As the installed capacity of wind power continues to increase, the frequency security of the new power system becomes more and more prominent. In order to guarantee the system frequency security and improve the system frequency regulation capability, and to determine a reasonable wind power installed size, a wind power installed capacity optimization model considering dynamic frequency constraints as well as load-side inertia is proposed. First, the dynamic frequency response model with load-side inertia is derived; Secondly, considering the uncertainty of wind power, load and load-side inertia, fuzzy opportunity constraints are introduced, and on the basis of taking into account the dynamic frequency constraints, a wind power installed capacity optimization model considering multiple uncertainty fuzzy opportunity constraints is proposed, and the uncertainty constraints in the model are clearly converted into equivalence classes; Finally, in order to solve the dynamic frequency-constrained nonlinear characteristic problem, the optimization problem is partitioned into the main problem and sub-problems for solving, and the improved 10-machine system is used to verify the validity and feasibility of the proposed model.