Active feedback stabilization of the flute instability in a mirror machine using field-aligned coils

TYPEPlasma Physics
Speaker:Assaf Lifshits
Affiliation:Technion
Date:09.02.2012
Time:16:00
Location:Lidow 724
Remark:Masters Seminar
Abstract:

Plasmas confined in mirror machines are unstable even at low b, mainly because of the flute instability.  One possible way to stabilize the plasma is to use active feedback to correct the plasma shape in real-time. An analytical model and a 2-dimentional MHD simulation were used to investigate a system consisting of feedback coils aligned with the magnetic field, immersed in cold plasma around the hot core.  When current is driven through the coils, the plasma moves to conserve magnetic flux.  An algorithm for determining the feedback currents is shown to stabilize the system with zero residual currents.  Also, it is shown that the system's rotation must be taken into account when determining the feedback algorithm.