비전통 오일 생산 플랜트의 Direct Digital Control(DDC) 기반 통합 제어 시스템에 대한 이상상황 대응성과 운전 안정성의 정량적 평가 = Quantitative Evaluation of Abnormal Situation Response and Operational Stability of a DDC-Based Integrated Control System for Unconventional Oil

다국어 초록 (Multilingual Abstract)

Unconventional oil production plants are complex process systems characterized by highly viscous fluids, multiphase flow, thermal nonlinearity, long time delays, and strong inter-unit coupling. Under such conditions, conventional centralized control structures face limitations in achieving both rapid abnormal situation response and plant-wide operational stability. This study proposes a DDC(Direct Digital Control)-based distributed integrated control system as an alternative to conventional centralized control and quantitatively evaluates its performance. The proposed architecture consists of local DDC control nodes for each process subsystem and a supervisory optimization layer for plant-wide coordination and energy optimization. Five representative abnormal operating scenarios—namely inlet flow fluctuation, separator level deviation, heat exchanger degradation, circulation pump trip, and steam pressure variation—were defined. Performance was evaluated using Response Time, Maximum Deviation, Recovery Time, Energy Consumption Change, and Operational Stability Index(OSI). Results show that the proposed DDC-based structure achieves a 36.4% reduction in response time, 41.9% reduction in maximum deviation, 36.8% reduction in recovery time, and 38.3% reduction in energy consumption increase, with a 38.0% improvement in OSI. These results demonstrate that the proposed control system enhances disturbance rejection and operational stability, providing a practical framework for digital operation of unconventional oil production plants.