Simulation System for the Wendelstein 7-X Safety Control System

The Wendelstein 7-X (W7-X) safety instrumented system (SIS) ensures personnel safety and investment protection. The development and implementation of the SIS are based on the international safety standard for the process industry sector, IEC 61511. The SIS is based on a distributed and hierarchically organized architecture consisting of a central safety system (cSS) on the top and many local safety systems (lSS). Each technical component or diagnostic system potentially hazardous to staff or the device is equipped with an lSS, which is responsible for the safety of the component. On the other hand, the cSS ensures safety of the W7-X device as a whole and is part of the central control system of W7-X. For every operation phase of the W7-X experiment, hardware and software updates for the SIS are mandatory. New components with additional lSS functionality and additional safety signals have to be integrated. Already established safety functions must be adapted and new safety functions have to be implemented in the cSS. Finally, the safety programs of the central and lSS have to be verified for every development stage and validated against the safety requirement specification. This paper focuses on the application of a model-based simulation system for the whole SIS of W7-X. A brief introduction into the development process of the SIS and its technical realization will be given followed by a description of the design and implementation of the SIS simulation system using the framework SIMIT (Siemens). Finally, the first operational experience of this simulation system for the preparation of the SIS for the upcoming operation phase OP 1.2b of W7-X will be discussed.