Comparison of Multilevel Converters in Adverse Condition of Load

Inverters with power electronics converters are the main elements used to connect systems that obtain DC (wind energy, photovoltaic, fuel cells, among others) to the grid. On the other hand, most of the loads connected to these networks consist of rectifiers that feed loads whit DC consumptions (electronic equipments). The present work studies the operation characteristics of three phase converters response with two, three, four and five levels, against non-linear conditions of load, i.e., a three-phase non linear load of pulsating type that simulates the behavior of a rectifier connected to the grid. An LC filter connects the inverter and the rectifier. The harmonic contents of the currents of the system are study using of Simulink (MatLab 6.5). The effect of the index of modulation response is analyzed. In addition, the real benefits of a greater number of levels in the converters is established, an important point for the manufactures of these equipments