Abstract:

A new approach to model discrete networked control systems with both time-varying delay and packet loss is presented for the analysis of robust H_∞ control. Sufficient conditions to asymptotically stabilize the system and satisfy the H-infinity disturbance attenuation γ are derived by free-weighting matrices method and Lyapunov-Krasovskii functional. Compared with existing fixed-weighting matrices method in analyzing networked control systems, the introduction of free-weighting matrices greatly reduces the conservatism. Due to the existence of nonlinear terms in the conditions, cone complementarity linearization algorithm is used to change the case into the problem of nonlinear minimization based on linear matrix inequalities. Using this algorithm to solve the maximum delay and the suboptimal solution of γ is presented. A numerical example is given to illustrate the effectiveness and superiority of the proposed approach.

Key words: automatic control technology, networked control, free-weighting matrices, time-varying delay, packet loss, robust H_∞ control, cone complementarity linearization