长距离输水管渠结合系统闸阀联合调控方式研究

Joint Regulation of Gate and Valve in the Long-distance System of Combining Pipeline and Channel

输配水渠道系统在跨越河谷时往往采用倒虹吸管道,其弹性波波速较明渠重力波有数量级的差异,故探索闸阀这两种响应特性相差迥异的控制对象的控制逻辑差异和调控方式具有一定意义。在处理一维明满流数值计算时采用窄缝法将有压流和明流控制方程统一,选择前馈逻辑与反馈算法中的PI增益系数与动作频率几个要素进行研究对比。由于管道的响应速度较快,阀门无前馈时控制效果仍较为理想,阀门无反馈控制效果很差。选取了水位波动、闸门调整量及稳定时间等性能指标组合成综合指标GI,相较PI控制,阀门和闸门仅采用比例或积分控制时,GI分别变大了39%、17%和75%、55%。对于与算例类似的一般管渠结合系统,阀门可采用无前馈控制,但建议采用反馈控制。阀门可根据管道特性选择不同的控制方式,长管道可仅采用比例控制,避免流量震荡的管道可仅采用积分控制。主要研究方法、结果可用于输配水工程中无压-有压系统的控制器设计,有利于实现输配水系统的安全、高效及自动化运行。

The water transmission and distribution channel system often adopts the form of an inverted siphon when crossing a river valley.The elastic wave propagation speed is orders of magnitude different than the gravity wave speed in an open channel.Therefore,this article attempts to explore the control logic difference and control methods of gate and valve.The Preissmann slot model are used as the calculation methods to unify the pressure flow and open flow control equations.The feedforward logic and feedback algorithm are selected for research and comparison.Due to the faster response speed of the pipeline,the control effect of the valve without feedforward is still ideal,and the control effect of the valve without feedback is very poor.This paper selects the combination of performance indicators such as water level fluctuation,gate adjustment and stabilization time to form a general indicator GI.Compared with PI control,when the valve and gate are only controlled by proportional or integral control,GI has increased by 39%,17%and 75%,55%.For the general pipe and channel combination system similar to the calculation example in this paper,the valve can adopt no feedforward control,and feedback control is recommended.The valve can choose different control methods according to pipeline characteristics,and the gate is best controlled by PI.Proportional control only can be used for long pipelines,integral control only can be used for pipelines that avoid flow fluctuations.The main research methods and results of this paper can be used in the design of the controller for the pressureless-pressure system in the water distribution project to realize the safe,efficient and automated operation of the water distribution system.