ROBUST BURN CONTROL OF FUSION-REACTORS WITH MODULATION OF REFUELING RATE

An integrated 0-dimensional plasma-control code, ASH, has been develop ed and employed to study the possibility of controlling the burn condi tion of an ITER-type fusion reactor by modulating the refueling rate. A key feature of this study is the incorporation of robust control the ory to allow for modeling uncertainties. A constant gain proportional feedback controller is synthesized; the values of feedback gains are o btained by the H-infinity algorithm. With this control method, modulat ion of the refueling rate alone can potentially stabilize fusion burn with the alpha confinement time tau(alpha) = 11 tau(E), or controller delay tau(delay) = 1.5 tau(E), or D-T recycling ratio 98%. These limi tations are fairly restrictive, indicating that added control, e.g., v ia input power modulation, may be necessary.