  This paper proposes a data-driven algorithm of locating the source of forced
oscillations and suggests the physical interpretation of the method. By
leveraging the sparsity of the forced oscillation sources along with the
low-rank nature of synchrophasor data, the problem of source localization under
resonance conditions is cast as computing the sparse and low-rank components
using Robust Principal Component Analysis (RPCA), which can be efficiently
solved by the exact Augmented Lagrange Multiplier method. Based on this problem
formulation, an efficient and practically implementable algorithm is proposed
to pinpoint the forced oscillation source during real-time operation.
Furthermore, we provide theoretical insights into the efficacy of the proposed
approach by use of physical model-based analysis, in specific by establishing
the fact that the rank of the resonance component matrix is at most 2. The
effectiveness of the proposed method is validated in the IEEE 68-bus power
system and the WECC 179-bus benchmark system.
