Active Vibration Control of Rotating Machinery With a Hybrid Piezo-Hydraulic Actuator System

An integrated, compact piezo-hydraulic actuator system for active vibration was designed and developed with a primary application for gas turbine aircraft engines. Copper tube was chosen as the transmission line material for ease of assembly. Liquid plastic which meets incompressibility and low viscosity requirements was adjusted to provide optimal actuator performance. Variants of the liquid plastic have been prepared with desired properties between −40°F and 400° F. The effectiveness of this hybrid actuator for active vibration control (AVC) was demonstrated for suppressing critical speed vibration through two critical speeds for various levels of intentionally placed imbalance. A high accuracy closed loop simulation which combines both finite element and state space methods was applied for the closed loop unbalance response simulation with/without AVC. Good correlation between the simulation and test results was achieved.