针对网络时延的发动机PI控制系统稳定性分析和控制器设计

Stability Analysis and Controller Design of Engine PI Control System for Network Time-Delay

针对航空发动机分布式控制系统中的通信时延问题,进行了PI控制系统稳定性及控制设计。基于Nyquist稳定性判据分析比例系数K_(p)的稳定域,进一步采用等效开环传递函数分析积分增益K_(i)的稳定域,获得时延上界依赖型PI控制器参数稳定域。基于参数稳定域设计某涡扇发动机分布式控制系统的时延PI控制器,并进行了数字仿真。结果表明:在时延上界为0.3 s时,基于参数稳定域设计的PI控制器可保证被控系统的稳定性,系统无稳态误差,转速控制系统超调量不超过0.38%;反之,基于控制器参数非稳定域设计的控制器使被控系统的性能显著恶化。

Aiming at the problem of communication time-delay in distributed control system of aeroengine,the stability and control de⁃sign of PI control system were carried out.The stability domain of proportional coefficient K_(p) was analyzed based on Nyquist stability crite⁃rion,and the stability domain of integral gain K_(i) was further analyzed by equivalent open-loop transfer function,and the parameter stability domain of time-delay upper bound dependent PI controller was obtained.A time-delay PI controller for a turbofan engine distributed con⁃trol system was designed based on parameter stability domain and digital simulation was carried out.The results show that the PI controller based on the parameter stability domain can guarantee the stability of the controlled system when the time-delay upper bound is 0.3 s,the system has no steady-state error,and the overshoot of the speed control system is not more than 0.38%.On the other hand,the controller designed based on non-stable domain of controller parameters significantly deteriorates the performance of the controlled system.