Transient stability assessment of the GB transmission system with high penetrations of wind power

The predominant North-South active power flows across the border between Scotland and England are currently limited by stability considerations. With the increasing penetration of variable-speed wind power plants in northern areas of GB, there is a risk that it may be impossible to fully utilise the thermal capacity of the lines and the stability limit may be increasingly eroded. This will affect the operational flexibility, efficiency and security of the system. The study reported in this paper aims to illustrate some of the key impacts on power transfer limits through this North-South corridor in the presence of increasing levels of wind power plants on the GB transmission system. By focussing on the behaviour of a representative reduced test system following a three-phase fault occurring on one of the two double-circuits of the B6 boundary, the impacts on transient stability margins are qualitatively identified. The outputs of the project are intended to provide a basis for further detailed studies on a more realistic network model.