Harmonic analysis determined with fast fourier transform on electric networks

viHARMONIC ANALYSIS DETERMINED WITH FAST FOURIERTRANSFORM ON ELECTRIC NETWORKS(M.Sc. Thesis)Özer ŞENYURTGAZ UNIVERSITYINSTITUTE OF SCIENCE AND TECHNOLOGYSeptember 2006ABSTRACTHarmonics affect the energy quality substantially in energy systems. Harmonicsknown as the distortion of an ideal sinusoidal voltage or current waveform areresulted when a sinusoidal waveform is applied to a nonlinear load. Also theymay be resulted from linear or nonlinear loads that are connected to asinusoidal source. Nonlinear elements that have nonlinear current and voltagerelationship are inductors, transformers, photovoltaic systems, converters anddevices having semiconductor elements, e.t.c. Harmonics cause undesired effectson electric networks, the operation of electric devices and the current electricpower. These effects cause additional losses, low efficiency short life time of thedevices and the measurement instruments not to measure correctly besides thedistortion of current and voltage waveforms. In order to determine harmonicsharmonic analyzers and power quality instruments are used.In this study, three phase current and voltage sensors that have been speciallymodified are used.viiThe data obtained from these sensors is transfered to PC via DAQ and FastFourier Transform analysis is realized by using a software. The compliance ofanalysis results to the standarts is interpreted.Science Code : 703.3.012Key Words : Fast fourier transform, harmonic analysisPage Number : 135Adviser : Prof.Dr. Çetin ELMAS