Dollands Moor AC/DC Changeover System

Dollands Moor AC/DC changeover is an isolation transformer-based changeover scheme at the operational boundaries between Eurotunnel, HS1 and Network Rail infrastructures in Folkstone. This AC/DC changeover is part of a strategic freight link between the UK and Europe.

Permarail has been engaged by Siemens Mobility Limited to provide EMC testing and current and voltage monitoring as part of the project to renew a number of isolation transformers that form part of the changeover system.

Permrail has carried out extensive current and voltage measurements and analysis at multiple locations in and around Dollands Moor in order to determine the characteristics and conduction paths of traction return current in the area, particularly with respect to the interface with Eurotunnel infrastructure.

A staged approach has been adopted, with measurements taken both before and after the commissioning of the transformers, to clearly demonstrate the impact of the works.