变工况切换过程的Petri网自主预测与控制

摘要

针对变工况切换过程中切换点难以确定且切换准则不完善等问题，以大范围升温过程为例，利用仿人智能控制中“全压—零制动—稳态调节”的控制策略，提出了“预测 Petri 网”，即在 Petri 网中增加预测器，为 Petri网的变迁提供了判断元素。根据“预测—决策—再预测—再决策”的思想，增加切换过程的判断条件，实现了Petri网自主寻优过程。最后在实验室电加热炉装置上实验表明，在切换点不确定的情况下，在线寻找到切换点并增加了切换条件，使系统的切换更为平稳光滑，提升了系统响应速度和稳定性。%In switch process of varying duty, it is difficult to determine the switching point and the switching criterion is imperfect. Utilizing the “full-voltage, zero-braking, static-regulation” control strategy, a “predictive Petri-net” is proposed in the paper. A predictor is used in the Petri-net which provides judgment elements for the transition of Petri-net. Based on the idea of “prediction-decision-prediction-decision”, the judgment condition for switching process is added in this paper, and the self-optimization process of the Petri-net is realized. The temperature near the switching point is more stable. The test results on the laboratory furnace device show that when the switching point is uncertain, the predictive Petri-net can find the optimal switching point online and improve the response speed and stability of the system.