A new simplified multilevel inverter topology for grid-connected application

Multilevel inverter performance is high compared to the conventional two level inverters due to their reduced harmonic distortion, lower electromagnetic interference. However the main drawback of multilevel inverter is increased number of switches, complex pulse width modulation control and balancing of capacitor voltages. This paper proposes a single phase seven level inverter for grid connected system. The proposed inverter topology consists of fewer components with low complexity gate drives and control signals. An LC filter is used to limit the switching current ripple by providing high attenuation of harmonic and high dynamic performance. This paper also presents the most relevant control and modulation methods by a new reference/carrier based PWM scheme employing three similar reference signals with an offset of magnitude equal to the amplitude of the carrier signal. The entire system is numerically simulated using MATLAB/SIMULINK and the simulation results are presented.