Electro-hydraulic actuator system, hydraulic circuit of electro-hydraulic actuator system, and steam turbine system including same

摘要

An object of the present invention is to provide an electro-hydraulic actuator system having an emergency shut-off circuit that operates stably with a simple configuration. A hydraulic cylinder 24 having a piston 25 to which the valve body is connected, a first seal 24A, and a second seal 24B, and hydraulic oil for supplying hydraulic oil to the first seal 24A or the second seal 24B The pump 21, the servomotor M for driving the hydraulic pump 21, the shuttle valve 11 for maintaining the hydraulic pressure generated by the hydraulic pump 21 and communicating with the downstream, and the shuttle valve 11 A logic valve having a solenoid valve (12) that receives hydraulic pressure through the pilot pressure, a first port that receives pilot pressure from the solenoid valve (12), and a second port that communicates with the first seal (24A) of the hydraulic cylinder (24). (13) is provided, and when the solenoid valve (12) is de-energized, the pyop pressure of the logic valve (13) is released, and the logic valve (13) has hydraulic oil in the first seal (24A) communicating with the second port. is introduced into the second seal 24B, and the valve body is urgently shut off by the return spring 26 .