Large-scale grid-connection of photovoltaic (PV) generation causes the power system to face the problem of insufficient inertia and insufficient frequency modulation capability. One of the important means to solve this problem is to take part in grid frequency regulation actively. On the basis of spare certain active power, this paper puts forward the active power-frequency droop control strategy. By modifying the original control structure of the inverter, PV generation actively takes part in the grid frequency primary regulation. In order to achieve non-error adjustment of frequency, this paper further proposes a secondary frequency regulation control strategy that adapts to different grid-side AGC control modes (constant frequency control mode, constant tie line power control mode and tie line power frequency deviation control mode). The effectiveness and feasibility of the control strategies are verified based on the PSCAD/EMTDC simulation platform.