Absolute stability theory of feedback interconnections and robust antiwindup control design

Almost all physical plants have nonlinearities, and often control performance can be improved by taking them into account. The most commonly encountered example is actuator saturation, since in practice all actuators have limited operation. Control strategies that take such saturation into account are usually termed antiwindup. It is standard to include antiwindup as a failsafe. It is often the case that driving actuators into saturation can result in better performance than using cautious controllers that do not excite the saturation nonlinearities.This proposal concerns controllers that take into account actuator saturation. It will combine rigorous antiwindup design methods with considerations of robustness and more generally with the absolute stability theory of nonlinear feedback systems. Emphasis will also be placed on transferring the results to concrete applications via hardware benchmarking and industrial collaboration.The work falls into four programmes:* Programme 1, unification of analysis results.* Programme 2, robust antiwindup problem definition and antiwindup synthesis.* Programme 3, system specific design.* Programme 4, hardware benchmarking and industrial application.