Design and Control of Bypass Diode Multilevel Inverter Using a Single Dc Source

Abstract

The main benefit of using asymmetrical sources in multilevel inverters is that the levels can be created with a minimum number of power sources. However, for most applications it is desirable to use multilevel inverters with a single DC source. In this study, a new topology is proposed to use a single DC source and achieve a low THD. In this topology, bypass diode technique is used and 31 levels are obtained. A small and inexpensive high -frequency link (HFL) is used to obtain the input voltages from a DC source. Nearest Level Control (NLC) and SPWM methods are applied to simulate the output waveform to the reference signal. The power distribution of the HFL voltage levels is designed by calculating according to the NLC method. The proposed topology is implemented in a simulation environment on a resistive load and filter. Experimental results and simulation results were confirmed. In the experimental study, FPGA was used to generate the signals. With the proposed 31-level topology, the output waveform THD value is obtained as 2.7% without filter.