| Abstrakt: |
In the context of fault-tolerant control (FTC), we propose a hybrid fault-tolerant control scheme for single-input single-output systems with piecewise continuous dynamic and partial actuator faults (loss of effectiveness). In a single scheme, features of passive FTC and active FTC are indeed mixed to improve the transient response and recover the acceptable performance after an abrupt fault occurrence in a fault-tolerant control system (FTCS). To speed up the transient response, but without causing chattering problems in the control signal, the tolerable fault value used to design the passive FTC is employed here as the initial condition of an adaptive law based on the Lyapunov approach. We exemplify the efficacy of the proposed method by comparing its results with those of a traditional FTCS which use adaptiveness without the special initial condition. The results obtained with the proposed FTCS are better (faster, without chattering, without oscillation, and stable) than the results of the systems that use adaptive law without the special initial condition. Numerical simulation of a nonlinear dynamical magnetic levitation system model is used to exemplify the use of the concept in cases of tolerable and intolerable faults. |
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