Second life for metro vehicles in Great Britain

10 February 2015

Strukton Rolling Stock is to deliver traction and auxiliary systems to Vivarail for the refurbishment of London Underground vehicles. Vivarail has acquired D78 stock to converse them into diesel-electric multiple units, ready to run on the British railways. The D78 stock will be equipped with four new diesel engines for the power supply. Strukton Rolling Stock will deliver two traction and auxiliary systems for each train, one in the front and one in the back of the vehicle. These systems will convert the power to the right voltage for the motors, batteries and auxiliary systems.


Strukton Rolling Stock’s systems are based on state-of-the-art IGBT technology, assuring smooth acceleration and higher travelling comfort for passengers. Each vehicle will be equipped with an IGBT chopper, which will provide for the required motor current. Strukton will integrate the traction system, control electronics and battery charger in one box. The technology is comparable with the system that Strukton Rolling Stock delivered for the Toulouse metro.

Pilot vehicle

The conversion of the first vehicles will be a pilot project for Vivarail. The pilot unit should be finished in the summer of 2015 and will be tested by Vivarail on its own test track. This will be followed by the conversion of up to 75 2- or 3-car units. A possible future option is storage of the braking energy in batteries or super capacitors, enabling the reuse of braking energy for the lighting and other on-board equipment.

From electric to diesel

While many railway vehicles are conversed from diesel-electric to electric, Vivarail is doing exactly the opposite, with the aim to have trains available for the local  lines serving regional centres  in Great Britain. These lines are at present not electrified, and whilst electrification may be planned for the future, there is an urgent need for extra diesel trains  due to the massive growth in rail traffic which has taken place in recent years.

75 ‘new’ trains

Vivarail is a young company of railway specialists, which was especially set up for the refurbishment and upgrading of D78 stock purchased from London Underground. This stock first entered service in 1980, but the Vivarail conversion will effectively produce new trains. A new propulsion system, new control equipment,  new cab structure and new interiors will result in trains to the latest stand, with a up to 75 new trains that can be leased or bought.