Fuzzy Logic Controller For Minimization Of Harmonics In Multilevel Inverter

Vol. 3  Issue 2
Year:2014
Issue:May-Jul
Title:Fuzzy Logic Controller For Minimization Of Harmonics In Multilevel Inverter
Author Name:S. Sudha and C. Santhakumar
Synopsis:
A new approach for modulation of an 11-level cascade multilevel inverter using selective harmonic elimination is presented in this paper. The direct current sources feeding the multilevel inverter are considered to be varying in time, and the switching angles are adapted to the dc source variation. This method uses Newton Raphson method to obtain switching angles offline for different dc source values. Then, fuzzy logic controllers are used to determine the switching angles that correspond to the real time values of the dc sources for each phase. This implies that each one of the dc sources of this topology can have different values at anytime, but the output fundamental voltage will stay constant and the harmonic content will still meet the specifications. The modulating switching angles are updated at each cycle of the output fundamental voltage. This paper gives details on the method in addition to simulation and experimental results.