A robust warning generation method for non-linear systems is presented for forecasting abnormal situations in process systems. Predictive signals were used to issue warning in contrast to traditionally used measured states of the process. Potential unsafe conditions were identified when the most aggressive controller is unable to keep the system within normal operating range, and one or more safety constraints are violated. Conversely, process is defined in safe mode when all the output and input constraints are obeyed by the system. A moving horizon predictor is used to predict the open-loop response of the process for a defined horizon. A global optimizer seeks a sequence of feasible inputs that can keep the closed loop response of the system within the safety limits. A process is considered to be in a normal state when a sequence of feasible inputs can be found that is able to keep the process outputs within the safety limits. The efficacy of the proposed method is demonstrated on a continuous stirred tank reactor (CSTR) with different disturbance scenarios. The results show that the proposed method is able to detect a violation of a safety limit significantly earlier compared to the traditional monitoring schemes based on alarms on the measured signals.

提出了一种用于非线性系统的鲁棒警告生成方法，用于预测过程系统中的异常情况。与传统使用的过程测量状态相比，预测信号用于发出警告。当最激进的控制器无法将系统保持在正常工作范围内，并且违反了一个或多个安全约束时，便会识别出潜在的不安全状况。相反，当系统遵循所有输出和输入约束时，将在安全模式下定义过程。运动水平预测器用于预测已定义水平的过程的开环响应。全局优化器寻求一系列可行的输入，这些输入可以将系统的闭环响应保持在安全范围内。当发现可以将过程输出保持在安全范围内的一系列可行输入时，就认为该过程处于正常状态。提出的方法在具有不同干扰场景的连续搅拌釜反应器（CSTR）上证明了其有效性。结果表明，与传统的基于测量信号警报的监视方案相比，该方法能够更早地检测出违反安全限值的情况。