DIII-D RESEARCH OPPORTUNITIES FORUM FOR THE 2013 EXPERIMENTAL CAMPAIGN Review | Direct submission with log-in | Request submission without log-in
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Title	316: Model-based control of the current profile and βN for steady state scenarios
Name:	Didier Moreau didier.moreau@cea.fr	Affiliation:	CEA Cadarache
Research Area:	Plasma Control	Presentation time:	Not requested
Co-Author(s):	Michael Walker (GA), Eugenio Schuster (Lehigh University)	ITPA Joint Experiment :	No
Description:	This proposal aims at continuing the development of model-based current profile control in steady state scenarios started in 2011/2012. The goal is to obtain, in a reproducible manner, various requested target q-profiles and βN values for the high-βN phase of the steady state scenarios, by applying the control as early as possible during the ramp-up phase. Magnetic and kinetic profile control algorithms have been implemented in 2011 in the DIII-D PCS. The control actuators are (i) co-current on-axis NBI power, (ii) co-current off-axis NBI power, (iii) counter-current NBI power, (iv) total ECCD power from all gyrotrons in a fixed off-axis current drive configuration, and (v) loop voltage (ohmic coil). Closed-loop experiments were performed successfully in 2011 and 2012 [1] (see background). Now the method must be validated with a broader variation of the target plasma configurations and profiles with the aim of making profile control routinely used as an experimental tool. For this purpose, dedicated non-linear simulations tools are being developed in order to adapt the controller models to changes in the actuators and plasma configuration, and also to choose the optimal controller parameters before each experiment.	ITER IO Urgent Research Task :	No
Experimental Approach/Plan:
Background:
Resource Requirements:	The ongoing current profile control development will require half a day in 2013. Prior to this, some dedicated PCS tests and possibly a few model identification/validation experiments should be conducted in a couple of 2-hour preliminary sessions. NBI at full power will be needed and with waveforms generated in real-time by the PCS, including on axis co-current (30 R/L, 330 R/L), off-axis (150 R/L) and counter-current (210 R/L) beams. Full power ECCD will also be required.
Diagnostic Requirements:	Real-time magnetic measurements, MSE and equilibrium reconstruction including the poloidal flux and the q-profile (RTEFIT2) are essential. Measurements of the density profile, toroidal rotation profile, as well as ion and electron temperature profiles are also required for analysis, not necessarily in real time.
Analysis Requirements:	MATLAB / data stored in mdsplus.
Other Requirements: