DCS系统调节阀流量特性单值数学模型及评估方法

Single-value Mathematical Model and Evaluation Method of Flow Characteristics of Control Valve Based on DCS System

由于进汽阀或本体设备特性变化,DEH配汽函数无法及时匹配进汽阀(组)的非线性特征,导致进汽流量控制精度下降。为适应DCS系统历史趋势图仅支持随时间而变化的折线图显示的特点,依据汽轮机原理,通过定义汽轮机流量特性因子和等效流量,提出两种较为实用的单一数值形式的汽轮机组调节阀流量特性诊断数学模型及评估方法。两种数学模型均可在DCS系统历史趋势中呈现随时间而变化的单一参数的折线趋势图,实现汽轮机组调节阀流量线性度的准确评估和实时预警功能。

Due to the change of the characteristics of the inlet valve or the main equipment,the DEH steam distribution function cannot match the nonlinear characteristics of the inlet valve(group)in time,resulting in a decrease in the control accuracy of the inlet steam flow.In order to adapt to the characteristics that DCS system's historical trend graph only supports the display of broken line graph which changes with time,according to the principle of steam turbine,by defining the flow characteristic factor and the equivalent flow rate of steam turbine,two practical mathematical models and evaluation methods of single numerical form for the diagnosis of flow characteristics of steam turbine unit regulator are put forward.Both models can present the broken line trend diagram of a single parameter changing with time in the historical trend of DCS system to realize the accurate evaluation and real-time warning function of the flow linearity of the turbine control valve.