The MAST digital plasma control system

The MAST plasma control system [Proc. 20th SOFT, Marcille 1 (1998) 541]] is being upgraded to a fully digital system, to enable greater flexibility and capability than is practical with the existing analogue control hardware. Emphasis was placed on a design that could be implemented quickly whilst still providing a wide range of control capability and room for expansion. In the 2 years since the last publication [Fusion Eng. Des. 56–57 (2001) 541]], the hardware has been specified, acquired, assembled and installed, whilst the software to support it has been developed from General Atomics’ PCS code [Proc. 19th SOFT, Lisbon, Portugal 1 (1996) 965]. The first closed loop control experiment has successfully demonstrated that the digital control system can be programmed to mimic the response of the analogue control system. Development work is now in progress to extend the capabilities of this system. The first priority is to create a better foundation for building new algorithms via a configuration tool that simplifies the programming task. Then the real-time boundary reconstruction capability will be developed, ultimately incorporating a Grad-Shafranov based [Nucl. Fusion 38 (1998) 1055] equilibrium solution, for more precise control capability.