The Stochastic Response Surface Method for Small-Signal Stability Study of Power System With Probabilistic Uncertainties in Correlated Photovoltaic and Loads

This paper explores applications of stochastic response surface method (SRSM) in the small-signal stability analysis of the power system with probabilistic uncertainties in correlated photovoltaic and loads. A detailed model is provided to simulate the dynamics in the PV system. SRSM is presented to approximate the critical damping ratio as a function of independent standard random variables, which are transformed from correlated loads and irradiance by Nataf transformation. Two applications of SRSM are explored, namely, estimating the probability of power system small-signal instability, and providing the emergency control when the system damping is reduced suddenly. The modified two-area four-machine system and IEEE 39-bus 10-machine standard system are used to test SRSM and its applications.