Abstract

The existing impedance modeling of VSG mostly ignores the influence of different voltage control methods of VSG on the impedance characteristics of the system, which makes its impedance model less universal and accurate. In this paper, amplitude-phase controlled VSG is taken as the research object, and considers the frequency coupling effect, impedance modeling of VSG under three different voltage control modes is carried out by multi-harmonic linearization method. The sweep frequency verification is carried out on the platform of matlab/simulink, which verifies the accuracy of the sequential impedance modeling, and compares the impedance characteristics differences of three VSGs horizontally.