Optimal Learning Control Combined with Quality Inferential Control for Batch and Semi-batch Processes

  • Chin, In-Sik (Department of Chemical Engineering, Sogang University) ;
  • Lee, Kwang-Soon (Department of Chemical Engineering, Sogang University) ;
  • Park, Jinhoon (Department of Chemical Engineering, Sogang University) ;
  • Lee, Jay H. (School of Chemical Engineering, Purdue University)
  • Published : 1999.10.01


An optimal control technique designed for simultaneous tracking and quality control for batch processes. The proposed technique is designed by transforming quadratic-criterion based iterative learning control(Q-ILC) into linear quadratic control problem. For real-time quality inferential control, the quality is modeled by linear combination of control input around target qualify and then the relationship between quality and control input can be transformed into time-varying linear state space model. With this state space model, the real-time quality inferential control can be incorporated to LQ control Problem. As a consequence, both the quality variable as well as other controlled variables can progressively reduce their control error as the batch number increases while rejecting real-time disturbances, and finally reach the best achievable states dictated by a quadratic criterion even in case that there is significant model error Also the computational burden is much reduced since the most computation is calculated in off-line. The Proposed control technique is applied to a semi-batch reactor model where series-parallelreactions take place.