High Speed 1 power quality

ABB has successfully delivered a major project to design, manufacture, install and commission reactive power compensation solutions on the High Speed 1 route from St Pancras International to the Channel Tunnel at Dover.
While High Speed 1’s nominal line voltage is 25 kV, there were some areas where it dropped. This was found to be due to the level of inductive reactive power demand as a result of the inherent design of the system’s isolation transformers.


Over a period of 26 months, ABB designed and installed 17 units at nine AC/DC compounds along the 68-mile track, each consisting of a capacitor bank rated at 6.4 MVAr (mega volt amperes reactive) and a reactor rated at 27.5 kV and 303.134 mH (milliHenry). The units’ bespoke design was jointly developed at ABB’s centre of expertise in Ludvika, Sweden and Transmission & Distribution (T&D) Infrastructure business unit based in London. The installation has effectively cancelled out the inductive power demand of the transformers, reducing the voltage drop.

During the project, the team designed a terminal cap that fits on the bushing of each capacitor unit. This cap prevents the electrocution of birds landing on the terminals, an approach that is now being rolled out globally on ABB capacitor unit products.

ABB’s Operations Manager for T&D Infrastructure Seamus O’Neill said:

“We were very pleased to work together as a single unit with HS1.Their input went a long way to deliver the project in a collaborative and supportive environment."

ABB has installed reactive power units for HS1