Single-phase seven-level inverter with multilevel boost converter for solar photovoltaic systems

Multilevel inverters are a viable solution for meeting rising power needs at both the generating and utility levels. The magnitude of the voltages produced in the solar photovoltaic (PV) systems is also low. This paper presents a two-stage seven-level inverter for solar PV systems with a three-level boost converter for boosting the input voltage for the inverter. The proposed inverter is compact in size and is capable of delivering a peak voltage magnitude of six times the input voltage. The control signals for this topology are generated using conventional sinusoidal pulse-width modulation techniques. The proposed topology is modular and can also be cascaded to produce higher voltage levels, or it can be configured to operate as a seven-level inverter with a higher output voltage gain, as dictated by the control signals. A detailed comparison of the proposed topology with conventional inverter topologies are also presented. The simulations are carried out in MATLAB/Simulink environment and the results are presented.