Abstract: During long-term operation, the control system may be affected by complex working environment, the actuator may be damaged to varying degrees and its performance will be degraded, which will cause the performance of the feedback control system to drop or even not work properly. Therefore, in view of the deterioration of system performance caused by actuator degradation, this paper establishes a degradation model for the actuator that works under combinative action of wear and shock. The working condition of the actuator is incorporated in the controller design, and the method based on the probability distribution of failure time is employed to predict remaining life of the system. By adjusting control constraints and modifying set points on line, a trade-off between system performance and actuator health index is found to delay actuator degradation and extend the life cycle of the control system. Finally, the effectiveness of the proposed method is verified by simulated examples.

Key words: hybridmodel, remaining life, life extension control, actuator