Abstract The fault-ride-through issue for the grid-connected inverter is investigated under unbalanced grid voltage conditions. A new complex power based stationary-frame control strategy is proposed in this paper. Different from the traditional synchronous-frame control methods, our proposal is able to control six variables by combining the oscillating components of active and reactive powers. The coordinate control with the current-limiting capability is achieved with two adjustable variables by integrating the various control objectives. The proposal ensures the continuous adjustment of active and reactive powers, while the grid current operates within the rated value under unbalanced grid voltage conditions. Therefore, the system reliability is enhanced. Finally, the experimental results verify the effectiveness of the proposed solution.
San Guocheng,Qi Hanhong,Wei Yanjun等. Complex Power Based Control Strategy of Grid-Connected Inverter under Unbalanced Grid Voltage Conditions[J]. Transactions of China Electrotechnical Society, 2017, 32(8): 229-236.
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2017, Vol. 32 
