Nonlinear control scheme for VSC-HVDC transmission systems

This paper presents a nonlinear control scheme for VSC-HVDC transmission system. The design of the proposed nonlinear controller has been performed in a rotating reference frame fixed to the grid voltage vectors. The controller is designed to provide high dynamic performance and complete decouple control of active and reactive power. Simulation of the proposed VSC-HVDC control scheme has been performed using Matlab/SimPowSys. Steady state and transient performance under various operating conditions have been examined. The results have been compared with that of a conventional PI control scheme. The nonlinear controller has provided excellent transient and steady state performance as well as complete decouple control of active and reactive power.