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• A novel frequency constrained unit commitment for asynchronous interconnected system with high share of renewable energy sources. • Modeling of bidirectional transmission power in steady state and frequency support in transient state of VSC HVDC. • A method is proposed that utilizes an intelligent sampling-based SVM to convexify the nonlinear expression of the maximum frequency deviation constraints. • The uncertainty of renewable energy sources is addressed using the distributionally robust chance constrained approach. • A two-stage decomposition algorithm for solving the frequency constrained unit commitment. The increasing share of renewable energy source (RES) poses a challenge to the frequency security of the power system. Frequency constrained unit commitment (FCUC) serves as an effective measure to address this challenge at the operational level. This paper introduces a novel FCUC model applicable to the asynchronous interconnected system connected by voltage source converter based HVDC (VSC HVDC), fully taking into account the frequency support capability of VSC HVDC in order to reduce the demand for synchronous generators' inertia and reserve while ensuring frequency security, thereby lowering operating costs. Additionally, the uncertainty of RES is also considered. The constraint expressions for three frequency indicators are derived based on a system frequency response model that includes frequency support from VSC HVDC. The proposed model optimizes unit commitment, generation and reserve dispatch and VSC HVDC transmission power and frequency response parameters, while addressing RES uncertainty using the distributionally robust chance constrained approach. In response to the highly nonlinear characteristics of the maximum frequency derivation (MFD) constraints, we propose an intelligent sampling-based support vector machine to convexify the MFD constraints and introduce a two-stage decomposition algorithm for solving the model. The effectiveness of the proposed model is demonstrated based on a modified IEEE RTS-79 system. [ABSTRACT FROM AUTHOR]