Network Management on the Isles of Scilly

Ben GodfreyWestern Power DistributionInnovation and Low Carbon Networks Engineer01332 827447/07894258687bgodfrey@westernpower.co.uk

The Isles of Scilly

• 40 km off Lands End

• 5 inhabited

• Only these 5 have electricity supplies

• Population approximately 2000 people

• Supplies by a 33kV undersea cable from the mainland

• 11kV submarine cables interconnect and feed the islands

• 64 substations with a mix of overhead and underground network

• Back up diesel generation to secure supplies

Electrical Network

LV monitoring has been installed on the 64 substations supplying customers

Network Management Project

Battery

Broadband over Powerline Modem

Rack-mounts for Radios

RCDs

Heater

Serial acquisition device

Smart Meter

Main Supply& Battery Changeover

AC/DC Converter

Main Fuses

TCP/IP-based network which uses three technologies:

• GE SD4 radios – 400MHz – 19.2kbps• GE Entranet radios – 2.4Ghz – 106kbps• PPC Broadband over Powerline – BPL –

50Mbps

A 150Mbps microwave link connects to the mainland

Communications Backhaul

Typical Radio Sites

Typical BPL Sites

• Trending of individual substation in NMS

• Metered values stored on a central server

• Greater visibility of asset capacity and utilisation

• Enables automation roll-out

• Comparison of communication systems

Benefits

• 2 x 200kVA peak diesel generators have been installed on both St Agnes and Bryer

• FG Wilson P200-2 generators with ComAp InteliGen-NT controllers

• Remote control and additional automation installed

• Star-Star transformers installed to provide HV neutral earth

Generator Installation

Proposed SchemeSt Mary’s Primary

St Agnes – Lower Town

33kV

11kV11kV 415V

Gen Controller

Synch Controller

Synch Signal

Bryer – The Quay

11kV 415V

Gen Controller

Synch Signal

IoS CommsNetwork

Synch ControllerSt Buryan Primary

33kV

11kV

Mainland Comms Network

• Automated blackstart restoration

• Ability to switch over to generator supply and back without short interruptions

• Reduce issues with frequency control on a weakly connected network

• Allow a larger amount of embedded generation without introducing frequency oscillation issues

Key Benefits

Ben GodfreyWestern Power DistributionInnovation and Low Carbon Networks Engineer01332 827447/07894258687bgodfrey@westernpower.co.uk

Thanks for listening