1. IOS-6.3: Control of experimentally simulated burning state
Proposal to the JE coordination meeting for 2011
IOS-6.3: Control of experimentally simulated burning state
Status: new, resubmitted
Contributors: S. Wolfe (C-MOD), T. Luce (DIII-D), C. Challis (JET), T. Suzuki (JT-60U) Objectives: In burning plasma, pressure and heating power are strongly coupled through α-particle heating. This strong coupling can cause a thermal excursion without burn control in burning plasma. Reliable burn control is essential. This joint experiment focuses on the controllability of transient change into a burning state in the ITER standard operation scenario condition. Plan 2011: To start real-time control experiment in contributing devices in the ITER standard operation scenario condition. That is, q95~3, Q=10 (Pa=2Pex) and at the timing of transition from L-mode regime to ELMy H-mode regime. External heating power is divided into two groups. One group (Pa) simulates alpha-particle heating through positive feedback control proportional to the neutron emission rate (gain G). The other group (Pex) is used as a control knob on the simulated burning state. Adjusting the gain G, the Q=10 (Pa=2Pex) condition is to be realized. Due to the difference in Ip in participating device, results at different energy confinement time will be obtained, which brings about difference of time scale in the transient change of the burning state. Through comparison between the devices, controllability of ITER is to be discussed.

2. Current Status (preparation is going on C-Mod and DIII-D)
C-Mod: No experiment this year and no schedule on this JE during the next six months. I am hoping to implement some enhancements to our control capability that will enable experiments in the following year.
DIII-D: We have implemented the necessary coding in the DIII-D plasma control system to control some specified heating sources power according to real-time calculations of the ion temperature and density (or total pressure) to simulate alpha heating. We have not tested this in experiment, but hope to begin tests in
JET: Done but Not doing.
JT-60U: Done and will further contribute with available data and analysis