A developed dynamic model of a hybrid AC-DC gird based on UK future power system will be presented. The model has been built in RTDS, and it consists of: (1) a four terminals symmetrical bi-polar MTDC grid with five branches and modelled in small time steps (<2.5µs) environment. (2) a reduced dynamic model of the UK power system developed in normal time steps (50µs). The DC grid and AC grid models are connected together using the RTDS dual time step interface technique. The dynamic performance of the hybrid AC-DC grid including the AC frequency response and converter stations response against different AC and DC short-circuit faults is tested, and recommendations on the protection requirements to mitigate such issues will be presented.
Zhou Liu • Delft University of Technology