Double fed induction generator（DFIG） is the main type of wind power generation

thus the electromechanical transient simulation model of DFIG is the basis for studying the interaction between the scale wind power farm and power grid.We established an overall architecture of DFIG’s electromechanical transient simulation model according to the DFIG’s active and reactive power regulation control as well as different function partition in DFIG interfacing with the AC grid.Model structure and relationships of functions are analyzed in detail.The applicability and limitation of the model are specified.The disturbed power characteristics of wind farm accessing into the power grid are studied

and the influences of voltage feedback control

voltage fluctuation rate and amplitude on the power characteristic are also studied.In the accessing of scale wind power and photovoltaic（PV） power farm into the Qinghai-Haixi pwer grid

measures are proposed to reduce the tripping threat of PV power generation under low voltage by utilizing the reactive power features of wind power pooling bus.Simulation results verify the effectiveness of the measures.