Generic Object Oriented Substation Events (GOOSE)

Generic Object Oriented Substation Events (GOOSE) is a control model mechanism in which any format of data (status, value) is grouped into a data set and transmitted within a time period of 4 millisecond. The following mechanisms are used to ensure specified transmission speed and reliability.

• GOOSE data is directly embedded into Ethernet data packets and works on publisher-subscriber mechanism on multicast or broadcast MAC addresses.

• GOOSE uses VLAN and priority tagging as per IEEE 802.1Q to have separate virtual network within the same physical network and sets appropriate message priority level.

• Enhanced retransmission mechanisms - The same GOOSE message is retransmitted with varying and increasing re-transmission intervals. A new event occurring within any GOOSE dataset element will result in the existing GOOSE retransmission message being stopped. A state number within the GOOSE protocol identifies whether a GOOSE message is a new message or a retransmitted message.

• GOOSE messages are designed to be brand independent. Some vendors offer intelligent electronic devices (IED) that fully support IEC61850 for a truly interoperable approach within the substation network without requiring vendor specific cables or algorithms.