基于模功率差的风电经直流外送系统源端交流线路纵联保护OA北大核心CSTPCD

The fault characteristics of AC transmission lines are significantly influenced by the access of wind farms and DC systems,rendering traditional relay protection principles inap-plicable.In this paper,we propose a new principle of pilot pro-tection for wind power transmission line based on difference of mode power.Firstly,on the basis of the single unit model,the short-circuit current expression of the doubly-fed wind farm is derived considering the interaction between the various devices of the wind farm.The establishment of a mode power calcula-tion model for the back side system feeding to the transmission line is complemented by incorporating DC system network to-pology.The protective criterion associated with the mode dif-ference and model difference is constructed by utilizing the characteristics of the fault network topology change outside the zone,aiming to identify fault sections.Finally,the proposed method is validated through experimental results conducted on the RT-LAB platform.