{"id":621,"date":"2016-12-08T11:22:51","date_gmt":"2016-12-08T10:22:51","guid":{"rendered":"https:\/\/www.prover.com\/?post_type=avada_portfolio&p=621"},"modified":"2025-01-13T09:49:51","modified_gmt":"2025-01-13T08:49:51","slug":"karlberg-stockholm","status":"publish","type":"avada_portfolio","link":"https:\/\/www.prover.com\/references\/karlberg-stockholm\/","title":{"rendered":"Formal verification for Stockholm Central"},"content":{"rendered":"

\"Purpose\"<\/span><\/div><\/div><\/div>
Purpose<\/h5><\/div><\/div><\/div><\/div>

Perform formal safety verification to identify and eliminate errors, to improve the safety assessment process compared to only using traditional, manual review. In particular to find single hardware faults that can cause safety issues.<\/p>\n<\/div><\/div><\/div>

\"Client\"<\/span><\/div><\/div><\/div>
Client<\/h5><\/div><\/div><\/div><\/div>

Trafikverket (The Swedish Transport Administration)<\/span><\/p>\n<\/div><\/div><\/div>

\"Signaling<\/span><\/div><\/div><\/div>
Signaling system<\/h5><\/div><\/div><\/div><\/div>

Relay-based interlocking system for mainline railway network, just north of Stockholm Central.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

Formal Verification to Improve Safety Assessment Process<\/h2><\/div><\/div><\/div>
<\/div><\/div>

Stockholm Central and adjacent interlocking systems are based on electro-mechanical relay technology. Trafikverket requires that the changes made to these interlocking systems are verified using formal verification (\u201cmaskingranskning\u201d), as these are among the most complex interlocking systems installed in Sweden, and too complex to be verified using traditional methods. Several major changes are made to these systems, to increase traffic capacity through downtown Stockholm.
\nIn this project during 2014-15, consultancy \u00c5F updated the interlocking system at Karlberg, which connects to the a new 6 km long tunnel with platforms under Stockholm central station as well as to the old part of Stockholm central station. The project verified the safety of the interlocking, including both changed and unchanged parts. It was also ensured that certain design patterns were followed.<\/p>\n<\/div>

\"logo<\/span><\/div><\/div><\/div><\/div>

The formal verification of this relay-based interlocking type is based on:<\/p>\n<\/div>