Hitachi Rail has achieved a significant milestone in its project to modernise the Paris-Lyon high-speed line, successfully completing the first dynamic test of its next-generation digital signalling technology. This paves the way for the system to enter operational service this year.
In collaboration with SNCF Réseau, France's national railway infrastructure manager, Hitachi Rail is replacing the line's outdated signal boxes with its advanced computer-based interlocking systems, known as SEI+.
This €129.3 million project, awarded to Hitachi Rail in December 2019, is part of the broader LGV+ Paris-Lyon contract.

Dynamic tests are a crucial stage in railway project development, simulating real-world operation in a controlled environment. Conducted on an initial section near Paris, the tests confirmed that Hitachi Rail's interlocking system seamlessly interfaced with the test train equipped with ERTMS digital signalling. Commands were successfully transmitted from the remote control centre in Lyon, which is over 500 kilometres away.
"This project marks a first for Hitachi Rail, encompassing essential on-platform and on-site testing within an operational SNCF line," says Bernard Teyssieux, Project Manager at Hitachi Rail. "We deeply appreciate SNCF's trust and collaboration, which have been instrumental in achieving this key milestone."
The project included over 100 people, which included 30 Hitachi Rail engineers who worked on developing the SEI+ technology.
Given the line’s ongoing operation, tests could only be conducted at night, with the on-site testers actively monitoring the SEI+ substations tested. Alongside this, they also assisted SNCF staff as they collected control room staff in data collection.
Hitachi Rail confirmed that product development was nearing completion as well as on-track safety approval. It is hoped that the on-site testing will be completed over the coming months before the commercial launch in autumn 2024.
With product development nearing completion and safety approval on track, the next major milestone is the conclusion of on-site testing before the system's commercial launch in autumn 2024.
Photo: SNCF