Abstract:

In many industrial processes, in addition to the online measurements with delay-free and low inaccuracy, there exist delayed measurements accurately obtained by laboratory analysis. The augmented state Kalman filter is employed to estimate the state by incorporating both the delayed and the delay-free measurements. To overcome the model-plant mismatch of the online soft-sensor model built by the delay-free measurements, the model deviation is employed to update the soft-sensor model. To follow the model drift, the model deviation is treated as a state, and it will be estimated when the offline measurements arrive. In the end the proposed method is used to estimate the tray compositions in the linearized nonlinear binary distillation column model and obtains good results.

Key words: time delays, augmented Kalman filter, measurement model, update, distillation column

摘要：

在很多工业过程中,常常可获得两种测量数据,无时滞测量值和含时滞测量值,其中,无时滞测量值直接由传感器在线测得,即时却精度较低,含时滞测量值通过人工实验分析离线得到,精度高却有时滞。引入状态增广卡尔曼滤波法对上述两种数据进行融合以估计当前状态值。考虑到无时滞测量值建立的在线软测量模型存在不可避免的模型不匹配问题,引入模型偏差作为待估计状态,通过离线测量值对其进行估计,从而实现对在线软测量模型的校正。最后将所提方法运用到线性化的非线性二元蒸馏塔模型中估计填料压板各成分浓度,取得了良好效果。

关键词: 时滞, 状态增广卡尔曼滤波, 测量模型, 校正, 蒸馏塔