Disturbance observer-based sliding mode control for consensus tracking of chaotic nonlinear multi-agent systems

Abstract

This paper deals with the finite-time consensus of chaotic MIMO nonlinear heterogeneous multi-agent systems subjected to matched uncertainties and disturbances. This study proposes a consensus protocol utilizing a novel dynamic sliding mode control, ensuring robust performance and chattering attenuation. For this purpose, firstly, a new time-varying nonlinear sliding manifold is introduced that guarantees exponential finite-time stability. Secondly, a novel reaching law is established that ensures fixed reaching time independent of initial conditions. The fixed reaching time enables the specification of the reaching time by considering the problem constraints. Then, a novel terminal disturbance observer is proposed to efficiently estimate the overall effect of uncertainties and disturbances in the finite-time. Finally, an adaptive form of the proposed controller is presented by incorporating the disturbance observer into the proposed sliding mode control. The proposed consensus protocols are applied to a multi-agent system consisting of two well-known chaotic power systems (PMSM and BLDCM). Computer simulations and comparative studies confirm the results of this study in terms of tracking errors and fast convergence.