For the aero-engine high and low rotor speed control loops and pressure ratio control loop

the method of determining the stability region of the proportion-integration (PI) control parameters satisfying the gain margin and phase margin was researched. According to the system stability analytical model in frequency domain

the stability region graphic of system parameters in frequency domain with PI controller considered was established. The optimal objective function was defined in terms of the typical dynamic performance indices and robustness indices

and a set of optimal PI control parameters were found in the obtained stability region of control parameters. This method was applied to controller parameters design of aero-engine for the high and low rotor speed control loops and pressure ratio control loop

and PI controllers under different states were designed. Simulation results demonstrate that the tuning method satisfies performance indices and robustness of closed loop system.