A first W7-X experiment program editor

Abstract:The Plasma Control System Simulation Platform (PCSSP) for ITER shall support the analysis and development of methods to be used by the ITER Plasma Control System (PCS) for handling exceptions to optimize pulses and assist in machine protection. PCSSP will permit to investigate physical and technical events, such as component failures, control degradation, operation domain excess, plasma state bifurcation or instabilities, and interlock activity. Serving that purpose, the plasma, actuator, diagnostics and PCS simulation modules in PCSSP will be enhanced to compute nominal and offnormal data. Configured by an event schedule, an Event Generator will orchestrate the activation and manipulate the characteristics of such off-normal computation. In the simulated PCS exceptions will be handled in a Pulse Supervision layer operating on top of the Pulse Continuous Control (PCC) feedback loops. It will monitor events, decide on which exceptions to respond, and compute new control references to modify PCC behavior. We discuss basic concepts for the event generation in PCSSP, and a preliminary architecture for exception handling in PCS, and show how these will be configured with event and pulse schedules.

Section: Eh Use Casesmentioning

confidence: 99%

Event generation and simulation of exception handling with the ITER PCSSP

Raupp

Walker

Ambrosino³

et al. 2014

“…From these considerations, two years ago we started to implement a first prototype editor [4] which resolves and displays the elements of a program into a table-like pattern (fig 2 -the middle part) and provides the possibility to edit the values of high level parameters, check simple parameter limits and transform them to low level parameters. Details of the workflow from parameter editing to persistence have been described in [4].…”

Section: Editor Implementation Approachmentioning

confidence: 99%

A W7-X experiment program editor––A usage driven development

Spring

Lewerentz

Bluhm

et al. 2012

Self Cite

The set-up of experiment programs for the complex fusion device Wendelstein 7-X has to define a multitude of parameters which have to obey large number of rules arising from physics and technical constraints. Since this is hard to automate as long as the dependencies are not known sufficiently, the W7-X CoDaC team decided to implement an editor following a constructive approach: Starting from an established experiment program the user is able to modify parts of it -thus complying the usual workflow of experimenters.Already the very first implementation has been deployed at the W7-X CoDaC prototype, the WEGA stellarator. Driven by agile programming principles the weighting of the requirements has been influenced by the editor usage in the daily experiment routine, thus ensuring clientoriented development steps and short release cycles. At present, a stable program editor implementation with graphical preview, immediate feedback on user actions and instantaneous warnings about incorrect settings is under continuous operation at the CoDaC prototype. It has potential to improve together with growing knowledge about the physical and technical constraints. The experiences gained give certainty that the editor is suitable for future use during the start-up phase and the first years of W7-X operation. The structure of W7-X experiment programsWendelstein 7-X is currently built as a highly complex fusion experiment capable of running long-term discharges. Planning a W7-X experiment means to define a multitude of parameters and their intended sequential change, while observing the physical and technical dependencies and constraints.To assist the user with this complex task, three basic concepts have been introduced by the W7-X CoDaC team: the hierarchical component layout, the time segmentation and the abstraction of high-level parameters [1], [2], [3]. This leads to a structured experiment program representation (Fig 1), reflecting both the arbitrary time slice segmentation and the component hierarchy: each time segment for the W7-X project as a whole consists of a set of component tasks, one for each component (where "components" imply both technical machine components and diagnostics). Consecutive segments may be aggregated to scenarios to structure a program into logical parts and to assist reusing such parts in new programs.

“…JET pulse schedule, W7-X experiment program [6]). ASDEX Upgrade, however, distinguishes between parts of the configuration which have a long life cycle, such as consistent sets of plant system parameters (created by the plant system's responsible officers), or control parameter sets (e.g.…”

Section: Experimental Environment and Configurationmentioning

confidence: 99%

Experiment planning and execution workflow at ASDEX Upgrade

Neu

Buhler

Engelhardt

et al. 2011

We present the current workflow from experiment proposals to the actual execution and evaluation of discharges at the ASDEX Upgrade tokamak. Requests for experiments are solicited from both within the IPP and from external collaborators in the yearly call-for-proposals, checked for feasibility and compliance with the project's research goals and collected in a proposal database. During the campaign shot requests are derived from the proposals and in weekly operation meetings the requests are mapped to a schedule (shotlist). Before the execution of discharges a complete set of configuration data needs to be assembled. After the execution follows the analysis (including the evaluation of the discharge as to its usefulness for the underlying proposal) and logging of the attained parameters in a physics logbook. The paper describes processes, software tools, and information management showing how they ultimately lead to an improved scientific productivity.