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The symmetry of renewable generations (RGs) and synchronous generations (SGs) is jeopardized by the increase in the penetration RGs, which threatens the secure operation of power systems. Moreover, the control mode transition of RGs during the frequency regulation (FR) process complicates system frequency behaviors. Hence, it is supposed to design a frequency stability constrained unit commitment (FSCUC) model to satisfy the inertia requirements. First, dynamic frequency behaviors are characterized while considering the control mode transition of RGs. Subsequently, the frequency predictive model is developed through a Zero-Order Hold (ZOH) discretization technique. Next, the frequency predictive model is embedded into a stochastic unit commitment (UC). Moreover, a progressive inertia increment (PII)-based solution algorithm is designed to reduce the computational burden. Finally, numerical experiments are conducted in IEEE 24-bus and 118-bus systems to validate the effectiveness of the proposed method. The simulation results show that the frequency stability indices can be improved by 30% by increasing the system inertia by 43% at least with the additional costs of only 0.66%, when compared with existing methods.