Time synchronization method and system for synchronous messages of IEEE1588 (Precision Time Protocol) master-slave clocks of intelligent transformer substation

Abstract

The invention discloses a time synchronization method and a time synchronization system for synchronous messages of IEEE1588 master-slave clocks of an intelligent transformer substation. The method comprises the following steps of: establishing a master clock synchronous message, and sending the timestamp t1 of the sending moment of the message to the clock in a broadcasting manner; recording a receiving moment t2 of the master clock synchronous message; recording an absolute receiving moment TT2 when the master clock synchronous message is received by a slave clock; establishing a slave clock responding message, sending the slave clock responding message to the master clock in a peer-to-peer manner, and recording the timestamp t3 of the sending moment of the message; recording an absolute sending moment TT3 when the slave clock sends the clock responding message; recording an acquiring moment t4 when the master clock acquires the message; calculating a time deviation, and calculating asymmetry errors according to the timestamp t1, the absolute receiving moment TT2, the absolute sending moment TT3 and the acquiring moment t4; and carrying out time correction on the slave clock by the time deviation and the asymmetry errors. According to the time synchronization method and the time synchronization system for synchronous messages of IEEE1588 master-slave clocks of the intelligent transformer substation, the influences of the asymmetry errors can be eliminated, and the time synchronization precision of the master-slave clocks is improved.

Description

technical field [0001] The invention relates to a network synchronous time synchronization technology, in particular to a time synchronization method and system for an IEEE1588 master-slave clock synchronization message of an intelligent substation. Background technique [0002] At present, smart substations are based on networked communication, and its biggest feature and advantage is information sharing. High-precision data synchronization is an important prerequisite and basic attribute for information sharing, and it is becoming the core issue of smart substation technology and has attracted much attention. However, existing smart substation data synchronization usually uses IRIG-B code time synchronization, dedicated optical fiber point-to-point links, and one-way transmission of synchronization signals, which has low reliability and is contrary to the networked information transmission method of smart substations. Therefore, it is necessary to use a more accurate sync...

AI Technical Summary

Problems solved by technology

[0004] (1) Difference in transmission path: The time stamped message may pass through different paths from the master clock to the slave clock and from the slave clock to the master clock. The transmission delay δ experienced by the text 1 and δ 2 It is difficult to be equal;

[0005] (2) Differences in network status: The operating status of the communication network is dynamic, and the processing delays of switches corresponding to different operating states at different times are different, and the operating status is closely related to the load of the network

Therefore, even if the round-trip transmission path is symmetrical and the network status is different, the transmission delay δ 1 and δ 2 It's hard to be equal

[0006] Therefore, due to the difference between the network operating status and the transmission path may cause synchronization asymmetry error, IEEE1588 time synchronization has the inherent defect of network time synchronization uncertainty

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