Bumpless transfer design of virtual actuator against actuator failure

In this paper, a bumpless transfer strategy of active fault-tolerant control is proposed based on virtual actuator against actuator failure. The traditional technique of virtual actuator is improved for relieving the bump phenomenon when virtual actuator is turned on. Combining with optimal control, a new idea is put forward to suppress this phenomenon in the process of active fault-tolerant control. The necessary and sufficient conditions for the existence of the optimal control are given for two kinds of situations respectively. The hardware-in-the-loop simulations of aero-engines demonstrate that the proposed strategy can effectively lower the impact of bump than the traditional virtual actuator design while recovering the faulty system.