基于主汽压动态特性的机组协调预测控制研究

Research on predictive coordinated control strategy based on main steam dynamic characteristics

针对火电机组协调控制时存在主蒸汽压力(以下简称主汽压)波动大的问题,研究了一种基于主汽压预测的机组协调控制策略,并将其应用在330 MW机组上。建立了火电机组的主汽压模型,根据330 MW机组数据确定了模型参数,并对模型进行了验证。将该模型用于预测机组主汽压,可由当前负荷指令和燃烧指令预测出主汽压变化趋势。预测主汽压与当前主汽压间的差值可反映入炉燃料量的未来需求,在协调控制策略中用该差值动态修正锅炉侧的入炉燃料量,以克服锅炉惯性,减少主汽压波动。实际运行结果表明:采用该控制策略后,其主汽压波动小于原控制策略,同时机组负荷波动也减小。

There are great fluctuations on main steam pressure of thermal power units in coordinated control.A coordinated control strategy based on main steam pressure prediction is researched and applied to a 330 MW unit.Based on data of the 330 MW unit,parameters of the derived main steam pressure model is determined and the model is verified.Taking the main steam pressure model as prediction model,the trend of main steam pressure can be predicted based on current load instruction and combustion instruction.As the deviation between predictive main steam pressure and the current one is the energy of coal as fire in need,the deviation is employed to correct the energy of coal as fire taking coordinated control strategy,in order to overcome the inertia of furnaces and reduce main steam pressure fluctuations.The practical operation shows that the control strategy can decreases the fluctuation of main steam pressure and load.