Asymmetric MLDCL Inverter with Reduced Number of DC Sources Using LEN for PV Applications

An asymmetric Multilevel DC-Link Inverter (MLDCLI) with Level Enhancing Network (LEN) is proposed for Photovoltaic (PV) Application is presented in this paper. LEN made up of four switches and a DC source. The proposed topology requires 7+log
2
((N+3)/3) switches and log
2
((N+3)/3) DC sources for generating N
L
levels. The MLDCLI-LEN requires a lesser DC source count in comparison to the existing topologies for a fixed number of levels. A detailed comparison is provided in terms of component count. A 45-level asymmetrical MLDCLI-LEN is simulated using MATLAB/SIMULINK tool. Phase Disposition Level Shift Pulse Width Modulation (PD-LSPWM) technique by considering a carrier frequency is equal to the fundamental frequency (50Hz). A prototype model of 45- level MLDCLI-LEN is built in the laboratory using dSPACE1104. The output voltage waveform has a Total Harmonic Distortion (THD) of 2.4 %.