Optimization of Year-End Water Level of Multi-Year Regulating Reservoir in Cascade Hydropower System Considering the Inflow Frequency Difference

Zhiqiang Jiang,Xiang Liao,Peibing Song

doi:10.3390/en13205345

Abstract

In order to analyze the year-end water level of multi-year regulating reservoir of the cascade hydropower system, this paper studied the joint operation optimization model of cascade reservoirs and its solving method based on multi-dimensional dynamic programming, and analyzed the power generation impact factors of cascade system that contains multi-year regulating reservoir. In particular, taking the seven reservoirs in the middle and lower reaches of Yalong River as an example, the optimal year-end water levels of multi-year regulating reservoir under the multi-year average situation and different inflow frequencies situation were studied. Based on the optimal calculation results of multi-dimensional dynamic programming, the inflow frequency difference considered operation rule of year-end water level of Lianghekou reservoir was extracted using the least square principle. The simulation results showed that, compared with the fixed year-end water level in multi-year, the extracted rule can improve the cascade power generation by more than 400 million kWh in an average year, representing an increase of 0.4%. This result means that the extracted rule can give full play to the regulation performance of multi-year regulating reservoir and improve the conversion efficiency of hydropower resources in cascade system. This is of great significance to the practical operation of cascade reservoirs system that contains multi-year regulating reservoir.

Highlights

Hydropower energy is a kind of high-quality and efficient energy which is developing rapidly all over the world
It should be noted that the purpose of this paper is to extract the operation rules of multi-year regulating reservoir through simulation calculation, so the data used in this paper are all historical data
In order to analyze the variation of power generation of cascade system under different year-end water levels of Lianghekou reservoir, we take 5 m as the discrete interval, (2785 m–2845 m) as the discrete range, and get different discrete year-end level values, i.e., 2785 m, 2790 m, 2795 m, 2800 m, 2805 m, 2810 m, 2815 m, 2820 m, 2825 m, 2830 m, 2835 m, 2840 m, and 2845 m

Summary

Introduction

Hydropower energy is a kind of high-quality and efficient energy which is developing rapidly all over the world. It has the characteristics of being clean and pollution-free, renewable, low operation cost, fast start-up and shutdown speed, rapid output response, etc. The fast response to power load makes hydropower energy often be used as peak load and frequency modulation power supply, system load standby power supply, etc.

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Methods

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Conclusion