Design of Three Phase Grid-Connected Inverter Based on Grid-Voltage Oriented Control

Aiming at the topology of three phase grid-connected inverter, the principle of dq-axis current decoupling is deduced in detail based on state equation. The current loop regulation and the three phase grid-connected control system based on grid voltage orientation are simulated by using Matlab/Simulink. The experimental platform is built with DSP as the control core, and the off-grid experiment and grid-connected experiment are carried out respectively. The simulation results are consistent with the experimental results, which show that the amplitude and phase of grid-connected current can be controlled and are in the same frequency and phase with the grid voltage. So the transmission of energy from the DC side to the power side can be realized with the unit power factor.