Abstract: According to the characteristics of transient frequency response of the East China Power Grid under various operation modes, an active frequency support strategy is proposed for coastal wind farms. Through the PSCAD/EMTDC-based electromagnetic transient equivalent model of the East China Power grid, the requirements of the East China power grid on the support capacity of wind farms under different penetration of renewable energy, and the basic rules of collaborative inertia response with conventional synchronous generators are given. The simulation results show that when the penetration of renewable energy in the East China Grid is higher than 30%, the inertia response of wind power plays an obvious role in increasing the frequency nadir of the grid, and with the rapid growth of the capacity of coastal wind farms, it is indispensable for wind turbines to provide active inertia support; the virtual inertia time constant of wind turbines should be set around the physical inertia time constant of the wind turbines; when wind turbines are needed to participate in the primary frequency regulation (PFR), the pitch system control of wind turbines and the PFR control of synchronous generators should be co-optimized to avoid frequency oscillation. This article can provide a useful reference for the power grid operation under high penetration of non-synchronous power sources.