Design of an energy function based fuzzy tuning controller for HVDC links

Abstract

The paper introduces an energy function based fuzzy tuning method for the controller parameters of an HVDC transmission link. The test system, a point to point DC link, was subjected to various small and large disturbances to examine the effectiveness of the proposed method. The DC current error and its derivative are taken as the two principal signals to generate the change in the proportional and the integral gains of the rectifier current regulator according to a fuzzy rule base. Computer simulation results confirm the superiority of the proposed adaptive fuzzy controllers over the conventional fixed gain controllers in damping out the transient oscillations in HVDC links connected to weak AC systems.