Harmonics effects on power systems and analyse by pspice

SUMMARY Key Words: Harmonic, harmonic producing sources, harmonic effect, harmonic analysis, harmonic limit, filter. Harmonic components are the whole number multiples of the fundamental frequency component. Harmonics are causing distortions at the fundamental frequency component. Non linear loads are injecting produced harmonic current and voltage to the supply and hence disturbing the power system energy quality. In this work, firstly the harmonics are investigated theoretically and the effects of these to the network and the surrounding consumers. In the following sections the methods for harmonics analysis are explained. Further more a computer programme was developed and with the help of this program fourier analysis of different shapes of waveforms has been caried out. Different total harmonic distortion for various countries has been compared and the filters for keeping the THD in the mentioned limits has been studied in details. Also the disadvantages and advantages of these filter has been comparatively examined. The advanteges of using the active and passive filters together has been pointed out. Finally, simulation results of a passive filter example has been shown.