The model reduction method for aero-engine controller based on the optimization output shaping is presented in this paper.Using the LQG/LTR controller as an example

the 8~(th) order LQG/LTR controller is successfully reduced to a 3~(th) order system with this method.First the controller is divided into the integral part and the stable part.A lower order system is used to approach the stable part.With the optimization output shaping method

the lower order system parameters can be calculated using genetic algorithm(GA).Then the step response of them is very close to each other.At last

combining the optimized lower order system with the separated integral part

the reduced order controller can be obtained.Compared with the balanced truncation Schur model reduction method

this method can make the system with lower order and get better dynamic performance.