Design and implementation of a highly efficient pure sine-wave inverter for photovoltaic applications

Abstract

Due to rapid growth of photovoltaic (PV) power generation, highly efficient and cost effective pure sine wave inverters are greatly demanded in the local market. Based on the simulation result in PSIM software, a low ripple and almost 97% efficient single-phase pure sine-wave inverter for PV application has been designed and implemented which has a total harmonic distortion (THD) of less than 0.6%. Sinusoidal pulse width modulation (SPWM) generated by PIC16F876 Microcontroller is used to control the switching of the inverter power circuit. Error in the output signal is minimized for both inductive and capacitive load by employing a closed loop control scheme that ensures suitable harmonic elimination technique to achieve better performance of the inverter output waveform. To reduce cost we have used low frequency transformer that is available in the local market, which aids to make our design cheaper compared to the design that is based on high frequency transformer. To validate simulation results a prototype has been constructed and tested. Simulation and practical results were compared and both the results conform to each other.