摘要
针对火电机组空气预热器停运、空气冷却机组背压快速升高、高压加热器解列等恶劣事故工况,研究通过触发快速减负荷(runback,RB)动作,实现机组自动恢复稳定运行。根据各类型RB的特点以及核心问题的动态特性,有针对性地进行方案设计。对空气预热器RB触发后风烟系统的控制策略进行优化,有效减少了风烟系统的波动;对于机组背压快速升高的工况,差异化设计协调快降负荷和高背压RB这2种控制策略;对于高压加热器解列RB,考虑负荷突增及压力升高影响锅炉上水的潜在安全隐患,设计了给水偏置和除氧器上水调门“先增后降”的动作逻辑。在超超临界百万机组中的应用验证结果表明,该控制策略能够在各类型RB动作后,保障机组自动快速地减负荷并安全运行,且机组主要参数控制效果良好。
Aiming at some severe accident conditions such as the shutdown of air preheater of thermal power unit,rising of back pressure of air-cooling unit,quitting of high pressure heater,and so on,the steady operation of the unit can be realized automatically by triggering runback(RB)action.According to the characteristic of each type of RB,the control of core issues has been designed targeted.After the air preheater RB is triggered,the control strategy of the air and gas system is optimized,which effectively reduces the disturbance.For the working condition of the unit with increased back pressure,two control strategies of coordinated fast drop load and high back pressure RB are designed differently.For the RB of quitting of high pressure heater,the hidden dangers caused by sudden increase of load and pressure which may affect the boiler water supply,the action logic of first increase and then decrease for the feed water bias and deaerator water supply valve is designed.This control strategy has been applied in an ultra supercritical 1000 MW unit,which ensures that the unit can automatically reduce load quickly and operate safely during various types of RB actions.Meanwhile,the control effects of the main parameters of the unit are good.
作者
邢智炜
刘磊
尤默
秦天牧
XING Zhiwei;LIU Lei;YOU Mo;QIN Tianmu(North China Electric Power Institute Co.,Ltd.,Beijing 100045,China)
出处
《广东电力》
2022年第7期161-169,共9页
Guangdong Electric Power
基金
华北电力科学研究院自有资金项目(KJZ2020086)。
关键词
火电机组
减负荷
非常规
不同类型
核心控制策略
thermal power unit
runback(RB)
unconventional
different types
core control strategy