An Improved Tidal Shift Overload Identification Scheme

In order to cope with the problem of misjudgment of the existing power system protection mechanism in identifying the overload caused by current transfer under the consideration of system oscillation, In this study, based on the in-depth analysis of the differences in the dynamic characteristics of the transient processes of power system oscillation, grounded short-circuit faults and overload anomalies, we optimize the design of the fault identification mechanism, and innovatively introduce two new discriminative conditions based on the transient response characteristics into the existing criterion system, and by adding new judgment conditions to the identification scheme. This study systematically compares and analyzes the differences in dynamic response parameters such as amplitude fluctuation rate and phase angle offset under three types of anomalous working conditions, reveals the recognizable characteristics of different anomalous states at the level of amplitude-frequency dynamic characteristics and phase-frequency response characteristics, and establishes a basis for classifying and identifying anomalous states based on the differences in dynamic parameters, the improved scheme proposed in this study significantly improves the fault identification accuracy under complex working conditions, and its effectiveness is verified in time-domain simulation. The numerical simulation experimental results show that the improved overload identification strategy based on the current offset characteristic can accurately distinguish the transient disturbances caused by real overloads and oscillations, and reduce the risk of erroneous operation of the protection under the oscillating conditions of the system. Verification of the technical feasibility and identification accuracy of the improved scheme with the newly introduced criterion