华电技术 ›› 2017, Vol. 39 ›› Issue (7): 48-51.

• 技术交流 • 上一篇    下一篇

超(超)临界机组低负荷时MFT动作原因分析及优化策略

  

  1. 大唐华中电力试验研究所,郑州〓450000
  • 出版日期:2017-07-25 发布日期:2017-08-08

Super (ultra) critical unit low load MFT cause analysis and improvement strategy

  1. Datang Central China Electric Power Test Research Institute, Zhengzhou 450000, China
  • Online:2017-07-25 Published:2017-08-08

摘要:

针对两台超临界机组低负荷变工况运行中由于给水泵再循环阀开启,造成机组给水流量低,触发主燃料跳闸(MFT)信号的非停事件进行分析,设计了阶梯式比例-积分-微分(PID)控制策略:给水泵入口流量较高时,再循环阀由PID自动控制;给水泵入口流量降至保护开启定值时,再循环阀由流量阀位函数综合控制。大大降低了再循环阀对给水流量的影响,提高了机组低负荷运行的安全性。

关键词:

Abstract:

The incident that main fuel trip (MFT) of two units of supercritical units, which was caused by feed pump recirculating valve opened while varying condition operating, was analyzed. A proportionalintegralderivative (PID) control strategy was designed. If feed pump inlet flow rate is higher than protection value, recirculating valve is automatically controlled by PID. If feed pump inlet flow rate is low to protection value, recirculating valve is controlled by valve position function. This significantly reduced the effect of recirculating valve on feed water flow rate, and enhanced the safety of units operating in low load.

Key words: