Multi-terminal HVDC (MTDC) system based on modular multilevel converters (MMCs) is being built in European transmission power grids. Among many open engineering challenges, one of particular concern with MTDC systems is the small-signal stabiilty during both the design and the lifecycle of the projects. In this project, a toolbox that can perform the small-signal stability study based on the black-box modelling of MMCs will be developed. Recommendations on the dynamic specification of the dc terminal of the MMC will be given.