Selection of actuators and sensors for surge control

For surge control in compression systems, a suitable combination of actuators and sensors must be selected. The goal is to identify the combinations for which there exists a controller that locally stabilizes the linearized compression system model and meets additional control objectives. The latter are quantified in terms of a bound on an H-infinity. norm. With this we aim to stay close to the nominal operating point in the face of disturbances, noise, and actuator limitations. The considered selection method is more rigorous than previously found in literature, in the sense that multivariable, dynamic output feedback is the focus and that different performance specifications are handled simultaneously. Though the method was originally developed for linear systems, it can be used for the nonlinear compression system model by linearizing the model on a grid of nominal operating points. Among the proposed actuators and sensors, the close-coupled valve and mass flow sensor are identified as the most promising. The results are sustained by the physics of the problem.