외란을 고려한 회분공정의 공정확인법 = An advanced Process Identification Method for Batch processes under Disturbances

다국어 초록 (Multilingual Abstract)

This study introduces an advanced process identification method for the batch processes which are faced with not only the deterministic disturbances but also repetitive disturbances. This method utilizes input-output data from two batches, processes this data, and applies it to an existing process identification technique for processes with deterministic disturbance. By treating time-varying dynamics as deterministic disturbances—characterized by a varying mean, low frequency, and some degree of trend—the method approximates the disturbance using a combination of Laguerre functions. Also, this approach effectively reduces the impact of repetitive disturbance and mitigates the effects of time-varying dynamics within a single batch. The simulation study demonstrates that the proposed process identification method provides accurate process model for various types of processes, even in the presence of both repetitive and deterministic disturbance. The method effectively mitigates the impact of repetitive disturbances. In contrast, the existing process identification method fails to estimate accurate process models, as it does not account for repetitive disturbances. The proposed process can be used to predict the next batch’s behavior based on the identified model and tuning parameters. By combining this predictive capability with optimization techniques, it is possible to determine the optimal tuning parameters for the subsequent batch. The method is also applicable to advanced controllers, such as model predictive control and model reference adaptive control, and can be used to assess control loop performance in control performance monitoring systems, ultimately enhancing the productivity of batch processes. * A thesis submitted to the Council of the Graduate School of Kyungpook National University in partial fulfillment of the requirements for the degree of Master of Science in December 2024

목차 (Table of Contents)

• 1. 서론 1
• 2. 외란을 고려한 회분공정의 공정확인법 5
• 2.1 공정데이터 수집과 처리 7
• 2.2 제안 공정확인법의 이론적 전개 9
• 2.2.1 적분 변환을 이용한 공정 모델 계산 11
• 2.2.2 예측 에러 확인법을 이용한 외란 모델과 상태변수 초기치 계산 15
• 3. 모사 연구(Simulation Study) 20
• 3.1 (CASE1) 측정 노이즈를 포함한 3차 공정 24
• 3.2 (CASE2) 고차 공정(5차) 31
• 3.3 (CASE3) 비최소 위상(Non-minimum phase) 공정 38
• 3.4 (CASE4) 과소 감쇄 공정 45
• 4. 결론 52
• 참고문헌 53