SYSTEM AND METHOD FOR ADJUSTING THE POSITION OF A CONTROL MEMBER OF A POWER PLANT

摘要

A system for adjusting the position of a control member of a power plant has a hydraulic fluid operated hydraulic actuator (H) provided with a displaceable member (5) connected to the control member (2), and having operating parameters; a servo valve (10) configured to control the hydraulic actuator (H) by means of the hydraulic fluid, and selectively operable between at least an open position for allowing fluid connection with the hydraulic actuator (H) and a closed position for blocking fluid connection to the hydraulic actuator (H); a by-pass fluid device (20) to drain the hydraulic fluid from the hydraulic actuator (H) in any position of the servo valve (10); and a control device (4) configured to selectively driving the servo valve (10) as a function of an operating parameter of the hydraulic actuator (H) so as to compensate the fluid drain, and keep the operating parameter within a given range about a selected target value.