbances with minimum error. The concept of newlinestiffness matrix is applied on power quality events. The type-2 fuzzy system utilizes the newlineconcept of membership functions to classify the single and multiple power quality events newlineand then the proposed method is compared with other methods and finally with traditional newlinetype-I fuzzy logic approach for classification of power quality events. The results revealed newlinethat the novel methodology of adaptive FEM can reduce the computation time significantly newlinewith high accuracy. newlineIn today s time, maintaining the power quality (PQ) in the electrical system is a newlinemajor issue between the end user and the utilities due to increase in demand of sensitive newlinemicroprocessor based controllers, heavy non-linear loads and solid state equipment newlineattached to the grid.