Continuous data acquisition with online analysis for the Wendelstein 7-X magnetic diagnostics

The coupling of continuous data acquisition and continuous online analysis keeping up with the acquisition is one of the features the W7-X data acquisition system is designed for. As proof of principle of this concept the magnetic diagnostics have been implemented.The magnetic diagnostics measure time derivatives of the magnetic fluxes and the signals have to be time integrated accordingly. Both measurement and analysis tasks are executed on a single PC based system.The configuration of both hard- and software of the system is presented. Special focuses are the task of software integration of a user supplied online analysis function into the data acquisition system and the incorporation of the complete system into the W7-X segment concept in use by the control system.The complete installation has been tested at the WEGA Stellarator experiment. Because WEGA is capable of continuous steady state plasma operation the practical suitability of the installation for W7-X could be demonstrated successfully.