The study on the dynamic capability of an electro-hydrostatic actuator to drive a large inertia load

The dynamic capability of an Electro-Hydrostatic Actuator(EHA) to drive a heavy load with a large inertia was studied by both theoretical simulation and experiments, with a general simplified control model presented to explain the dynamic relations of EHAs and their loads. It shows that, with compact monolithic structural designs for both the actuator and its servo-motor-pump, using a notch filter in the position control and a commercial motor driver, given sinusoidal command inputs of 5% full stroke, an EHA mockup to drive a load having an inertia of 1000 kg.m² can have a sufficiently high bandwidth, i.e., 45° phase lag frequency at 18.5rad/s and -3dB amplitude frequency at 71.2rad/s respectively.