2022/03/09 by Tianwei Xia, Kai Sun, Xia, Tianwei +1
Engineering · Physics and Astronomy · #Vibration and Dynamic Analysis #Power System Optimization and Stability #Lightning and Electromagnetic Phenomena
paper · pdf · doi:10.48550/arxiv.2203.04808
The participation factor (PF), as an important modal property for small-signal stability, evaluates the linkage between a state variable and a mode. Applying the normal form theory, a nonlinear PF can be defined to evaluate the participation of a state variable into modal dynamics following a large disturbance, that gives considerations to resonances and nonlinearities up to a desired order. However, existing nonlinear PFs are inconsistent with the conventional linear PF when nonlinear dynamics following a large disturbance attenuate and linear modal dynamics become dominating. This paper proposes a time-variant nonlinear PF by introducing a time decaying factor and the definition of a nonlinear mode. The new PFs consider modes of resonances and their values naturally transition to a linear PF when the system state becomes close to its equilibrium. The case study on a two-area four-generator system shows that the new PF can correctly rank generators by their participations in natural and resonance modes of nonlinear oscillation subject to a large disturbance.