Fusion Science and Technology / Volume 57 / Number 2T / February 2010 / Pages 148-155
Equilibrium and Instabilities / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics
This article summarises the constraints for tokamak operation. The operating space is restricted by several limitations among which the plasma performance and hence the resulting fusion power has to be optimized. Hard limits which lead ultimately to a termination of the discharge and may damage the first wall as well as soft limits resulting in a reduction of the energy content (and the generated fusion power) of the plasma are described. The operational limits can be summarized in two general groups: excessive radiation from the plasma, and violation of global or local MHD stability boundaries.