Research on control strategy of photovoltaic grid connected converter under voltage distortion

Aiming at the problem that the power grid voltage distortion caused by non-linear loads such as electric arc furnace loads in the distributed power grid causes photovoltaics to fail to be effectively connected to the grid, a dynamic analysis of the distribution network voltage is required and a new phase-locked loop based technology is used. The control strategy of the grid-connected converter is to reduce the harmonic distortion rate when the photovoltaic grid is connected to the grid and improve the quality of the grid-connected current and grid-connected voltage. A typical dynamic model of the electric arc furnace and a Photovoltaic system model are established. By analyzing the impact of the electric arc furnace model on the grid-connected photovoltaic grid-connected converter with a traditional phase-locked loop when it is connected to the grid, a self-regulating Control Strategy of SOGI’s Phase-locked Loop Photovoltaic Grid-connected Converter. Finally, the arc furnace simulation module and photovoltaic system simulation module were customized through the PSCAD / EMTDC software platform, and the feasibility of the control strategy was verified through simulation analysis.