Dstock7080
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The Four Lines Modernisation (4LM) programme has delivered a first for London Underground (LU).
For the first time on our network, the Metropolitan Line, north of Harrow to Amersham, Watford and Chesham, now operate at 750v. Previously it had operated at 630v like the rest of the network.
Senior Project Manager said: Switching on the 750v traction power on this part of the Metropolitan Line is a massive achievement as it will enable us to reduce energy consumption and increase the number of trains per hour to 32 once the new signalling upgrade is complete.
This section of the Metropolitan Line can now operate regenerative braking too. Regenerative braking uses a converter on the train to recycle the energy generated in the braking process so that it can be delivered back to the conductor rail for the next train to use. It will create impressive energy savings, reduce the carbon footprint and maintenance, and increase rolling stock performance.
Lead Project Engineer, said: This is the single biggest event in LU direct current power history in more than 40 years.
To migrate from 630v to 750v, a significant amount of work was completed, including reconfiguring the substation transformers. We also needed to ensure the current online relays, fault detection, tunnel lighting systems, passenger trains and engineering trains were compatible with the higher voltage. The mechanism that tells the train to open its doors was also changed.
These enabling works will allow the Sub Surface Lines (SSL) to increase capacity by a third by 2023, which equates to tens of thousands more customers each hour.
The team will migrate further areas of the SSL track to 750v over the next year.