Re: TGV record attempt live on BBC News 24 now

On 5 Apr, 09:26, "Boltar" <boltar2...@xxxxxxxxxxx> wrote:

Do they often raise the voltage?

The transformers at the feeder stations will have a number of tapping
points at the ends of the HV windings connected to the power grid and
these are adjusted on commissioning to give 25 Kv at the catenary at
rated load. They are needed to cater for the voltage available from
the grid in the particular locations. They would be left alone unless
conditions changed, or the line was to be used for special purposes
such as test runs.

What is the maximum voltage normal TGV trains can handle?

Well, 31 kV isn't too much, clearly. Obviously when no train is
drawing power the voltage at the catenary will rise above the 25 KV
figure anyway, even in normal circumstances. There is going to be a
difference between on load and off load voltage. I believe 20%
difference is not uncommon. During transformer testing I have read of
42 KV being applied to test insulation.





.

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