Plasma shape and position control in highly elongated tokamaks
Plasma shape and position control in elongated tokamaks is analysed, using the TSC code. A new algorithm is presented, which allows the shape evolution of a discharge to be entirely preprogrammed. The algorithm computes poloidal field coil voltages as functions of time, using magnetic measurements made close to the vessel wall. No preprogrammed coil current wave forms are required. By simulating the start-up phase of typical TCV tokamak discharges, it is shown that the actual shape evolution closely follows the preprogrammed one. X-points can be specified at arbitrary positions. Active stabilisation of the dominant vertical mode is achieved by a conventional PD feedback loop. The optimisation of feedback coefficients, the trade-off between shape accuracy and power dissipation in the poloidal field coils, and the computing power requirements to implement the algorithm in a real experiment are discussed.
Bibliographic Reference: Article: Nuclear Fusion, Vol. 30 (1990) No. 10, pp. 2013-2022
Record Number: 199110113 / Last updated on: 1994-12-02
Original language: en
Available languages: en