Motion Control of Large Inertia Loads Using Electrohydrostatic Actuation

Electrohydrostatic actuation is an emerging technology combining the advantages of hydraulic and electric actuation, resulting in energy efficient solutions that appear electric from the outside while hydraulic on the inside. Conventional solutions, however, significantly reduce the natural frequency of the system compared to traditional hydraulic actuators. This may result in considerable loss of performance under feedback control. In this paper, a simple modification for increasing the natural frequency of the system involving a high-pressure accumulator is proposed and investigated. Theoretical analysis demonstrates the potential for considerable improvements using the proposed solution, resulting in higher natural frequencies and improved performance. The results are verified by numerical simulation.