Nonlinear oscillation description by swing energy sequence of the controlling mode

This paper presents a method to describe nonlinear oscillation of power system. Specifically, this paper uses the con trolling mode which is identified by the extended equal-area criterion (EEAC). The energy of center equal point (CEP) or far end point (FEP) in each swing is used to express the oscillation energy of the controlling mode, so the trend of swing energy variations can be used to show the behavior of the nonlinear oscillation. In addition, the rationality of the method is analyzed and proved by the simulation results.