The Modeling Theory And Solving Methods Of Operation Rule For Water Quantitiy

With the development and implementation of comprehensive utilization thoughts and integrity view in the fields of water resources management, the water resources exploration pattern has experienced a transformation process from "individual project, independent operation" to "multi-projects, joint operation". The water resources system presents more obvious complicated characteristics. In addition, many mutli-reservoirs and national water supply-and-drainge system have been gradually constructed in China. The original single-reservoir operation chart and operation theory can not satisfy the practical requiment of canalization characteristics of multi-reservoir and networked characteristics of water supply-and-drainge system. Therefore, it is necessary to build more perfect water resources system analysis methods and operation theory system. In view of that, this paper takes the water-supply multi-reservoir system, the multi-reservoir system in the inter-basin water-transfer project and the drainage system in agriculture watershed as the research objects to study the rule forms, modeling and solving methods for water-supply multi-reservoir system and agriculture drainage system opeation. The water-supply muti-reservoir operation policy consists of water-supply rule, water-diversion rule, water-transfer rule and water-allocation rule. The detailed research continent includes such aspects as the folio wings:The research context and significance of water resources operation is pointed out at the beginning. And the research status of operation theory for the water-supply multi-reservoir system, the multi-reservoir system in the inter-basin water-transfer project and the drainage system in agriculture watershed is reviewed with emphasis. Based on summarizing the current research achievement, the main research continent in this study is introduced.The operation rule forms are important influencing factors on multi-reservoir operation results. After analyzing the disadvantages of the current reservoir operation policy form, this paper proposes an integrated reservoir operation chart combined with parametric rule and two-dimension reservoir operation chart for dual-reservoir system. In contrast to most common methods used in optimal control of reservoir systems requiring a large number of decision variables, parametric rule can make a radical reduction in the number of decision variables without yielding inferior solutions. However, parametric rule employs the standard operating policy to determine releases of reservoirs as much as demand only if there is enough water in the system, which may result in single periods of severe short supply during droughts. The purpose of this paper is to devise an operating rule for multi-reservoir system by combining parametric rule with the hedging rule to avoid catastrophic water shortage during droughts. In this way, decision variables to be optimized not only make a significant reduction compared with traditional operating rules, but also severe short supply during droughts can be controlled effectively. In order to make the water-supply decision objectively by considering the water storage in each reservoir, this study proposes a method of two-dimension reservoir operation chart for dual-reservoir system. Two common water task allocation rules of variable allocation ratios and compensation regulation rule are analyzed combined with two-dimension reservoir operation chart.In view of the Stackelberg structure of the multi-reservoir joint operation problem in inter-basin water transfer-supply project, this paper proposes a multi-reservoir joint operation policy, which consists of water transfer rule and water supply rule. In this study, a set of water transfer rule curves based on the storage of individual reservoir in the system is employed to illustrate the water transfer rule, which determines the starting conditions of water transfer and the allocation of the transferred water. The water supply rule is presented in the form of operation charts, the hedging rule curves of which for each water user divide the reservoir active storage into several operation zones. Besides, this paper proposes a bi-level programming (BLP) model in view of the Stackelberg structure of the inter-basin multi-reservoir joint operation problem, which includes the upper-level model for water transfer and the lower-level model for water supply. The improved particle swarm optimization algorithm is employed to solve the BLP model. An inter-basin water transfer project in North China is taken as the case study to verify the reasonability and validity of the model.After the multi-reservoir joint operating rule forms are determined and operation model is constructed, the derivation method is an important guarantee to obtain the optimal operation policy. For solving the multi-objective problem of determining multi-reservoir joint operation policy, a multi-objective particle swarm optimization algorithm (I-NSPSO) is proposed in this study. The I-NSPSO algorithm is embedded in the simulation-optimization model to explore the competing tradeoff relationship between the different optimization objectives of multi-reservoir water-supply operation. Set pair analysis (SPA) method can describe the similarity between the optimal water supply decision and the candidate water supply decision from the aspects of "same, different, opposite". The optimal water-supply multi-reservoir operating policy can be derived by improving the similarity degree between them. Based on that, a SPA based derivation method of water-supply multi-reservoir operating policy is proposed in this study.In view of the complex structure and hierarchy characteristics of the risk assessment system for water-supply multi-reservoir system, this paper employs the analytical hierarchy process (AHP) to determine the weight of the water-supply risk indexes for each water users. After that, an optimization model for multi-reservoir operation is constructed with the objective function of minimizing the water-supply risk. In this study, a general framework is proposed for exploring the maximum water-supply yield of the multi-reservoir system and analyzing water-supply risk.In this paper, the reservoir module and the pothole module in the SWAT model are modified to simulate the storing water of lake and paddy fields. The effect of water storage depth change at paddy different growth stage on runoff at watershed outlet is analyzed using the developed SWAT model. Considering the water storage role of paddy fields and lake, an optimization model for water body operation in agriculture drainage system is built in this study, with the optimization objective of minimizing the sum of the submerged loss, the pump station operation cost and rice production loss. In this optimal operation model, the decision variables include the lake drainage initialization standard with reference to the water level in the lake and numbers of initialized pumping stations at different operation periods. The inflows into the lake are taken as the input materials of the operation model, which are modeled by the developed SWAT model under different scerianls of water storage in paddy fileds. In the end, the optimal drainage operation policy is obtained under different scerianls of paddy water storage.With the research topic of water quantitiy operation, the water-supply multi-reservoir system, the inter-basin water-transfer multi-reservoir system and agriculture drainage system is chosen as the typical system to study their corresponding operation theory from the perspectives of water supply and drainage. The research results not only provide technical support for practical operation of large hydraulic projects, but also become beneficial supplement for the complex water resources system operation theory system.