Research On Single-Phase Transformerless PV Inverter

As the worldwide fossil energy exhaustion and the growing environmental problems, research and development of renewable energy power generation becomes the subject of concern to all mankind, photovoltaic technology emerged and rapidly developed in this context.At present, most researches of photovoltaic inverter are focus on innovation or improvement in control, driving and detecting. This issue aims to, studying the optimized structure and high performance control strategy of grid-connected PV system, combining power electronics with control technology, making the system highly-efficient usage of solar energy, injecting the ideal current waveform into grid, providing ideal power for grid and providing theoretical foundation and technical support for the solar photovoltaic grid-connected inverter products.This paper firstly summarizes the prospects and development of photovoltaic grid technology in China and describes the characteristics of common voltage-type inverter circuits. Then analyzes the electromagnetic compatibility of two conventional three-level inverter circuits on common-mode interrupts and the dc injected, and conducts a simulation using MATLAB. Provide an new inverter circuit structure on that basis. Finally gives the implementation of system, designs two conventional and a new schematic experimental prototypes based on diode-clamped three-level inverter circuit , and DSP-based algorithm for the analysis of SPWM equivalent area and achieve a three-level inverter circuit optocoupler isolation driving using 6N136 and IR2110,eventually be three topology inverter output waveform.