Digital control system for the TCV tokamak

This paper presents the hardware and software approach to replacing the current analogue linear feedback system on the TCV tokamak with a DSP based system to allow for nonlinear control. After preliminary combination, over 120 control signals are reduced to 32 parameters which enter an array of 32 DSP processors each of which is passed the complete data set. Apart from data transfer and storage, each DSP run its separate control algorithm with a repetition rate up to 20 kHz. A separate DSP board is dedicated to the plasma vertical control which requires a 200 kHz feedback rate. This paper presents the hardware and the software that is being designed to put this control block in the hands of non DSP-expert physics users.