Electric Backup Hydraulic Actuation

Parker Aerospace designs and manufactures electric backup hydraulic actuation (EBHA) systems. An EBHA is a conventional electrohydraulic servoactuator with a backup EHA in one integrated package. This result in an actuator that is smaller and lighter than dual tandem or two independent simplex actuators. EHBAs allow higher surface availability, or probability loss of function (PLOF), than with a single actuator. A single EBHA can replace dual tandem or multiple simplex actuators primarily used to address loss of the hydraulic system. EBHAs incorporate an independent power source to mitigate potential common mode failures.
EBHAs contain all of the components and function of a conventional electrohydraulic servoactuator. In addition, to provide back-up mode upon loss of the hydraulic system, EBHAs contain of a fixed displacement, high speed, reversible pump driven by a brushless DC electric motor. In electric back-up (EB) mode, the actuator position is controlled by the pump rotation direction and actuator piston velocity is controlled by pump rotational speed.