Abstract:

For a class of discrete systems with uncertainties, a gain scheduled integral slidingmode controller is proposed, and the controller’s robust  H_∞ performance is analyzed. The discrete model containing an output error integral term is obtained by states dimension extension. The slidingmode equivalent control law is derived using the property of the ideal slidingmode motion|the gainscheduled compensation control law is derived using the output error integral term. The slidingmode closed loop control system is regarded as a switched system. The relationships between slidingmode control parameters, quadratic stability and robust  H_∞   performance are derived from the theory of switched systems. The linear matrix inequality (LMI) is obtained by dealing with uncertainties and the nonlinear terms. By solving the LMI, the control parameters of the slidingmode meeting the performance requirement is given. The transient performance and disturbance rejection of the controller are analyzed in simulation, and the simulation results show the effectiveness of the proposed method.