London Underground Traction Substations

In recent years the London Underground has carried out upgrades of the sub-surface railway which includes new rolling stock, and upgraded substations to supply power to the DC electrification and auxiliary equipment. This involves reinforcing the HV supply lines to the traction substations, increasing the capacity of the substations and changing the operating voltage from 630 VDC to 750 VDC.

Permarail was engaged to carry out the EMC assessments for the upgraded substations.

Permarail is fully conversant with the London Underground requirements in “Electromagnetic Compatibility S1222” and the “Manual of EMC Best Practice” G222. These documents describe the basic framework to ensure that LU meets its obligations of the European Union Directive on EMC, the corresponding UK regulations and applicable LU standards and design rules for best practice.

To assist designers, site visual inspections are made to assess layouts for equipment and cabling, identify the condition of residual equipment and RFI and EMF measurements are made to define the working environment within and outside the substation.

After completion of the works the RFI measurements are compared with the pre-works baseline measurements and with threshold levels in the railway standard BS EN 50121-2. The EMF measurements are compared with ICNIRP reference levels for the protection of workers and the general public

The EMC work is completed by the issue of a compliance statement in the Project File.