Harmonics Elimination in Multilevel Inverter Using Linear Fuzzy Regression

Multilevel inverters supplied from equal and constant dc sources almost don-t exist in practical applications. The variation of the dc sources affects the values of the switching angles required for each specific harmonic profile, as well as increases the difficulty of the harmonic elimination-s equations. This paper presents an extremely fast optimal solution of harmonic elimination of multilevel inverters with non-equal dc sources using Tanaka's fuzzy linear regression formulation. A set of mathematical equations describing the general output waveform of the multilevel inverter with nonequal dc sources is formulated. Fuzzy linear regression is then employed to compute the optimal solution set of switching angles.

Authors:

• A. K. Al-Othman
• H. A. Al-Mekhaizim

Keywords:

• Multilevel converters
• harmonics
• pulse widthmodulation (PWM)
• optimal control.

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