为提高实时洪水预报精度,提出了一种基于动态系统响应曲线洪水预报误差修正新方法。该方法将动态系统响应曲线引人洪水预报误差修正中,建立一种向误差源头追溯的动态反馈修正模型。此修正方法将新安江模型产流以下的部分作为响应系统,用线性差分近似代替非线性系统响应函数的偏导数值,得到时段产流量所对应的系统响应曲线。用实测流量和计算流量之间的差值作为信息,使用最小二乘估计原理,对产流量进行修正,再用修正后的产流量重新计算出流过程。该修正方法分别用理想案例和王家坝流域进行检验,结果证明此方法效果比传统二阶自回归模型有明显提高。
To improve the accuracy of real-time flood forecasting, a new effective error correction method based on dynamic system response curve (DSRC) was proposed in this paper. The dynamic system response curve was intro- duced to construct a dynamic error updating model for correcting the flood forecasting errors. In this study, the water sources separation and watershed concentration modules of the Xin'anjiang model were utilized as a response sys- tem. Substituting the linear difference for partial differential values of the response function in a nonlinear system, the system response curves of runoff time series can be obtained. Based on the observed and calculated discharge, the cal- culated runoff was corrected using the least square estimation, and the discharge hydrograph was recalculated with the corrected runoff. The method was tested in both ideal scenario and real case study. Comparing to the second-order au- toregressive error forecast model, the new method can significantly improve the accuracy of real-time flood forecas- ting. The new method has a simple structure without newly introduced parameters and effective.