Monmouth, UK A system which avoids blackouts in the electricity distribution industry by 'listening' for early signs of failure has been developed by E2L in Wales. They have produced a portable monitor which can detect the phenomenon known as 'partial discharge' well before a breakdown occurs.
Partial discharge has been identified as a major cause of failure in the electricity distribution industry. It is an electrical discharge which damages high- and medium-voltage contacts (10kV upwards) by causing the air to dissociate into nitrogen and oxygen, and then recombine as nitric acid.
Over time supply equipment corrodes away producing a loss of supply. Partial discharge occurs as a result of ageing, operational stresses and minor imperfections in equipment manufacture, and it becomes more significant with time. Without information on the condition of contacts, electricity companies use routine time-interval maintenance which is both expensive and of indeterminate quality.
E2l have been involved for some time in designing industrial instrumentation, particularly using ultrasonic technologies to detect processes such as mechanical wear, high pressure leaks and electrical insulation breakdown. Applying this knowledge to the phenomenon of partial discharge (PD), it has developed the Ultrascan monitoring instrument for electricity generating and distributing companies, specifically for the management of PD-driven maintenance.
Working with UK-based power distributors (Power systems plcand AWE plc) has proven the ultrasonic solution to be better than other methodologies. The monitor increases both electricity supply integrity and customer satisfaction, and improves maintenance quality and reduces maintenance cost.