Design and Simulation of an Inverter with High Frequency Sinusoidal PWM Switching Technique for Harmonic Reduction in a Standalone/ Utility Grid Synchronized Photovoltaic System

Inverters are one of the major parts of any Photovoltaic Systems which are intended to feed power to any isolated standalone ac loads or to synchronize with the utility power grid systems. This paper discusses the design and simulation of a typical 1kW experimental precise sinusoidal Photovoltaic inverter which is intended to feed ac power at a standard 50Hz frequency to a mini grid powered by Photovoltaic solar cells. The very well-known and popular sinusoidal pulse width modulation (SPWM) technique with very high carrier frequency (in the order of kHz) has been chosen as the control scheme of the inverter by which it is also possible to synchronize the module to feed power on the 1-phase utility power grid. The high carrier frequency switching scheme enables to design a low pass smoothing filter for harmonic elimination resulting a reduction in Total Harmonic Distortion (THD) with small sized inductors and capacitors. As a prototype, the proposed circuit has been designed to supply small ac power, where the same design can be adopted and implemented to feed high power on the same grid only by increasing the device power ratings.