Application of wide-area monitoring, protection and control in an electricity distribution network

The application of a wide-area monitoring, protection and control (WAMPAC) system in a 110-kV local area distribution network (six 110 kV substations) is presented. The WAMPAC system consists of a central unit, and a local unit at each of the six 110-kV substations. It integrates the functions of monitoring, protection and control in the system. The protection function includes feeder protection, transformer protection, bus bar protection and CB fail protection. The control function includes synch check, auto-reclose, standby supply restoration, load shedding and generations tripping. The local area distribution network has embedded generations in it. If it is islanded, the system can shed the load or trip excess generations to keep the frequency near 50 Hz to meet the synch check criteria, so that the critical branch (CB) of the standby supply can be auto-closed and grid supply can be restored to the islanded area quickly.