The Design and Implementation of Photovoltaic Grid-connected Simulating Device Based on FPGA

A kind of photovoltaic grid-connected device is designed based on FPGA in this paper. The system can achieve maximum power point tracking (MPPT) and the auto-adjustment of frequency and phase in grid-connecting. It consists of auxiliary fly-back switch power, full-bridge DC/AC converter, LC filter and some protecting circuit etc. The device possesses the high speed of MPPT adjustment and tracking of frequency and phase, with frequency ranging from 30 Hz to 60 Hz, deviation below 0.4%, stability above 99.5%, converting efficiency nearly 80%. The system runs stably and reliably and can be used in grid-connecting projects.