A Method for Identifying Faults during Non-full-phase Power Swing Using Teager Energy Operator

With the increase in the scale of the power grid and the development of new energy, the grid structure is becoming more and more complex, and the possibility of non-full-phase power swing caused by single-phase-trip due to the single-phase grounding faults greatly increased. And the methods for identifying faults during non-full-phase power are needed. An identification method based on the characteristics of sound phase current is proposed here. During the non-full-phase power swing, the amplitude and phase of the sound phase current continuously change without sudden change. When a fault occurs, the amplitude and phase of the faulted phase current have sudden change. Based on this feature, the Teager energy operator is used to amplify and quantify the mutation to form the corresponding criterion. The proposed method is simple in calculation, easy to implement, and fast in response. At the same time, the amplifying mutation of the Teager energy operator enables the proposed method to more reliably identify short-circuit faults during non-full-phase power swing and deblock the protection.