Impact of Tie-Line Power on Inter-Area Modes With Increased Penetration of Wind Power

This paper studies the impact of displacing conventional synchronous generators with wind turbine generators (WTGs) on the damping of inter-area modes. The impact of tie-line power, which can be beneficial or detrimental with increased wind penetration on the damping of the inter-area mode in a two-area test system, is investigated. It is seen that the inter-area modes are more prone to instability when areas with high wind penetrations export power to remote areas. Furthermore, the performance of supplementary controllers in WTGs (i.e., terminal voltage control and inertia emulation) on the inter-area modes are evaluated. The results show that the controllers can mitigate the possible adverse effects of increased penetration of wind power on the inter-area modes. The results of the studies on the two area system are used to guide a study on a 14-generator model of the Australian grid.