渠道系统自动化运行是提高明渠输水系统水资源利用效率的有效途径,其基本思路是通过节制闸的实时调节维持渠道内的水位、流量在一定的目标状态。经典PID控制算法在应用到渠道控制中存在微分环节极易引起超调甚至系统失稳的问题,因而实际渠系控制器多采用比例积分环节(PI),其缺点是响应缓慢。为了提高渠系控制的响应速度、减小系统调节动作量,在PID算法的积分环节中引入启动阈值,并采用惯性环节串联补偿微分环节。采用ASCE的标准渠道测试算例进行建模仿真,计算结果表明改进算法在传统PID算法的基础上降低系统超调、减少闸门的调节量;在PI算法的基础上提高系统响应速度。
Automatic operation is an effective way to improve the utilization efficiency of water resource on ca- nal system. The basic idea is to maintain channels of water level and flow rate in a certain target state through re- al-time adjustment of the gate. Differential link of classic PID control algorithm easily leads to excessive over- shoot and even system instability, therefore PI controller without differential stage is commonly used in canal system. In order to improve the system response speed and reduce regulating action, starting threshold in the stage of the integral, with inertial factor for differential stage to improve the classic PID algorithm was intro- duced. Simulation was carried out for standard test cases from ASCE. Results showed that the modified algo- rithm could reduce the over shoot and decrease the adjustment of gate compared with traditional PID algorithm, and improve the system' s response speed in contrast to PI algorithm.