抄録
Auto-parametric resonance (internal resonance) is regarded as a kind of nonlinear oscillation stemming from the nonlinearity of synchronizing power of generators. The resonance is closely related to power system stability, especially to unstable oscillation phenomena such as “negative damping” and “sustained oscillation”. The authors have already developed a quantitative analysis method and proposed a stability index to estimate power system's viability under resonance condition.
This paper studies a countermeasure to prevent auto-parametric resonance, taking two-mode resonance as a representative example of auto-parametric resonance. First, a control index, which is used as the control objective, is established based on the stability index which has been developed in our earlier works. Then, we examine system parameters governing the control index through sensitivity analysis, and propose an effective method of monitoring and control. The proposed control method can be integrated into the conventional ELD by adding another constraint relating to the resonance to conventional security constraints. The effectiveness of the proposed method is demonstrated using a longitudinal 4-machine system through numerical simulations.
