摘要
针对超临界直流锅炉在变负荷运行过程中被控对象参数不断发生变化的特点,将超临界直流锅炉看做具有不确定性的非线性系统,并根据部分分散控制方法对某600MW超临界机组简化模型进行了分析,充分论证了燃料量对中间点温度的动态特性单独建模的合理性.以超临界直流锅炉燃料量变化对水冷壁出口温度的影响为研究对象,进行动态机理分析并建立动态模型,通过计算在3个典型工况点处的传递函数,确定其不确定性模型的参数变化范围.将定量反馈理论应用到煤水比控制中,结合给定的设计性能指标计算出煤水比控制系统的反馈控制器和前置滤波器的参数.结果表明:锅炉中间点温度在不同负荷下都能较快地高精度跟踪给定信号,有较强的鲁棒性,控制性能良好且易于实现.
Supercritical once-through boiler can be regarded as an uncertain nonlinear system, due to con- stant changes of its parameters under the condition of variable load operation. A simplified model for con- trol of 600 MW supercritical unit was analyzed with the method of partially decentralized control, and the rationality of separate modeling based on the effects of dynamic characteristics of fuel quantity on the inter- mediate point temperature was substantially demonstrated. By taking the effect of fuel flow change on out- let temperature of water wall as the object of study, the dynamic mechanism was analyzed and a dynamic model was established, and the variation range of the model with uncertainties was determined through calculation of transfer function under three typical working conditions. Parameters of feedback controller and pre-filter in fuel-water ratio control system were calculated by applying quantitative feedback theory to the fuel-water ratio control, and in combination with the given design performance index. Results showthat the intermediate point temperature of boiler can track given signals rapidly with high accuracy under various loads. The system is featured by strong robustness, good control performance and facile applica tion.
出处
《动力工程学报》
CAS
CSCD
北大核心
2013年第12期947-954,共8页
Journal of Chinese Society of Power Engineering
基金
河北省教育厅2012科研基金资助项目(Z2012011)
关键词
超临界直流锅炉
煤水比
变负荷运行
定量反馈理论
鲁棒性
supercritical once-through boiler
fuel-water ratio
variable load operation
quantitative feedback theory （QFT）
robustness
