Abstract：With the increasing in the application of virtual synchronous generator (VSG) technology in micro grid and active distribution network, VSG interface converters operating in parallel are more and more widely. So the problem of equalization in the division had naturally became the focus of research. In this paper, the virtual impedance was introduced at first. Then, taking two VSGs as an example, the principle of equalization of two parallel operations was analyzed. The traditional virtual impedance algorithm cannot adjust the line impedance. A virtual impedance adaptive algorithm was designed. The value of the line impedance will be calculated in real time, and the adaptive virtual impedance can automatically balance the impedance differences of each line, and solved the problem of accurate distribution. At the same time, the setting parameters were given. Finally, Matlab/simulink simulation was carried out under various working conditions to prove the validity and correctness of the proposed algorithm.
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2020, Vol. 35 
