Self-Healing Solution for Medium Voltage Feeders on the Isle of Wight

Authors: John Baker, UK, and Mike Meisinger, UK

Introduction


Scottish and Southern selected the Isle of Wight to demonstrate the performance of an automated feeder self-healing solution featuring distributed intelligence. The Isle of Wight was chosen for the pilot project because its network layout is representative of typical SSE layouts. In addition, the area is subject to severe weather conditions that would rigorously test the performance of the self-healing solution, as well as demonstrate the technological advantages of pulseclosing.
The eleven 11-kV feeders, shown in Figure 2, include a mix of underground and overhead feeders. The switching device locations selected for automation were chosen based on cost-justified reliability improvement calculations. These calculations considered the impact on Customer Minutes Lost (CML), total load lost, and customer interruptions, and took into account the following factors:

  • Fault rate
  • Average time to switch
  • Average time to complete a repair, and
  • Underground / overhead splits

 

SSE began installation of the S&C IntelliTeam II® Automatic Restoration System on the Isle of Wight in 2008.  The project included 32 new S&C IntelliRupter® PulseClosers, installed at interim-feeder locations among the 11-kV interconnected circuits. Additionally, S&C Universal Interface Modules (now termed IntelliNode? Interface Modules) were installed in three primary substations associated with the eleven feeders to enable inclusion of the seven feeder breakers as IntelliTeam II sources.
The IntelliRupter PulseClosers replaced existing conventional reclosers and overhead air-break switches. They were furnished with licensed-frequency VHF radios to enable the peer-to-peer communication required by IntelliTeam II.
The three primary substations were also equipped with licensed-frequency VHF radios to enable IntelliTeam II communication with downstream IntelliRupters and also provide a gateway for SCADA monitoring of the automation system and associated devices.

 

 

BeijingSifang June 2016