Low Voltage Ride Through (LVRT) Constrained Transient Stability Assessment Using Lyapunov Functions Family Method

Abstract: Growing penetration of renewable generation in power systems brings more challenges in transient stability assessment using direct methods. One of the reasons is the inability to assess the risk of instability brought by tripping of a large amount of RGs due to violation of their ride through curves. In this paper, a scalable approach is proposed based on the Lyapunov functions family to estimate the stability region under ride through constraints. An inner polytopic approximation to the feasibility region is proposed to convexify the overall problem. The acquired constrained stability region estimate helps capture trajectories that trigger undesirable tripping of renewable generation. A 2-machine system is used to visualize its effectiveness.