Extended State Observer-based Synchronization Controller Design for Dual-Redundant Electro-Hydrostatic Actuator of More Electric Aircraft

With the widespread application of more electric aircraft (MEA) technology, electro-hydrostatic actuators (EHA) with high reliability and high power-to-weight ratio have become increasingly prevalent in aviation. Dual-redundant electro-hydrostatic actuator (DR-EHA), which implements redundancy design to achieve higher reliability and fault tolerance, has gradually become the mainstream actuation system. However, due to parameter mismatches between the upper and lower channels of the DR-EHA system, force fighting frequently arises, leading to internal losses and even affecting system stability. This study analyzes the working principle of the DR-EHA system and the causes of force fighting and conducts a parameter sensitivity analysis to identify critical parameters. An extended state observer (ESO) is designed to estimate the internal dynamics and total disturbances of the system in real-time. Based on the ESO estimation results, synchronization controllers are designed to compensate for the force fighting caused by parameter mismatches. Simulation results verify that the proposed ESO-based synchronization controllers significantly reduce the amplitude of force fighting and peak tracking error to below 10% of baseline values, with concurrent moderate enhancement in system response speed.