A micro power quality management technology based on grid-connected inverter

According to power quality problems generated in micro-grid operation, micro-source grid-connected inverter control method based on an advanced f - Q, V - Q droop characteristic control method is put forward in the paper. By voltage frequency and amplitude restoration link, both of external voltage loop and internal current loop adopt feed-forward approximate decoupling control strategy. It not only improves the dynamic response performance of the micro-grid, but also balances system power when micro-grid switched from grid-connected mode to island mode fast and suppresses voltage sag phenomenon generated by power unbalance of micro-grid. At the same time, it avoids impulse current during the switch process, improving the reliability of the micro-grid operation. Simulation results proved the effectiveness of the proposed method.