Study on SV packet transmission delay measurement of IEC 61850-9-2 process bus networks in smart substation

Owing to the uncertainty of SV packet transmission delay in switches, the synchronization of network sampling based on the compensation for SV packet transmission delay must rely on an external synchronization system. This letter gives a structure of Ethernet switch based on FPGA aiming to measure the time delay of SV packets transmission, and proposes a method of measuring and storing the time delay using link delay and switch delay time information to extend the IEC 61850-9-2frame.