A linear-quadratic-integral regulator for local ramp metering in the case of distant downstream bottlenecksA linear-quadratic-integral regulator for local ramp metering in the case of distant downstream bottlenecks Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2021-12-212020enThe research leading to these results has received funding from the European Research Council under the E.U.’s 7th Framework Programme (FP/2007-2013)/ERC Grant Agreement n. [321132], project TRAMAN21.This work develops and investigates the performance of a new control law, specifically a Linear-Quadratic Regulator augmented with integral action (LQI), for the local ramp metering control problem when bottlenecks are located many kilometers (up to 5 km) downstream of the metered on-ramp. LQI makes use of measurements all along the stretch extending from the controllable on-ramp to the bottleneck location, being therefore capable to improve the stability and robustness properties of the control loop, compared to alternative approaches (PI regulators) that employ measurements only from the bottleneck location. Simulation results reveal that: i) the proposed methodology handles efficiently the local ramp metering task in case of very distant downstream bottlenecks; and, ii) LQI is much less sensitive compared to other previously proposed control strategies.http://creativecommons.org/licenses/by/4.0/Transportation Letters1210723-731 Stylianopoulou Evgenia Στυλιανοπουλου Ευγενια Kontorinaki Maria Κοντορινακη Μαρια Papageorgiou Markos Παπαγεωργιου Μαρκος Papamichail Ioannis Παπαμιχαηλ Ιωαννης Taylor and Francis Ramp metering Distant downstream bottlenecks Linear-quadratic-integral regulator