Microcontroller based single-phase simplified seven-level inverter for PV system

This paper proposes the hardware design and implementation of a Microcontroller based single-phase simplified seven-level inverter for PV system. Multilevel inverters tender high power capability, associated with lower output harmonics and lower turn-off losses. This work informs a multilevel inverter for PV system using an H-bridge output stage with bidirectional auxiliary switches. The inverter is capable of producing seven levels of output-voltage levels (V_dc, 2V_dc /3, V_dc /3, 0, -V_dc /3, - 2V_dc /3 - V_dc) from the DC supply voltage. The control circuit necessary for multilevel inverter operation is implemented using an ATMEL AT89S52 Microcontroller, reducing overall system cost and complexity. Theoretical predictions are validated using simulation in MATLAB SIMULINK, and satisfactory circuit operation is proved with experimental tests performed on an experimental model.