• 作者： Chang, Der-Ming; Yu, Cheng-Ching
• 中文摘要： 根據操作員的經驗,Luyben等人提出了以DB(distillate-bottoms)結構來控制蒸餾塔塔頂和塔底的產品成分。對高純度且低相對揮發度的蒸餾塔,研究結果顯示,DB控制結構比DV控制具更優異的干擾消除特性。本研究擬對DB控制結構作一深入探討:從模式的取得、系統分析、控制器調諧到系統韌性分析。為確保正確的分析結果,stepping方式取得的模式較可靠,再經由轉換可求出DB結構的系統模式。分析結果顯示,DB控制在動態時系統交互作用十分小。也就是,多環路控制器足以勝任。但是控制器參數的調諧十足的影響系統的響應。我們提出一套以SV(singular value)為主的調諧方法。結果顯示以此法調諧出來的DB控制結構不但在正常操作點有良好的控制品質,而且有非常好的韌性(在不同的操作點也能維持品質以及穩定)。
• 英文摘要： The DB (distillate-bottoms) structure was proposed by Luyben and coworkers on the basis of operators experience for the dual composition control of a distillation column. The DB structure, in regard to a relatively low volatibility and high purity column, has been indicated by the results to possess a better disturbance rejection capability over the conventional DV (distillate-vapor boilup) structure. The DB structure has been investigated in this work from the aspects of model validation, interaction and disturbance rejection capabilities, controller tuning and robustness analysis. For the sake of ensuring the correct analysis, the transfer function matrix derived from the stepping technique or analytical expression was better than the model derived from experimental technique, e.g. , ATV (autotune variation). Multiloop SISO controllers have been indicated by the interaction and disturbance rejection analyses to perform as well as the inverse based multivariable controller. The controller tuning also played an important role for the performance of the multiloop SISO controllers under the DB control. A simple procedure was proposed for the controller tuning on the basis of the SV (singular value) analysis. Concerning the frequency ranges of interest, the DB structure was quite robust against non-linearity (as the results of changing operating points). A well-tuned DB structure has been indicated by non-linear simulation results to exhibit a good nominal performance and was robust against changes in operating conditions.
• 中文關鍵字： 控制結構; 蒸餾控制; 交互作用分析; 多變數控制
• 英文關鍵字： Control Structure; Distillation Control; Interaction Analysis; Multivariable Control; Distillate-Bottoms Control (Db Control)