Design and Analysis of a Single Phase 650A Transformer-Less Inverter For Solar PV Power Application

Abstract

This paper presents a single phase boost Photovoltaic (PV) inverter system and its control implementation. In order to achieve low cost, easy control, high efficiency and high reliability. The inverter employs push pull switch mode converter, an H bridge inverter, an automatic changeover dual battery bank and an RF remote control circuit unit. The switching technique of the proposed inverter consists of a combination of sinusoidal pulse width modulation (SPWM) and square wave oscillator along with grid synchronization condition. As the suggested method is entirely transformer less, it ridiculously reduces total harmonic distortion (THD) which is less than 0.1%, minimizes size and swells with inverter efficiency up to 98% which can be used in our homes, offices and schools for lightening and charging. Most of the PV systems are designed with transformer for safety purpose with galvanic isolation. However, the transformer is big, heavy and expensive. Also, it reduces the overall frequency of the conversion stage. Generally PV inverter with transformer is having efficiency around 92%–94% only. To overcome these problems, transformer less PV system is introduced. It is smaller, lighter, cheaper and higher in efficiency. A capacitance conversion circuit provides a nearly constant output current which stabilize system rapidly and reduces harmonics generated by inverter. Overall performance of the proposed inverter is simulated through the proteus. The simulation results are analyzed through PROTEUS and MATLAB software which produced a pure sinusoidal waveform as the output voltage. A 650VA prototype was designed and construction, tested, simulated and Experimental results are provided to verify the validity and performance of the circuit operations and current control.