Abstract
This paper presents a comprehensive modelling approach to obtain a small-signal model of a Modular Multilevel Converter (MMC)-based High Voltage Direct Current (HVDC) link interfacing two large asynchronous ac systems. Detailed models are used to represent synchronous generators, MMC converters and their controllers. Time-domain simulations of the non-linear model are presented to test the performance the developed model of the hybrid ac/dc power system. A small-signal analysis is used to assess the stability of the overall system.