Low Frequency Resonance Suppression in Servo Systems Based on Generalized Proportional-Integral Observer

Servo systems play an irreplaceable role in traditional industry and high-tech fields, and their performance directly determines the actual performance of industrial equipment such as CNC machine tools and robots. Industrial equipment often uses transmission devices such as shafts, transmissions, and couplings to connect motors and loads. These transmission devices are not ideal rigid bodies and are prone to mechanical resonance, which limits the improvement of dynamic performance of servo systems. Therefore, the suppression of mechanical resonance is very important. This article proposes to use generalized proportional-integral (GPI) observer (GPIO) based linear active disturbance rejection control (LADRC) to suppress low-frequency mechanical resonance, and improves the parameter tuning method of GPIO to make its disturbance observation have real bandwidth. The feasibility of the suppression method is analyzed theoretically, and verified through MATLAB/Simulink simulation and experiments.