Nonlinear Control of VSC-HVDC Transmission Converter for Offshore Wind Farm

VSC-HVDC (high voltage direct current based on voltage source converter) is of many advantages compared with traditional HVDC, such as flexible operating ways and reliability, especially in the transmission problem of offshore wind farm. But it is sensitive to AC unbalanced input voltage and instability of wind energy under traditional PI control strategy. This paper adopts dual vector current controller (DVCC) in conjunction with input-output feedback linearization method to design the system. The DVCC can control the positive and negative sequence current respectively. The linearization method makes the double current loop be linear and decoupled To the difficulty of regulating massive PI parameters of multi-inside-loop, we substitute pole placement for PI parameters setting. Namely that it changes the problem of adjusting PI parameters to the one of pole placement. Finally, Simulation study is realized by software of Matlab/Simulink and compare with the traditional control method The results show that the control method of this paper is effective. Copyright (c) 2010 Praise Worthy Prize S.r.l. - All rights reserved