Research on Indicators of Early Warning in Low Frequency Oscillation Based on Energy Function Theory

This paper simplified the classical transient energy function based on center of inertia, improved the classical indicators of the stability margin, and put forward the indicator of the stability margin increment The indicator was established on the basis of the tie-line observational section in power system, and the calculation was simple and convenient, not only achieving early warnings of low frequency oscillation under multiple disturbances, but also can be used to judge the seriousness of disturbances. The indicator has the potential of online applications. The simulation on NEW ENGLAND 10 machines and the actual system testified the validation of the method.