Title |
Seamless Mode Transfer of Indirect Current Controlled Parallel Grid-Connected Inverters |
Authors |
Injong Song ; Junsoo Choi ; Kyungbae Lim ; Jaeho Choi |
DOI |
10.6113/TKPE/2019.24.5.334 |
Keywords |
Droop control; Indirect current control; Inverter parallel operation; Seamless mode transfer |
Abstract |
This study proposes the control strategy for the seamless mode transfer of indirect current controlled parallel grid-connected inverters. Under the abnormal grid condition, the grid-connected inverter can convert the operation mode from grid-connected to stand-alone mode to supply power to the local load. For a seamless mode transfer, the time delay problems caused by the accumulated control variable error must be solved, and the indirect current control method has been applied as one of the solutions. In this study, the design of control parameters for the proportional-resonant-based triple-loop indirect current controller and the control strategy for the seamless mode transfer of parallel grid-connected inverters are described and analyzed. The validity of the proposed mode transfer method is verified by the PSiM simulation results. |