A Cooperative Imbalance Compensation Method for Distributed-Generation Interface Converters

Distributed generation has attracted great attention in recent years, thanks to the progress in new-generation technologies and advanced power electronics. The Microgrid has been a successful example by integrating various generation sources with the existing power distribution network through power electronic converters. Microgrid converters are required to operate in a decentralized fashion, and power-frequency and reactive-power-voltage droop controls have been adopted for this purpose. In this paper, a droop control technique for imbalance compensation within the three-phase ac distributed generation system is proposed for Microgrid converters. The proposed technique allows even sharing of imbalance current among various converters and can thus be seamlessly integrated with the existing active-power-frequency and reactive-power-voltage droop controls to improve the power quality within the distributed power system. Its control functionalities are discussed, and simulation and laboratory test results are also presented to validate the proposed method.