Abstract:Aimed at the problem of conventional PI controller with the contradiction between the rapid and smooth when it was used for the SVC control system, a design method of the improved nonlinear norm transformation PI controller was proposed. In front of the conventional PI controller’s proportion and integral, different nonlinear norm transformations were added to form nonlinear PI controller. Then, this nonlinear PI controller was used for the voltage regulator unit design in SVC control system. The simulation results showed that the improved nonlinear norm transformation PI controller has faster response speed and better stability than nonlinear norm transformation PI, in addition, the SVC control system based on improved nonlinear norm transformation PI controller has the advantages of faster response speed, smaller over-modulation, better static and dynamic performance comparing with conventional PI controller.