Optimal proportional–integral–derivative set-point weighting and tuning rules for proportional set-point weights

In this study, design of low-order feedforward controllers from both reference signal and measurable disturbance for proportional-integral-derivative (PID) controllers is considered. The feedforward controllers from reference are equivalent to the use of a PID controller with set-point weighting. The design problem is formulated as a convex optimisation problem and then solved for a batch of process models. The optimal proportional set-point weights are then used to derive tuning rules that minimise the integrated absolute error. Examples illustrate the usefulness of the proposed method and tuning rules.