  Inverter-based resources (IBRs) are becoming increasingly prevalent in power
systems. Due to the inherently low inertia of inverters, there is a heightened
risk of disruptive voltage oscillations. A particular challenge in the
operation of grid connected IBRs is the variations in the grid side voltage.
The changes in the grid side voltage introduces nonlinear and time-varying
constriants on the inverter voltages themselves. For an operator, it would be
useful to know the set of active and reactive powers that can be tracked under
these time-varying conditons. This paper introduces an optimization model
designed to assess the achievability of power setpoints within the framework of
constrained static state-feedback power control. Additionally, we present a
Monte Carlo simulation-based method to optimize the set of achievable power
setpoints. The efficacy of the proposed approach is validated through
simulation results.
