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http://dx.doi.org/10.3795/KSME-B.2016.40.6.397

A Study on the Air Vent Valve of the Hydraulic Servo Actuator for Steam Control of Power Plants  

Lee, Yong Bum (Reliability Assessment Center, Korea Institute of Machinery & Materials)
Lee, Jong Jik (Reliability Assessment Center, Korea Institute of Machinery & Materials)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.40, no.6, 2016 , pp. 397-402 More about this Journal
Abstract
To produce adequate electricity in nuclear and thermal power plants, an optimal amount of steam should be supplied to a generator connected to high- and low-pressure steam turbines. A turbine output control device, which is a special steam valve employed to supply or interrupt the steam to the turbine, is operated using a hydraulic servo actuator. In power plants, the performance of servo actuators is degraded by the air generated from the hydraulic system, or causes frequent failures owing to an increase in the wear of the seal. This is due to the seal being burnt as generated heat using the produced compressed air. Some power plants have exhausted air using a fixed orifice, and thus they encounter power loss due to mass flow exhaust. Failures are generated in hydraulic pumps, electric motors, and valves, which are frequently operated. In this study, we perform modeling and analysis of the load-sensing air-exhaust valves, which can be passed through very fine flow under normal use conditions, and exhaust mass flow air at the beginning stage as with existing fixed orifices. Then, we propose a method to prevent failures due to the compressed air, and to ensure the control accuracy of hydraulic servo actuators.
Keywords
Power Plants; Hydraulic Servo Actuator; Hydraulic Fluid; Air and Gas; Modeling and Simulation;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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