Research On Multi-objective Operation Of Parallel Reservoirs For The Project Of Water Division From Han To Wei River

The project of water division from Han to Wei river is one of the important measures to alleviate the shortage of water resources in Guanzhong of Shanxi province. The project makes full advantage of the water resources in the upper reaches of the Hanjiang Basin which can improve the ecology of Weihe Basin and ensure ecological use of water, and most importantly it can alleviate the contradiction between supply and demand of water resources in Guanzhong area effiectively.The reservoirs of Huangjinxia and Sanhekou and its power station and pumping station of diverting water area of the project were taken as the research object in this paper. Based on the data of inflow from July 1954 to June 2009, the changed law of inflow series of reservoirs were studied by means of mathematical statistics and Copula function. Then, the typical years were selected by using the least square approximation method. The single objective and multi-objective optimal scheduling model were established to solve the optimal water division process of parallel reservoirs. The main achievements of this paper are as follows.(1) The process of the change of the year, the interannual, the intergenerational and the trend of the runoff for the reservoir of Huangjinxia and Sanhekou were analyzed in this paper.The allocation of water within the year is extremely uneven, the boundary between flood and dry season is clear and the water during the flood season is relatively large. The reservoir runoff of the Huangjinxia and Sanhekou reservoirs has showed a decreasing trend.(2) The wetness-dryness encountering about the inflow runoff for the reservoirs was calculated in the paper. The results show that there is large probability of synchronous wetness-dryness, strong correlation, small probability of asynchronism about the runoff series of Huangjinxia and Sanhekou reservoirs. At the same time, the probability when Huangjinxia and Sanhekou reservoirs are all in dry years is 20.79%, which showed that there are more period unfavorable to the dispath.(3 ) The typical years of inflow runoff about the reservoirs were selected in the paper.According to the results finally, we have choosed the 1958 as wet year, 1985 as flat year, and 1997 as the drought year.(4 ) Under the constraint of meeting the water transfer project task from Hanjiang to Weihe River, the average maximum generated energy model and the average minimum energy consumption model were established and solved about the parallel reservoirs of the project. The calculation results show that the more generated energy supplied from the parallel reservoirs, the larger water supply from Sanhekou, and at the same time the water supply from Huangjinxia to Guanzhong is decreasing, the energy consumption is increased. The smaller pump station energy consumption is, the more water supply from Huangjinxia to Guanzhong region, and the less with the water supplement to Sanhekou.(5) Under the constraint of meeting the water transfer project task from Hanjiang to Weihe River, the multi-objective optimization model based on the average maximum power output - the average minimum energy consumption was established and solved about the project. On this premise of certain amount of the water transfer, when the water supply from Sanhekou arrived at the critical point, along with the increased water transfer from Sanhekou, the increase for total energy consumption from pump station is far greater than the increase from power. The stronger connection between the parallel reservoirs is, the more energy consumption is increased.