Abstract :
The CEGB 275/400 kV Supergrid System comprises 209 substations of varying age. In them there are 1668 feeder main protection units and 486 items of signalling equipment. Approximately 65% of these have an unsatisfactory performance, some other kind of limitation or are obsolete. Feeder protection alone provides the CEGB with approximately 25 circuits per year needing to be refurbished, which due to the time taken to carry out the work plus the increased rate of obsolescence of modern equipment, provides a perpetual workload unless times for design, draughting, installation, testing and commissioning of equipment can be considerably reduced. The author describes new techniques for accommodation of protection and control equipment at new and existing substations. The objective is to give reductions in lifetime costs and overall engineering time without loss and if possible, improvements in availability and reliability
