IEEE1588-based merging unit synchronous timing method adapted to relay protection application

摘要

#$%^&*AU2013101745A420160303.pdf#####ABSTRACT The present invention belongs to the technical field of power transmission and transformation, and particularly relates to a merge unit time synchronization method adapted to relay protection application and based on IEEE1588 synchronization mode in a smart transformation substation. The merge unit switches in three time synchronization states, namely, synchronization lost state, a synchronization following state and a synchronization time keeping state. Based on the hypothesis that a crystal oscillator frequency of the merge unit cannot suddenly change in the present invention, a self clock is compared with a time service clock, and if a time difference exceeds a set range, this time synchronization message is discarded; therefore, a critical problem that a protection device is accidentally closed and locked for a short time in the actual application process of the IEEE1588 is solved. According to sufficient test verification, short-time anomalies of all types of clocking systems can be avoided on the basis that the relay protection system reliability is guaranteed, and the method can be directly applied to a merge unit in an engineering application. - 16-/ cj) NN C:C 0