基于Pearson相关性的VAR模型煤电水煤比寻优应用

Optimal Application of VAR Model Based on Pearson Correlation for Coal-electricity Water-coal Ratio

本文为解决350MW燃煤机组在煤质频繁变化情况下水煤比失衡的问题,使用向量自回归(VAR)模型在机组参数波动工况下进行水煤比寻优。通过使用Pearson相关系数分析机组运行参数,确定寻优模型的输入数据,计算VAR模型最优阶数,并建立VAR模型从多个参数的时间序列寻找对应工况下水煤比最优值,同时使用三种不同分析方法确保该最优值的准确性和安全性。实践证明,该方法能有效解决机组由于煤质频繁变化导致锅炉给水策略不适配引发的主蒸汽温度和主蒸汽压力偏差大等问题。

In order to solve the problem of water-to-coal ratio imbalance of 350MW coal-fired units under the condition of frequent changes in coal quality,the vector autoregression(VAR)model is used to optimize the water-to-coal ratio under the condition of unit parameter fluctuations.By using the Pearson correlation coefficient to analyze the operating parameters of the unit,determine the input data of the optimization model,calculate the optimal order of the VAR model,and establish the VAR model to find the optimal value of the water-to-coal ratio in corresponding working conditions from the time series of multiple parameters.Meanwhile,three different analysis methods were used to ensure the accuracy and safety of the optimal value.The practice proves that this method can effectively solve the problems of large deviation of main steam temperature and main steam pressure caused by improper boiler water supply strategy due to frequent changes of coal quality.