H2/H∞ networked control for high-speed train with parameter uncertainty and data transmission time-varying delay

This note concerns speed control for high-speed trains with process time-varying delays. Due to uncertain variations of aerodynamic resistance, train mass, resistance and stiffness of the couplers, the parameter uncertainties and stochastic process disturbances are con- sidered in the multi-ceil model of the train. Meanwhile, because traction/braking forces are simultaneously influenced by both the realtime states and the past states, the process time-varying delays are also involved in the model. For achieving the stability of the system, a networked control law is proposed wherein the data transmission time-varying delays are permitted as well. Since two groups of inter-independent time-delays are simultaneously in the closed-loop systems, a Lyapunov-Krasovskii functional (LKF) is designed and the controller design method is furthermore presented. By the proposed method, not only the almost sure mean square exponential stability (ASMSES) of the closed-loop systems can be guaranteed, but also a pre-given H
2
/H
∞
index level can be achieved. More significantly, the convergence rate of overall system is also pre-specifiable. In the numerical simulation, the networked speed control method is applied to a CRH380A train. The numerical data shows effectiveness and robustness of the proposed method.