Micro Controller Based Single-Phase Seven-Level Inverter for Photo Voltaic System

The given paper presents the hardware design and implementation micro-controller based single phase seven level inverter for Photo- Voltaic application. The input to the given inverter is a DC source (Vdc) and it is capable of producing output of seven level (Vdc, 2Vdc/3, Vdc/3, 0, -Vdc, -Vdc/3, -Vdc/3). The switching devices used are IRF840 MOSFET and diodes. Control circuit for implementing the H-bridge inverter is done by using the micro-controller. The system proposed in given paper is having lesser number of switching devices which reduces the complexity of the circuit and a simple control circuit is employed using the micro-controller. The multi level inverters provides nearly sinusoidal output waveform, output current with refined harmonic profile and switching losses that are less than the conventional two level inverter and hence smaller filter size is required. The main application of this system is directly delivering the Photovoltaic generated energy to the power system networks by using this seven level inverter (SLI) as grid connected inverters.