AP alpha I controller for linear systems with nonconstant disturbances
In this paper, the problem of nonconstant disturbances in linear time invariant lumped single-input/single-output unstable minimum phase plants with relative degree one is studied. Exact output regulation is difficult for systems with nonconstant disturbances, we proposed an adaptive-proportional-alpha-integral (APalphaI) controller which can stabilize those disturbed systems. We compare the performance of the proposed controller (APalphaI) with simple adaptive-proportional-integral (SAPI), simple adaptive-proportional-integral-integral (SAPI(2)), and (SAPalpha) controllers by solving the output tracking problem of a step reference. All simulation results indicate that the performance of the APalphaI controller is better than the performance of the other controllers. For illustration, numerical example is presented. (C) 2002 Elsevier Science Ltd. All rights reserved.
disturbance unstable minimum phase plant adaptive-proportional-integral linear time invariant systems output feedback positive high-frequency gain adaptive stabilizer steady state error