Robust H∞ control for switched nonlinear systems with application to high-level urban traffic control

This paper presents robust switching control strategies for switched nonlinear systems with constraints on the control inputs. First, a model transformation is proposed in a way that the constraint on the continuous control inputs is relaxed. Next, the effect of disturbance is taken into account and the L₂-gain analysis and H_∞ control design problem for switched nonlinear systems are formulated and proved. Furthermore, the obtained control laws are utilized for urban traffic networks modeled on a high-level using macroscopic fundamental diagram representation. The flow transferred between urban regions along with the timing plans for each region are controlled using continuous and switching controllers. The control objective is translated into a stability and disturbance attenuation problem for the urban network represented as a switched nonlinear system. The uncertain trip demands are considered as norm-bounded disturbance inputs. One major advantage of the proposed scheme is that the parameters of the feedback switching law are obtained offline. Hence, real-time control is possible with this scheme. The achieved results show great performance of the proposed approach in handling uncertain demand profiles.