As an active three-phase unbalanced load compensation device, the static var generator (SVG) can control the magnitude, amplitude and phase of the AC-side voltage, thus achieving flexible control of reactive power and compensation of voltage sag, but its application results will be affected by the grid parameters. Recent studies often do not quantitatively analyze the impact of fault depth and fault duration on the device management result in the case of voltage sag. In this paper, the working principle of SVG equipment is analyzed, and the modeling analysis and control design of three-phase SVG devices are carried out; the mechanism of voltage sag acting in the main and control circuits is analyzed, the main causes leading to equipment instability are quantitatively analyzed, and the different effects of different depths and duration of voltage sags on SVG equipment are analyzed. Finally, the conclusion is verified by simulation.

Circuit Analysis;Sensitivity;Simulation;SVG;Voltage Sag