Solving Selective Harmonic Elimination Problem in Multilevel Inverter’s using TLBO

Selective harmonic elimination (SHE) in multilevel inverters is an intricate optimization problem that involves a set of nonlinear transcendental equations which have multiple local minima. SHE is an efficient method in elimination of the undesired harmonic components of the inverter’s output voltage. In multilevel inverters, the output voltage THD will be minimized by proper selection of switching angles. There are several procedures to solve the SHE problem. Given that SHE is an optimization problem, the recently developed evolutionary optimization method named Teaching–Learning-Based Optimization (TLBO) is used to solve the nonlinear transcendental equations. TLBO is employed to find optimum switching angles to generate desired voltage value and eliminate specified low order harmonics, simultaneously. Both simulation and experimental results indicate superiority of this approach over the published work using GA and Bee Algorithm in this concept. The feasibility of presented approach is validated by the experiments conducting on a seven-level inverter.

Keywords:

Selective Harmonic Elimination , Teaching–Learning-Based Optimization , Multilevel Inverter