Design of Photovoltaic Grid-connected Inverter Based on SPWM Hybrid Modulation

A photovoltaic grid-connected inverter has been developed based on analog and digital control technologies. This inverter integrates modules such as a DC - DC boost unit, a DC - AC full - bridge inverter unit, a communication unit, and an upper - computer display unit. It uses a boost circuit with SG3525 as the core and an inverter circuit with DSP TMS320F28335 as the core as the common main circuit of the inverter, and adopts a SPWM single - double - polarity hybrid modulation control strategy. This not only significantly improves the overall conversion efficiency and stability of the photovoltaic power generation system, but also provides a reliable and efficient solution for large - scale clean energy grid connection.