This PhD project investigates the modelling and analysis of an AC-DC system with
synchronous and asynchronous generation (wind farms). The GB network is undergoing major changes including the installation of large amounts of wind generation. Wind farm developments further offshore will be connected via DC connections, such as the eastern link. The first two chapters of the thesis will provide an outline of these changes to the GB system, and the impact of those changes on the frequency response capability of the GB system. In continuation the thesis will engage in modelling details of an AC system with integration of DC technology and wind. The modelling aim is a comprehensive grid representation in a multi-machine small signal stability framework. The inclusion of multi-terminal voltage source converter HVDC links adds further complexities giving rise to difficult research issues. First the solution of an ACDC power flow is described. This solution is then used for the initialization of a dynamic model of the GB network. This model includes the eastern link (represented by a six voltage source converter multiterminal DC grid) and three offshore wind farms (representing Doggerbank, Hornsea and East Anglia ONE). The modelling and results of this simulation will be discussed in detail. The impact of increased wind integration into the GB system is further discussed with respect to the wind farm inertial response capability. An important factor for the inertial response capability is the wake effect. The wake effect describes a reduction in wind speed throughout a wind farm, caused by upstream wind turbines. The reduced wind speed at downstream turbines impacts the inertial response that can be expected from the wind farm. The thesis will conclude by summarising how the inclusion of more wind and HVDC technology impacts on the GB system and the modelling required.