Communication Protocol
PRS-7367 317
9.4.2.5 GOOSE
GOOSE service is used to transmit fast messages, such as trip signal and switch position.
The GOOSE service adopts the peer-to-peer transmission, and is classified as GOOSE sending
and GOOSE receiving.
9.4.2.6 GOOSE sending mechanism
GOCB is automatically enabled when the unit is powered on. When all status of the unit is
determined, it performs sending according to the data set shifting mode, to quickly send the initial
status of the own GOOSE information;
The time interval for immediate re-sending after shifting of GOOSE message is the MinTime
parameter (i.e. T1). The “timeAllowedtoLive” parameter in GOOSE message is 2 times of the
“MaxTime” configuration parameter (i.e. 2T0);
9.4.2.7 GOOSE receiving mechanism
The GOOSE receiving buffer zone of the unit receives the new GOOSE messages, after a strict
check of the relevant parameters of GOOSE messages. The receiving side first compares whether
the StNum (status number) of the newly received frame and that in the GOOSE message of the
previous frame are equal. If the StNum of the two frames of GOOSE messages are equal, the
SqNum (sequence number) of the two frames of GOOSE messages are compared. If the SqNum
of the newly received GOOSE frame is bigger than the SqNum of the previous frame, this GOOSE
message is discarded, otherwise the data of the receiving side is updated. If the two GOOSE
messages have different StNums, the data of the receiving side are updated;
When receiving GOOSE messages, the PRS-7000 series unit strictly checks if parameters such
as AppID, GOID, GOCBRef, DataSet and ConfRev are matching.
In receiving GOOSE messages, it will take into account cases of communication interruption of
fault with issuing unit. When the GOOSE communication is interrupted or the configured versions
are not identical, the received GOOSE message should maintain the status before interruption.
9.4.3 Data set and control block
PRS-7000 series devices support real-time sending of data. The data objects requiring real-time
monitoring are configured into data set, and the data set is associated to report control and GoCB,
so that the change information of monitored objects can be sent in real-time to the SCADA via the
report service and GOOSE.
9.4.3.1 Data set
PRS-7000 series devices usually configure data sets in advance in the ICD document, such as
protection event, protection digital input and protection measurement. The SCT (system
configuration tool) can also add, delete and modify data set configuration according to the needs
of existing actual projects.
To Next Page
Loading...
Need help?
General