Core Inlet Guide Vane Actuator

The function of the core inlet guide vane (CIGV) actuator is to mechanically position the inlet guide vanes when commanded by the full authority digital engine control (FADEC). During normal operation, the actuators are modulated according to the FADEC based upon feedback from the master’s linear variable differential transformer (LVDT) signal. Typically, there are two types of CIGV actuators, master and slave. The master is the only one that contains an electro hydraulic servo valve (EHSV) and a LVDT position sensor provides electrical feedback to the FADEC.
Generally, core inlet guide vane (CIGV) actuators are fuel or oil operated. Fuel enters the EHSV cavity of the spoolsleeve area through the “P” inlet port. Electrical signals sent to the dual-coil servo from the full authority digital engine control (FADEC) cause the servo to modulate pressures Control 1 (C1) and Control 2 (C2). C1 and C2 are connected to the two chambers of the actuator piston.