Comparative analysis of different harmonics mitigation techniques

Abstract

Electronic equipments have a great potential in contributing to the harmonic problems. With the widespread use of these equipments, the harmonic problems can become a major distortion to the power system if it‟s not treating properly. Today, various techniques to mitigate the harmonic problems are available. But, not all techniques are superior to solve the problems. Many factors are contributing in selection of the mitigation techniques such as types of harmonic sources, the salient order of harmonic, location installation of the technique and cost factors. Thus, the analysis on the system must be done properly before introduced or installed any mitigation technique, otherwise, another problems (e.g resonance phenomenon) may arise. The harmonic analysis focused on this study is at networks that consist of battery charger and UPS as the main contribution to the harmonic problems. Four harmonic mitigation techniques are proposed to solve the problems, single tuned filter tuned at 5th order, 5th and 7th order tuned filter, 3rd order C-type filter and phase shift transformer. After all the parameters regarding to respective techniques are determined, the proposed techniques are then performed using ETAP software for harmonic analysis purposes. IEEE-519 1992 limits standard is used as a guideline in this study. The results obtained shows that, all mitigation techniques are able to suppress the THDI below the limits but at some individual harmonic number and power factor resultant, not satisfied the limits. In term of electrical and cost benefits, the 5th and 7th order tuned filter is chosen as a best technique to mitigate harmonic problems in this study. This method manage to reduced the THDI almost 83% (from 26.7% to 4.55% of THDI) and correct the power factor up to 0.98.