Research on Joint Control Strategy of Multi-terminal VSC-HVDC Wind Power System with STATCOM

Abstract

With the growing maturity of wind power generation technology and policy support, the grid connection of large-scale wind farms has also been gradually paid attention to. In order to ensure high-precision point of common coupling (PCC) voltage control, high power factor and improve system operation stability, wind speed feedforward control and reactive power limiting link are introduced to limit wind speed and voltage fluctuations, and constant voltage control strategy is improved, Combined with constant power factor control, a joint control strategy is proposed to predict the required active power output of the fan, and then determine the dominant factors affecting voltage fluctuation at this time to select different control strategies. STATCOM devices are put into operation to compensate the voltage of the system to further improve the stability of the system. Based on MATLAB/Simulink platform, the compensation effect of joint strategy and STATCOM in different short circuit fault types of multi-terminal wind power system is verified. The simulation results show that the joint control strategy can simultaneously maintain the stability of PCC point voltage and ensure higher power factor of the unit. STATCOM compensation effect is significant, and can effectively improve power quality.