循环水泵出口液控蝶阀控制系统优化

循环水系统将冷却水送至高低压凝汽器去冷却汽轮机低压缸排汽,以维持高低压凝汽器的真空,使汽水循环得以继续。循环水泵出口液控蝶阀与循环水泵存在着密切的联系,因此循环水泵出口液控蝶阀的安全性对循环水系统尤为重要。介绍了重锤式液控蝶阀的一般控制方式,分析了循环水泵出口液控蝶阀PLC控制逻辑存在的不足,提出将循环水泵出口液控蝶阀控制引入DCS系统的改造方法。设计了就地控制循环水泵出口液控蝶阀的电气回路,就地控制电源改为220 VAC,解决了信号远距离传送的问题,并提高了电源控制系统的可靠性。

The Control System Technological Transformation of Hydraulic-controlled Butterfly Valves for Circulating Water Pumps

The circulating water system provides cooling water to the high and low pressure steam turbine condenser to cool exhaust steam, so that it can maintain the vacuum of high and low voltage condenser and keep the steam-water cycle continue. There is close contact between the hydraulic-controlled butterfly valves and the circulating water pump,so the safety of hydraulic-controlled butterfly valves is particularly important for the circulating water system. This article describes the general control methods on heavy hammer hydraulic-controlled butterfly valves, and analy- zes its deficiency on controlling PLC logics,then proposes the improvement measures that using DCS system to control the hydraulic-controlled butterfly valves. In this article, it designs an local electric control circuit for the hydraulic- controlled butterfly valves. The local control power had been changed to 220 V AC,it solved the problem of long-dis- tance signal transmission, and improved the reliability of power supply control system.