Scottish Power (SPPS), which owns SP Manweb plc in the United Kingdom and PacifiCorp in the United States, has reached an agreement with U.K. regulator OFGEM to bring automatic post fault restoration to its urban and rural network. This will involve, in the first phase, some 300+ schemes operating out of their primary substations, bringing remote control and automation to approximately 1000 secondary remote switching sites.

For the last four years, SPPS has been working with RADIUS UK Ltd. (Cheshire, England), a manufacturer and supplier of remote control and automation systems, to bring pockets of automation to its rural network. However, following the last regulatory price review, SPSS identified a need for a large-scale approach to post fault restoration on its underground and overhead networks.

RADIUS was awarded this contract and has designed a system tailored to suit SPPS's business needs. Each automation scheme is centered around a primary substation with serial connection back to SPPS's Network Management (NetMan) System, using customer specific protocols. SPPS required each automation routine to run independent of its main supervisory control and data acquisition (SCADA) host, since communication to this could not be relied upon in severe storm situations, nor would it support the algorithms or the additional traffic. However, the SCADA host has complete visibility and control of the schemes.

SPPS also wants the option to have independent control of the network from its primaries via a simple operators panel. This would allow a lineman to switch remote control of the secondary plant to these panels in the event of a storm, when the telecontrol department would either be offline or too busy.

Furthermore, SPPS wanted flexible automation routines so that if an additional plant was added or the network changed, the routines could accommodate the changes without having to download new programs or to adapt existing ones.

In addition, the automation routines had to be flexible so that the secondary sites could be a mixture of reclosers, sectionalizers, aerial switches, ground switches and circuit breakers.

The communications method chosen was RADIUS's digital radio in the VHF spectrum. Because of the multirepeating capabilities of the radio, SPPS has not had to put in any costly radio base stations to achieve the coverage. RADIUS also has implemented a main and stand-by communication paths to provide redundancy in the communications infrastructure. Therefore, if a key repeating secondary node is lost, the outlying sites have a second site they can relay communications through, albeit at a slightly poor fade margin.
Circle 203 on Reader Service Card or visit freeproductinfo.net/tdw