Assessment of multi-level inverters for low and medium voltage applications

This paper presents the assessment of diode clamped multilevel inverters (DCMLI) and cascaded multi-level inverter (CMLI). For each topology its main features and its implementation using MATLAB-Simulink® are presented. From a case study the inverters are compared taking into account the number of elements required, the waveform of the output voltage, the total harmonic distortion on the voltage signal (THDv), the individual harmonic content and the behavior of the THDv as a function of the output voltage. The simulations show that the improved DCMLI inverter has better waveform results and lower THDv for a given voltage range.