Abstract：This paper proposes a novel control scheme of three-phase grid-connected inverters (GCIs), in which a proportional plus resonant (PR) regulator is adopted. The PR regulator, which is tuned at the synchronous angular frequency, can be applied in the stationary αβ reference frame directly. Furthermore, the PR regulator does not require any decomposition of positive- and negative-sequence currents. It will improve the performance of the grid-connected inverters during the transient process of the unbalanced grid voltage fault condition, and its fault ride through capability will be enhanced as well. Compared with the conventional PI control scheme and dual-PI control scheme, the correctness of the theoretical analysis and the feasibility of the unbalanced control scheme with the PR current regulator are validated by detailed experimental tests.
章玮, 王宏胜, 任远, 胡家兵, 贺益康. 不对称电网电压条件下三相并网型逆变器的控制[J]. 电工技术学报, 2010, 25(12): 103-110.
Zhang Wei, Wang Hongsheng, Ren Yuan, Hu Jiabing, He Yikang. Investigation on Control of Three-Phase Grid-Connected Inverters Under Unbalanced Grid Voltage Conditions. Transactions of China Electrotechnical Society, 2010, 25(12): 103-110.
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2010, Vol. 25 
