航空发动机零点配置/回路传函恢复方法的改进

Improved zero placement/loop transfer recovery method in aeroengine control systems

关键词:  航空发动机  鲁棒控制  零点配置/回路传函恢复+  Kalman滤波器+  稳定性

Key words:  Aircraft engine  Robust control  ZP/LTR~+  Kalman filter~+  Stability

摘要:

为了对零点配置/回路传函恢复(ZP/LTR)方法无法保证闭环系统稳定性的缺陷进行改进,在设计过程中引入了Kalm an滤波器,通过选取特殊的参数,使Kalm an滤波器回路逼近并取代原目标回路,从而在保留ZP/LTR方法性能的同时,通过保证Kalm an滤波器回路的稳定性保证了最后闭环系统的稳定性。研究还证明了如果按文中方法选取参数,则所得的Kalm an滤波器回路是稳定的,从而最终保证了闭环系统的稳定性。最后的实例验证了所得的结论。

Abstract:

Zero Placement /Loop Transfer Recovery(ZP/LTR) method has better mid-frequency property than LQG/LTR method.But the closed loop stability of ZP/LTR method is not guaranteed.This was a great shortcoming of this method that restricted its application.To overcome this shortcoming,an improvement to the ZP/LTR method was introduced.The key part of this improvement was due to a Kalman Filter introduced.With some specially chosen parameters,the Kalman Filter could approximate and finally be substituted for the target feedback loop(TFL) of the original ZP/LTR method.Therefore,with the Kalman Filter as TFL,the improved ZP/LTR method would have similar performance as the original ZP/LTR method.On the other hand,it was proved that,with the specially chosen parameters,the Kalman Filter(as TFL) was stable.According to the separation principle,the resulted closed-loop system was also stable.This is the stability guarantee of the improved ZP/LTR method.Finally,an example was given in this paper.