Special network switching method and equipment with synchronous digital hierarchy (SDH) network accurate clock synchronization function

Abstract

The invention discloses a special network switching method with a synchronous digital hierarchy (SDH) network accurate clock synchronization function. A master clock in a master substation of a power grid transmits a network clock synchronization message consistent with an institute of electrical and electronic engineers (IEEE)-1588 protocol, and the network clock synchronization message is transmitted to each satellite substation through an Ethernet over SDH (EOS) switch. In each satellite substation, an SDH over Ethernet switch converts the network clock synchronization message into a transmission message consistent with an Ethernet protocol, wherein the switch comprises an internal central processing unit (CPU) and a layer-3 network switching chip, and realizes the data exchange of the Ethernet, and the configuration (selection of adoption of an EOS chip) of each data exchange interface of the Ethernet realizes EOS switching. A data interface of the network switching chip is a reduced gigabit media independent interface (RGMII), and an output interface of the EOS chip is a serializer / deserializer (Serees) interface. A field programmable gate array (FPGA) receives data from the RGMII and the Serdes interface to realize the 1-microsecond accurate clock synchronization.

Description

technical field [0001] The invention belongs to the field of data exchange, and relates to a dedicated network exchange method and equipment with an SDH network precise time synchronization function. The invention is applied in the precise synchronous time synchronization of a power system network. Background technique [0002] With the development of communication technology and the demand of smart grid development, wide-area protection has gradually developed, but the problem that must be solved in wide-area protection is real-time data transmission and precise time synchronization among scattered substations. At present, the data link channel between most substations is the SDH network, which is used for data transmission such as daily dispatching data transmission, image monitoring transmission, operation maintenance management, etc. of the power system. Due to the long distance and wide distribution between substations, it is difficult to re-lay real-time data channels ...

AI Technical Summary

Problems solved by technology

That is, the conversion of Ethernet data into SDH channel data can be realized from the perspective of transmission, but the delay and delay jitter brought about in this conversion process have not been calculated by all EOS devices, and even if calculated, it is impossible Difficult to add to the network accurate time synchronization message

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