| 摘要 |
<p>The present invention relates to a thermal power generation system, which may include: a steam separator which separates water from steam generated during operation of a boiler; a recirculation valve which controls a water level of the steam separator by recirculating the water generated during operation of the boiler, and is opened/closed by a pneumatic actuator; a trip valve which determines direction of air supplied to the actuator; a filter regulator which supplies filtered external air to the trip valve; an emergency supply tank which stores the air supplied from the filter regulator; a positioner which controls air supply from the emergency supply tank in case the supply of the external air is blocked; and a control device which controls the direction of the air supplied from the emergency supply tank according to the control of the positioner. According to the present invention, the control device of the recirculation valve for the boiler can operate the recirculation valve again by supplying the air through a separate air supply line and a three-directional valve again even though air supply for driving the recirculation valve driven by pneumatic pressure is stopped. Moreover, the system can perform more accurate control by being able to change valve position of the recirculation valve according to a driving condition of the boiler.</p> |
