Current measurements by Rogowski coil and voltage measurements by voltage
divider with digital bus where switchgear events and sampled measured values are
shared allows to decouple engineering of measuring hardware from protection
applications. Line to ground currents are always measured in each feeder separately
for the protection purposes of each and every IED. Incoming feeders use resistive
dividers connected to cables and provide voltage measurements for IEDs in
incoming feeders. Outgoing feeders protection schemes may need to use busbar
voltage measurements. one outgoing feeder in section A includes resistive voltage
dividers connected to bus bar system in section A and bus coupler equipped with
resistive voltage dividers connected bus bar system in section B . IEDs in this feeders
beside potential use of measured voltage for their protection schemes publish
voltage sampled measured data to digital communication. All other IEDs either in
section A or B can subscribe this digital voltage measurements for the purpose of
the particular protection scheme.Finally switchgear events are also shared among all
feeders for the purpose of switchgear control, blocking or interlocking logics.
