Transient Stability Analysis Method Based on the Combination of Multiple Indicators

The new power systems have higher requirements for stability control accuracy and speed, and online stability control decision-making based on real-time grid information has become a future development direction. Online stability control optimizes control measures based on real-time stability margins and control objectives, and needs to reliably quantify system stability margins under both stable and unstable scenarios. Aiming at the status quo that the existing indicators are only applicable to stable or unstable scenarios, an online quantification method of stability margin based on the combination of multiple indicators is proposed, which combines the stability indicators that support the fast judgment of stability and the stability indicators that can measure the degree of instability to realize the quantification of stability margin in multiple scenarios. Firstly, the general process of online assessment of transient stability is analyzed. Then, a stability margin online quantification method based on the combination of multiple indicators is designed from the demand of online stability control optimization and decision-making, and the combination of concavity and convexity of phase trajectory and the extended equal-area criterion of homologous data is used as an example to give the application process. Finally, based on the IEEE39 node system, the proposed method is verified to quantify the stability margin when the stability scenario changes, and the analysis of examples shows that the proposed method can give the stability margin in stable and unstable scenarios on the basis of rapid judgment of stability and support the decision-making of stabilization and control.