With the gradual increase of new energy permeability, a system’s frequency stability problem under high power disturbance is increasingly serious. This limits the absorption capacity of the system's new energy. In order to reasonably plan the access capacity of new energy, it is necessary to evaluate the minimum inertia and primary frequency capacity of the system. Therefore, the interaction between inertia response and primary frequency response under high power disturbance is studied. First, based on the traditional stand-alone model, the expression of the frequency response process considering the frequency dead band is derived. Then, taking the minimum frequency limit after disturbance as the dynamic frequency stability constraint, minimum inertia and primary frequency capacity evaluation models are established, and the minimum power/frequency characteristic and inertia time constant of the system are estimated, and the power curves of inertia and primary frequency responses are calculated and plotted. Finally, the IEEE 10-machine 39-bus model is built in the simulation software of the DIgSILENT PowerFactory. The accuracy and research value of the method of minimum inertia and primary frequency capacity evaluation are verified. This work is supported by the National Natural Science Foundation of China (No. 51977128).