The risk analysis of reservoir operation based on uncertain theory

Risk analysis is essential to reservoir operation. In this study, a new analysis for reservoir operation is proposed to enhance the utilization rate of the flood water from the Three Gorges Reservoir (TGR) during the flood season. Based on five scenarios of hydrology forecasting with the adaptive neuro-fuzzy inference system (ANFIS), a multi-objective optimum operation was implemented employing the risk control constraints of the genetic algorithm (GA) for the TGR. The results of this analysis indicated that the optimum hydropower generation was 5.7% higher than the usual operating hydropower generation, which suggested that, during flood season, it would be beneficial to increase hydropower generation from reservoirs, while maintaining a safe degree of flood risk.

Download Full-text

Fuzzy Representation of Environmental Flow in Multi-Objective Risk Analysis of Reservoir Operation

10.21203/rs.3.rs-295898/v1 ◽

2021 ◽

Author(s):

Jiqing Li ◽

Jing Huang ◽

Pengteng Liang ◽

Jay R. Lund

Keyword(s):

Risk Analysis ◽

Reservoir Operation ◽

Fuzzy Theory ◽

Environmentally Friendly ◽

Aquatic Organism ◽

Environmental Flow ◽

Multi Objective ◽

Objective Risk ◽

Survival And Reproduction ◽

Fuzzy Representation

Abstract In the context of water shortages, environmental flow is the key to alleviating the negative environmental impact of reservoir operation. Environmentally, the suitable stream flow for the survival and reproduction of aquatic organisms is a varying range, although most of studies now give it a fixed value, which leads to unreasonable resource allocations. In this study, we proposed a fuzzy representation of environmental flow by using the fuzzy theory and the ecological hydraulic radius. Furthermore, we used the Three Gorges-Gezhouba cascade reservoirs as a study case and Four Major Chinese Carps as indicator species. In addition, a multi-objective operation optimization model was established, which solved by the Evolver Palisade software, and a multi-objective risk analysis method was proposed based on the design reliability and risk rate of various benefit operations. The results show that: (1) Based on the environmental flow membership function, flow ranges suitable for the aquatic organism survival and reproduction at specific locations can be determined to help guide reservoir discharge. (2) Taking environmental flow membership as an optimization objective rather than a constraint is conducive to formulating environmentally friendly reservoir operation schemes and make more rational use of water resources. (3) The multi-objective risk analysis can avoid the one-sidedness of a single objective and analyze the risks brought by various benefit operations. Ecological demand has long been a factor considered when formulating reservoir operation schemes. Following the environmentally friendly operation scheme is helpful to protect the environment and maximize the overall benefits of reservoirs.

Download Full-text

The Advances in Risk Analysis of Reservoir Operation Research

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.1993 ◽

2012 ◽

Vol 594-597 ◽

pp. 1993-1997 ◽

Cited By ~ 1

Author(s):

Yan Ye ◽

Guang Wen Ma ◽

Yuan Bo Zhang

Keyword(s):

Risk Analysis ◽

Reservoir Operation ◽

Operation Research ◽

Influence Factors ◽

Risk Identification ◽

Deterministic Theory ◽

Multiple Factors ◽

Reservoir Inflow ◽

Operation Risk ◽

The Impact

There are many uncertain factors in the process of reservoir’s operation. For the reasons, the "deterministic theory" must turn to" probability theory", and it becomes necessary to strengthen risk analysis. Summarize the connotation of reservoir risk analysis, progress in research of risk analysis for reservoir inflow forecasting, risk analysis for reservoir operation, risk analysis for flood protection and flood discharge , and reservoir multi-objective risk analysis. There are so much influence factors and much of them uncertainly, not enough research on multiple targets and multiple factors, not much apply on new risk analysis theories and methods. Therefore, it should research more on the fields of risk identification, reducing the impact of human factors, new analysis methods and coupling methods.

Download Full-text