基于神经网络时延预测的航空发动机内模控制器设计

Design of Aero-Engine Internal Model Control System Basedon Neural Network Time-Delay Prediction

针对航空发动机分布式控制系统中时延不确定问题,提出了一种基于神经网络时延预测的航空发动机内模多变量控制设计方法。首先分析了分布式控制架构下网络时延产生的原因及影响因素。然后设计了内模控制器,包括基于神经网络的时延预测模块、内模主控制器模块、执行机构小闭环控制模块以及与发动机起动过程开环控制计划相结合的切换控制模块。在理想和扰动条件下,从理论上分析了基于预测时延的内模控制系统的稳定性能,并对所提控制策略下允许的最大时延进行了说明。最后进行了全数字仿真和硬件在环仿真试验。结果表明,所设计的神经网络时延预测模块具备高精度预测能力,内模控制器的稳态误差不超过0.5%,具有良好的抗干扰能力、并满足实时性要求,具有一定的工程应用价值。

Aiming at the uncertainty of time-delay in aero-engine distributed control system,an internal model multi-variable control system based on neural network time-delay prediction is proposed for the aero-en-gine control.Firstly,the causes and influencing factors of the network-induced time-delay in distributed control system are investigated.Then the internal model controller with time-delay is designed,which includes the delay prediction module based on neural network,the main internal model controller module,the actuator inner-loop control module,and the switching control module that combined with the open-loop control plan for the engine starting process.The system stability performance of internal model control with time-delay prediction is analyzed theoretically under ideal and disturbance conditions,as well as the permitted time-delay is then explained under the proposed control strategy.Finally,the full digital simulation and hardware-in-the-loop tests are carried out.The results show that the designed neural network delay prediction module owns the ability to predict current time-delay in high-precision,and the steady-state error of the internal model controller is less than 0.5%.In ad-dition,the proposed controller has satisfactory anti-interference performance and meets the real-time require-ments,which has the feasibility of engineering application.