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July 2015
Reflections at Richborough

Reflections at Richborough

01 July 2015

Tony Walker - Technical support group

Few would deny that the Richborough power station site has had an interesting history. Located on the mouth of the River Stour near Sandwich in Kent, it was originally home to a 342 MW coal-fired power station that entered service in 1962. The station was converted to burn oil in 1971 and then again in 1989 to burn Orimulsion, a proprietary oil and water emulsion imported from Venezuela. Environmental concerns finally led to the power station closing in 1996.

Final clearance of the site took many years, with the long-redundant cooling towers demolished as recently as 2012. This is, however, far from the end for the Richborough site. It retains its national grid interconnector from its days as a power station and, after the construction of new substation on the site, this interconnector is now being used as the grid link for the offshore Thanet Wind Farm.

There are also ambitious plans for the future, which involve turning the site into a green energy park with the potential to provide up to 1.4 GW of power to the grid, all from renewable resources. In addition, National Grid intends to use part of the Richborough site as the UK shore station for the NEMO project, a proposed 1 GW bi-directional HVDC link with Belgium.

Returning to the present, however, as might be expected from a site with such a rich history in the electrical power sector, it is still home to many underground power cables. Some of these are no longer in service and they therefore provide an ideal test bed for evaluating and demonstrating cable test equipment.

This is exactly what happened when John Harrison of HV3, a leading specialist supplier of testing services to the power industry, contacted Megger to find out about the latest developments in power cable testing using time-domain reflectometry techniques. John was already using a SebaKMT SPG32 surge generator and Teleflex SX time-domain reflectometer (TDR), which he had had for some time, but he wanted to confirm that his instruments were performing as well as when it was new.

Arrangements were made, therefore, for Megger engineer Tony Walker to meet John at the Richborough site so that they could carry out tests on a redundant cable using a brand new Teleflex SX TDR alongside John’s older instrument.  

The measurements made were conclusive – both instruments showed the same cable features at exactly the same distances from the point of connection.

This confirmed that John’s instrument was working well and that he can have total confidence in the results it provides when he is depending on it as one of his most important aids for finding cable faults in operational installations. It also reinforced the message that investing in high quality test equipment is money well spent, as it will give many years of useful and reliable service.

In the last couple of weeks Megger has launched a NEW 2-channel TDR rated at CATIV 600 V. Find out more by clicking here


Tags: cooling, domain, power, reflectometer, Richborough, station, TDR, time, towers