Active Disturbance Rejection Controller with Variable Control Gain for Aero-Engine

The working environment for aero-engine is highly demanding, and stringent performance standards must be met. Consequently, a robust active disturbance rejection controller is essential for effective control. However, several issues are associated with the classical active disturbance rejection control technique used in aero engines. These issues include:(1) The system control gain changes with the operating conditions, making the parameter b
0
difficult to tune; (2) Gain of extended state observer is too high due to high-frequency components in the unmodeled dynamics. Therefore, an improved active disturbance rejection control technique with variable control gain is proposed in this paper. Firstly, for the aero-engine speed model, the Gram– Schmidt algorithm is used to identify the control gain offline under various operating conditions. Secondly, by incorporating the concept of gain scheduling, the switching of parameter b
0
is implemented, and the unmodeled dynamics identification value f̂(k) is calculated and used to compensate for improving the classical active disturbance rejection controller. Lastly, a complete simulation experiment was conducted. The simulation results indicate that the proposed method is effective in regulating the aero-engine working process during the transition state, which can quickly tune the parameter b
0
and effectively reduce the bandwidth of the observer under the premise of ensuring the performance.