Study on the conversion of the railway network to 25 kV in the province of Bolzano

The Autonomous Province of Bolzano – South Tyrol requires a technical study on the feasibility and costs of converting the energy supply of the railway network. The aim is harmonisation in connection with the construction of the Brenner Base Tunnel, but also the possibility of reducing operational and maintenance costs.

A major challenge lies in the complexity of the project, which is why a partner with the extensive experience and know-how of Enotrac was found for it.

About the project

The Environmental Administration Office of the Autonomous Province of Bolzano – South Tyrol is planning to convert the electrical power supply of the railway network in the Province of Bolzano from 3 kV direct current to 25 kV alternating current (50 Hz). The planned conversion is also connected with the construction of the Brenner Base Tunnel, which will be electrified using alternating current at 25 kV.

The primary objective of the project is to harmonise the railway network of the entire province, although there is also the motive of lower expected operational and maintenance costs. A technical study is to serve as a basis for the Province of Bolzano to present the planned project to the key stakeholders, in particular the infrastructure operator RFI, and to substantiate plans as far as possible.

Quelle: STA/Riller

Output from the simulation: voltage stability along the track

Output aus der Simulation: Schienenpotential entlang der Strecke

Our contribution

Enotrac carried out the technical study for the conversion of the energy supply for the Brenner Railway (Brenner – Salurn), Pustertal Railway (Franzensfeste/Vahrn – Innichen) and Merano Railway (Bolzano – Merano) lines. A feasibility study and a possible concept with budget and schedule planning were developed concurrently. The study shows which measures are necessary and how a changeover is possible with the shortest possible interruption to regular operation.

Due to the complexity of the subjects under investigation, Enotrac divided the study into several sub-studies:

  1. Network simulations with Fabel : functional verification of the system design for 25 kV, dimensioning of the components of the railway power supply for 25 kV.
  1. Grid repercussions on the high-voltage grid: assessment of the asymmetric loads that will be exerted on the Terna high-voltage grid by the new 25 kV substations.
  1. Calculation of electromagnetic fields: verification of compliance with exposure and precautionary installation limits for the protection of the population from electromagnetic radiation at 50 Hz .
  1. Induced voltages in pipelines: development of a basis for identifying the pipelines potentially at risk from the conversion that run parallel to the railway line.
  1. Induced voltages in interlocking cables: assessment of contact voltages and dielectric strength of interlocking cables when used in the 25 kV system.
  1. Testing of geometric interference: definition of measures for compliance with electrical protective distances and protective measures against indirect contact in the 25 kV system.
  1. Planning of the transition phase: development of necessary measures and preconditions as well as a rough time schedule for the conversion of the railway lines.

The key figures

All reports are in two languages: German and Italian
0 km
Length of catenary to be converted to 25 kV

Enotrac was able to provide extensive technical know-how in this challenging project. For example, a multi-line model for complete network simulations was developed for the entire electrical network. In-house development of FABEL made this extraordinary approach possible, which is only carried out by a few experts worldwide.

Enotrac was in close consultation with the client throughout the entire duration of the project, which involved regular, closely scheduled coordination meetings. All reports were bilingual, in Italian (project language) and German.

In the final meeting, the client praised the project as a benchmark study.

Source header image: istock, Fortgens Photography

  • Customer

    Autonome Provinz Bozen-Südtirol

  • Period

    January 2021 – December 2021

  • Location

    South Tyrol, Italy

Our services in the project

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