田湾三期除氧器水位控制逻辑创新控制方法

Innovative Control Method of Water Level Control Logic of Tianwan Phase III Deaerator

江苏核电5、6号机组除氧器液位由并联的、流量特效不一致的两个调节阀控制,一般情况下,机组负荷低、给水需求较小时,由通流较小的阀门控制除氧器液位,机组负荷高、给水需求较大时,由通流大的阀门单独控制除氧器液位或大小阀门共同控制除氧器液位。初始设计下,阀门手操器、总手操器、PI调节器等环节均缺少无扰跟踪逻辑,不能实现手自动的无扰切换。工程师们通过设置多种模式下的指令函数,并创造性地利用各种控制模式下指令函数的反函数,巧妙设计跟踪、闭环的时间顺序,实现了各种模式下的手自动无扰切换。同时,利用调节器输出范围限制的方法使一套调节参数能够适用不同流量特效的阀门。

There are two control valves for the deaerator liquid level of Unit 5 and 6 of Jiangsu Nuclear Power Plant,which are parallel and have inconsistent flow special effects.Generally,when the unit load is low and the water supply demand is small,the deaerator liquid level is controlled by valves with small flow.When the unit load is high and the water supply demand is large,the deaerator liquid level is controlled by valves with large flow separately or by valves with large and small flow collectively.In the initial design,the valve hand operator,master hand operator,PI regulator and other links lack the disturbance-free tracking logic,which can not realize the automatic disturbance-free switch of the hand.By setting command functions in various modes and creatively utilizing the inverse functions of command functions in various control modes,engineers ingeniously design the time sequence of tracking and closed loop,thus realizing manual automatic and interference-free switching in various modes.At the same time,a set of adjusting parameters can be applied to valves with different flow characteristics by means of adjuster output range limitation.