Design and development of a SPWM single phase inverter

Abstract

This paper presents the design and development of a SPWM single phase inverter. A microcontroller is used to generate sinusoidal pulse width modulation (SPWM) signal for the inverter switches. An appropriate command from the microcontroller is generated to control the frequency switching pulse of the single phase inverter. This inverter is design to be either for stand- alone or for grid connected from a direct supply of photovoltaic cell or from battery. The switching frequency that was used in this design is 5 kHz with amplitude modulation ratio 1. In this paper concept of the single phase inverter and it relation with the microcontroller is first reviewed. Subsequently approach and methods are discussed including circuit configuration and modulation technique. Finally simulation and experimental results are discussed. The simulation and experimental result shows that the total harmonic distortion (THD) for voltage and current is less than 3% for 300W application. The efficiency of the development SPWM single phase inverter is 88%.