大型输水明渠运行控制模式研究

Research on Canal Control of Large Scale Water Transfer Project

以南水北调中线干渠为背景,研究了大型输水明渠闸前常水位运行控制模式。基于下游运行控制概念,提出了包括前馈控制、反馈控制和解耦三个环节的分布式集中控制方案。其中前馈控制采用主动蓄量补偿方法,用于消除计划分水等可预测扰动的影响,加快渠道的响应与恢复速度。反馈控制采用水位-流量串级PI反馈控制方法,用于消除非计划分水等未知扰动和测量扰动的影响。采用流量控制器降低下游方向渠池间的耦合影响。设计专门的解耦算法,降低上游方向的耦合影响。在南水北调中线京石段渠道上进行了仿真试验。模拟了计划分水和非计划分水工况下,各闸门的操作过程和相应水位流量响应过程。结果表明,所设计的控制方案能够有效减少大型输水明渠的时间滞后,快速消除已知分水扰动和未知分水扰动的影响,使闸前水位快速回复至目标值,控制过程中的水位波动满足安全限幅。

Base on the Middle Route of South-to-North Water Diversion Project, canal control of large scale water transfer project is analyzed. Using the downstream operation and control concept, feedback control, feedforward control and decoupling sections of the control system are re- searched. Initiative volume compensation method is to deal with predictive disturbance. As for feedforward control method, it can compensate inherent delays and accelerate the response and recovery speed of the canal under constant downstream depth operation. Water level and flow cascade PI feedback control method is to deal with unpredictable disturbance. Flow rate controller of the cascade control system also functions as a decoupler in downstream direction. Simulation is carried out on Baijing-Shijiazhuang Section of the Middle Route of South-to-North Water Diversion Project. Cases including scheduled and unscheduled offtake changes are tested. The results show that the control model can reduce the impact of time delay, eliminate known and unknown disturbances quickly and efficiently. The constant downstream depth operation is well fulfilled and water level function is controlled within safety range.