This Chapter addresses the parameters design problem for converter-based virtual synchronous generators (VSGs), which is crucial for stable operation. Existing methods only consider performance optimization based on the small-signal model or qualitative analysis of large signal stability. However, it remains to be elucidated on how to quantitatively design virtual inertia and damping to ensure transient stability. Sufficient conditions of VSG control parameters for transient synchronization stability are derived using Lyapunov direct method. Then, a systematic feasible parameters region is obtained that satisfies grid code-based transient stability and rate-of-change-of frequency (RoCoF) requirement under large disturbances. As a result, this letter provides a practical reference for control parameters design and engineering application of VSG.