Transient stability analysis of integrated ac and dc power systems.
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
This thesis describes the development of accurate models for representing power system converter loads in Transient Stability analysis. An accurate load model is developed for rectifier loads, such as smelters and chlorine plants, in which all modes of rectifier operation are accounted for and the dynamics of the DC load represented. The limitation of representing HVDC links with a Quasi-Steady State model are recognized and an alternative method is developed which uses interactive coordination between a transient converter simulation programme and a multi-machine transient stability programme. The algorithm provides an accurate AC system model for transient converter simulations and an accurate DC system model for transient stability analysis. Case study results are presented which show the limitations of the Quasi-Steady State model and the algorithm is used to examine the possibility of using HVDC links for first swing stability improvement.