双目标约束下的航空发动机分布式控制系统最优保成本容错控制

Optimal guaranteed cost fault-tolerant control with bi-index constraints for aero-engine distributed control system

针对带参数摄动、Markov时延、数据丢包和外部干扰的航空发动机分布式控制系统,研究了当执行机构发生部分失效故障时的被动容错控制问题,在H∞性能指标和成本性能指标双重约束下设计了最优保成本容错控制器.首先对系统模型中的各不确定参数进行量化描述,并在此基础上建立整个闭环系统的增广模型;其次证明了双目标约束下闭环系统渐进稳定的充分条件,并给出保成本容错控制器的设计方法;基于双目标相容性理论,得到最优保成本容错控制律的求解方法.仿真结果表明最优保成本容错控制器能够在执行机构发生区间内的任一随机故障时保证闭环系统渐进稳定,并具备一定的H∞性能.且当发动机低压转子转速发生1%阶跃变化时,最优保成本容错控制器的主燃油流量和尾喷管临界截面积峰值仅为最优鲁棒H∞容错控制器的16.03%和16.93%.

The passive fault-tolerant control was studied for aero-engine distributed control system with parameter perturbation,Markov time-delay,data dropout and external disturbance when interval random actuator faults occurred.An optimal guaranteed cost faulttolerant controller was designed under double constran of H∞ and cost performance index.At the beginning,uncertain parameters were described quantitatively.Based on the description a closed-loop augmented model was built.Then sufficient conditions for asymptotic stability with bi-index constraints of the augmented system were derived.The design approach of guaranteed cost fault-tolerant controller was proposed.Finally the optimal guaranteed cost fault-tolerant controller was designed based on consistency theory.Simulation results show that the devised controller ensures the closed-loop system asymptotically stable when interval random actuator faults occur,and have a certain H∞ performance.Besides,when low-pressure rotor speed has 1% step change,the maximum main fuel mass flow and throat area in this controller are 16.03% and 16.93%,respectively,of that in optimal robust H∞fault-tol-erant controller.