Identification of Voltage Stability Critical Locations for Future Large Grids With High Renewable Mix.

There is a lot of interest in the policymakers' plans to have grids run entirely on renewable energy in the upcoming years. As a result of the high renewable penetration, future large interconnected grids (LIGs) become more volatile and difficult to operate. To understand future grids better, the planning studies of future grids must consider a wide range of operating conditions and contingencies. In this paper, we propose a novel future grid planning framework that can simulate a wide range of operating conditions and contingencies while considering future policy and topology changes, production cost models, dynamics, steady state AC power flow, and cascade constraints. Using this proposed framework, we propose an approach to identify voltage stability critical locations in the future grid without assumptions on switching devices and load change trajectories during system collapse, while also considering the cascading/time-series behavior of future LIGs. The proposed future grid planning framework is used to generate 1.485 terabytes of dynamic simulation data for 2028 WECC system containing 4455 scenarios. The proposed voltage stability approach is demonstrated on the 2028 representation of the WECC system, and IEEE 30, 300-bus systems.