Traction Power Supply Lötschberg Base Line

For the Lötschberg base tunnel, ENOTRAC was entrusted with a wide range of engineering tasks covering the specification and rating of the 16.7 Hz traction power supply system, as well as that of the 50 Hz supply system. The list of tasks includes:

• Load calculations
• Electrical rating of overhead line systems, cables and network power supply
• Earthing and return current circuitry concept design
• Protection, to limit short circuit currents, supervision of procurement and commissioning of rate-of-rise limiting inductors at the Frutigen substation
• Investigation of network stability
• Non-ionising radiation and other test measurements to validate the design

After the system was installed, ENOTRAC planned, carried out and assessed a wide range of test measurements including:

• Network measurements at the substation converter in Wimmis (in association with emkamatik)
• Network stability measurements (in association with emkamatik)
• Return current and current distribution measurements in the tunnel, on adjoining lines and at the Gampel, Mitholz and Frutigen substations
• Impedance measurements (in association with SBB I-EN)
• Earthing measurements (in association with FKH)
• Temperature measurements on the overhead line conductors
• Demonstration of compliance with TSI Energy
• Measurement of tractive resistance
• EMC measurements
• Test of protection systems during severe short circuits

In addition, expert advice was provided for:

• Earthing
• Switchgear
• Loading gauge