基于历史数据挖掘和劳斯判据的某火电机组功率振荡机理分析  

Analysis of power oscillation mechanism of a thermal power unit based on historical data mining and Routh-criterion

作　　者：吴鹏 柏毅辉 李前敏 张锐锋 WU Peng;BAIYihui;LI Qianmin;ZHANG Ruifeng(Electric Power Research Institute of Guizhou Power Grid Co.,Ltd.,Guiyang 550002 Guizhou,Chin)

机构地区：[1]贵州电网有限责任公司电力科学研究院,贵州贵阳550002

出　　处：《电力大数据》2018年第7期46-52,共7页Power Systems and Big Data

摘　　要：当汽轮机阀门流量特性恶化时,会引起发电机组功率振荡,进而可能引发电网低频振荡。本文以发生过功率振荡的某660 MW超临界机组为例,通过数据挖掘和劳斯稳定判据原理,挖掘机组历史数据得到实际阀门流量特性,同时建立有功调节系统综合模型,定性、定量地分析汽轮机阀门流量特性对系统稳定性的影响,计算得到使系统失稳的阀门流量特性曲线曲率(k)的临界值为3.3438,当k大于临界值时,系统将失稳。同时,通过数据挖掘分析发现机组在92.7%~96.6%综合阀位指令段的阀门流量特性恶化严重,k值最大达到了7.771,远大于临界值,这是导致机组在该指令区间内发生多次功率振荡事件的根本原因。本文的分析方法对今后类似功率振荡事件的分析诊断,有一定的借鉴作用。When the discharge characteristics of turbine valves go to worsen,the power oscillation will be induced,and then the low-frequency oscillation in power grid may be induced.In this paper,a certain 660 MW supercritical unit where power oscillations occurred is taken as an example.Through data mining and Routh-criterion stability criterion principle,the valves discharge characteristics are got by mining the historical data,At the same time,a comprehensive model of active power regulation system is set up,and the influence of turbine valves discharge characteristics on the system stability is qualitatively and quantitatively researched.The critical value of the curvature of the valve discharge characteristic curve（k）for the system instability is calculated to be 3.3438.The system will be unstable over this value.Through data mining analysis,turbine valves discharge characteristics of this unit are found to have worsened among 92.7%-96.6% of total valve position instruction,where the maximum k value is 7.771,far greater than the critical value,which is the reason why several power oscillations occurred in this range of total valve position instruction.That can be used for reference in the analysis on similar power oscillation events in the future.

关 键 词：功率振荡 汽轮机阀门流量特性 数据挖掘 劳斯判据 

分 类 号：TK26[动力工程及工程热物理—动力机械及工程]