ausblenden:
Schlagwörter:
22nd Symposium on Fusion Technology (SOFT 2002), Helsinki, 2002-09-09 to 2002-09-13
Zusammenfassung:
ASDEX Upgrade has a large variety of technical systems, heating and fuelling as well as digital
control systems needed for control and optimisation of high performance plasmas. The neutral beam
injection (NBI), electron cyclotron RF (ECRF) and ion cyclotron resonance frequency (ICRF)
heating systems are able to operate in heating as well as in current drive (CD) mode. One of two
NBI systems has recently been redirected to allow more tangential injection to provide larger CD
efficiency. With improved control procedures significant success is achieved in the optimisation of
the conventional H-mode (ITER reference scenario) as well as of `advanced tokamak' scenarios.
The established operational boundaries encounter or exceed those of the reference scenario.
H-modes showing type II ELMs with clearly reduced peak power loads on the target plates are
produced at densities close to the empirical Greenwald density limit. Discharges with nearly full
non-inductively driven plasma current at Greenwald densities are performed. MHD instabilities like
sawteeth and neoclassical tearing modes (NTM) can be tailored and/or completely be stabilised via
electron cyclotron frequency CD at relatively low injection power levels. In addition, several
non-standard feedback control circuits for plasma performance improvements and machine
protection circuits are devised.
