百万千瓦机组一次风机RB过程汽温控制策略研究

Study on Steam Temperature Control Strategy in Primary Fan RB Process of 1000MW Ultra Supercritical Unit

为减少一次风机故障减负荷(runback,RB)过程中蒸汽温度的波动范围,针对百万千万超超临界机组,对影响超超临界机组RB过程汽温波动的主要因素进行了研究,分析了燃水比、过剩空气系数等影响汽温波动的因素,阐述了机组正常运行时燃料、给水、总风量的调节控制关系,提出了RB过程中的燃料量、给水流量和总风量的控制关系及有效的RB过程汽温控制策略,给出了一次风机RB过程主汽温度、再热汽温度、机组负荷、主汽压力等机组参数的变化结果。大唐潮州电厂4号机组应用及试验结果表明,本文提出的RB控制策略对过热汽温、汽压等参数控制效果良好,对同类机组RB过程的实施具有重要的参考价值。

In order to decrease the fluctuation of steam temperature during primary fan RUBACK（RB） process of 1000MW ultra supercritical unit,the influence factors,the excess air coefficient and the ratio of fuel and feed water were studied and analyzed in detail.The control relationship of fuel,feed water and air input during normal operation was discussed and the effective temperature control strategy about these variables during RB process was proposed.Variation results of main steam temperature,reheat steam temperature,unit load and main steam pressure were given.The application results of improving control strategy in Chaozhou power plant show that the proposed strategy is effective for steam temperature and pressure control and is valuable to RB experiments in similar power plant units.