Research on Torque Ripple Suppression Method for Electro-Hydrostatic Actuators Based on Harmonic Injection

An Electro-Hydrostatic Actuator (EHA) constitutes a representative servo motor-driven control system, where motor torque ripple stands as a dominant contributor to electromagnetic noise and torsional vibration. Consequently, the suppression of torque ripple represents a pivotal challenge for elevating the operational performance of EHA. This work first investigates the fundamental operating principle of EHA and develops a model to characterize the origins of torque ripple. Building upon this model, a current harmonic analysis is conducted, and a harmonic injection strategy is employed to eliminate harmonic components within the EHA current during operation, thereby refining the EHA current waveform. Simulation outcomes validate the efficacy of the proposed approach, which realizes successful suppression of current harmonics and torque ripple in the EHA system.