ECRH power injection in TORE SUPRA

The ECRH experiment on TORE SUPRA is designed to inject up to 3 MW of power at 118 GHz, using an antenna consisting of six fixed spherical mirrors and three mobile steering minors. The position of the mobile mirrors can be varied in real time using two stepper motors for each mobile mirror. In addition to controlling the injection angle, the position of the mobile mirrors also affects the polarisation of the injected wave. Accurate formulae to computer in real time, the stepper motor positions required to obtain the desired beam injection angles have been derived. Formulae to determine the effect on the wave polarisation, of the actual mobile mirror positions have also been determined. These formulae have been verified by precise laser measurements and by comparison of power deposition calculations and experimental results. Experiments with different values of polarisation and injection angles have been carried out in the 2001 campaign.