Bahn 2000: High speed line Mattstetten-Rothrist (NBS)

Using FABEL, ENOTRAC modelled the network area Bern – Olten (NBS Mattstetten – Rothrist, Grauholz, Bern, main line Bern – Zollikofen – Burgdorf – Aarburg – Olten, line upgrade Solothurn – Wanzwil) according to the Bahn 2000 plan and with additional heavy freight trains and considered:

• Dimensioning of the overhead conductor for the NBS, the required bonds,
• Optimised location of the feed points
• Identification of weak points in the existing overhead wiring installations of the main line.
• The investigation of outage scenarios and possible emergency power supply

Calculation of the electromagnetic fields with the EMFCALC tool as required by the Swiss regulation for protection against non-ionising radiation for the overhead conductor installations of the new line Mattstetten – Rothrist and the line extension Derendingen – Inkwil.
Calculation of the magnetic flux density near "places with sensitive use". Graphical representation of the fields and evaluating the compliance with the Swiss regulation. Validation of the measures taken to reduce the magnetic fields. ENOTRAC later updated the calculations based on as-built conductor positions

During the commissioning of the Mattstetten – Rothrist/Derendingen – Inkwil extension, ENOTRAC conducted various measurements including:

• Electromagnetic field at sensitive locations and standard cross profiles
• Current distribution in the overhead and return conductors as well as in the new substation in Wanzwil
• Temperature rise in the overhead wires
• Impedances
• Protection functions and short circuit

The measurements were taken over a distance of 55 km and had to be completed within 5 days. This required extensive and thorough preparation and planning work. ENOTRAC defined the measurements, conducted the entire planning and coordination between various SBB departments and supervisory authorities and conducted the measurements and analysis.

The radio mast near the new line Mattstetten – Rothrist raised concerns about interference with the railway equipment. To assess the situation, measurements were conducted in the radio frequency range. Since the railway equipment can be a source and a victim, measurements were carried out in two phases, both in the communication radio unit and along the railway installations.

In addition to the tests themselves, ENOTRAC was responsible for the preparation, planning, and coordination between the various players (SBB, V+S and measurement technique, montena emc, radio messaging, Federal Department of Defence, armasuisse).