Uncertainty-Adaptive Line Voltage Optimization in Cascaded H-Bridge Inverters

This paper proposes a novel line voltage-derived formulation to reduce and eliminate third-order harmonics due to uncertainty in DC link voltages of cascaded H -Bridge (CHB) inverters. These converters produce third-order harmonics because the DC voltage that owes to these converters may vary from one line of the 3 -phase inverter. The efficiency of the converter and lowering those unwanted harmonics are optimized using the Genetic Algorithm (GA) optimization method. By finding the best patterns of switching, it is possible to remove as many unwanted harmonics and have voltage at line frequencies all the time during changes in DC voltages. This is demonstrated by the simulation results, which show that this technique works well in improving output power quality and reducing third harmonic order.