A static var generator (SVG) device solving three-phase voltage imbalance comprises a power grid harmonic voltage and current collection potential transformer (PT) and current transformer (CT), a power grid current and voltage collecting point 1 after removal of harmonic waves, a SVG control cabinet, a semiconductor power device, a capacitor C, an electric reactor L, a protection switch K and a protection resistor R, wherein both harmonic current collected by the power grid harmonic voltage and current collection PT and CT and current, after the removal of harmonic waves, collected by the current and voltage collecting point 1 are input to the SVG control cabinet; the SVG control cabinet outputs a pulse-width modulation (PWM) signal to the semiconductor power device; the semiconductor power device is connected in parallel with the capacitor C and is connected in series with the electric reactor L and the protection switch K; and the protection switch K and the resistor R are connected in parallel. With adoption of the SVG device provided by the utility model, the problem of three-phase voltage imbalance can be effectively solved, and the SVG device is high in response speed, high in tracking precision and capable of greatly raising stability and reliability of the power grid.