A fast water level optimal control method based on two stage analysis for long term power generation scheduling of hydropower station

摘要

water level optimal control (WLOC) has been one of the most important issues in reservoir optimal operation. To deeply understand WLOC in reservoir optimal operation, two stage analysis (TSA) of long term power generation scheduling of hydropower station (LSHS) is carried out, and the optimality condition for two stage problem of LSHS is derived with the assumption that there is no deserted outflow. Based on the idea of divide-and-conquer, a multistage problem is divided into several sub-problems composed of two-stage problems. The fast water level optimal control (FWLOC) method based on TSA is proposed according to the foregoing idea. And improved FWLOC-TSA extend FWLOC-TSA with the correction strategy for deserted outflow. Then, taking Xiluodu and Three Gorges Reservoir as examples, the proposed methods are applied to solve the problem of LSHS to test their effectiveness and efficiency. Meanwhile, the dynamic programming (DP) that can obtain the optimal solution of LSHS is used for comparison in the experiments. The experimental results demonstrate that the improved FWLOC-TSA works the same as DP. Especially the mean calculation time of improved FWLOC-TSA is about 1 ms, which has a remarkable performance compared with the calculation time of DP.