The research on control strategy of cascade STATCOM

The cascade static var generator (SVG) is a nonlinear and variable parameter system with strong coupling. In order to make the cascade SVG device have a good performance in reactive power compensation and capacitor voltage balance control, ADRC is used in the upper layer control and the internal disturbance and external disturbance of the system are observed by the extended state observer in the ADRC, which can improve the immunity of the system. The PI controller is applied to the lower layer control which is phase capacitor voltage balance control. The simulation results show that the proposed control strategy has a good dynamic and static performance.