Özet: |
When a new transit line is to be built, apart from many
other aspects, it is also necessary to study alternatives of traction
power supply system. One aspect to be studied in calculating the
operational cost is the estimated level of electricity cost.
If the line capacity exceeds 22000 pphpd
(Passenger Per Hour Per Direction), i.e. medium sized transport capacity,
train-set configuration will consist of more than 4 vehicles, and headway
time between the trains will get narrower, which results in greater
traction energy demand. Energy loss in a conductor is proportional
to square of current drawn from it. As a result, in theory, doubling
the voltage level reduces the energy losses to one quarter. This
might not be correct due to regenerative braking energy.
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