KSSVG is connected in parallel to the grid through a reactor or a transformer, which is equivalent to a variable reactive current source. By adjusting the amplitude and phase of the output voltage on the AC side of the inverter, the required reactive power can be quickly absorbed or emitted to achieve rapid The purpose of dynamic adjustment of reactive power. On the one hand, it effectively solves the problem of harmonic interference switching the shunt capacitor device. On the other hand, it can suppress or control harmonics according to the actual requirements of users, and improve power quality.