Optimal Flood Control Method for Gate-Controlled Reservoir System Based On PSO Algorithm

 2021.9.23.

The great leader Comrade Kim Jong Il said as follows:

"We should build a large number of structures such as dams and barrages on rivers and take good care of them. Only then can we prevent damage from flooding and add beauty to the landscape of the country as well."

To build and manage properly various facilities including dams and barrages in rivers and streams is an important and fundamental issue for preventing flood damage and making rational use of water resources.

The Faculty of Global Environmental Science of Kim Il Sung University proposed a method for the reservoir water gate management to ensure the safety of the dam in flood periods in cascade reservoirs and to prevent flood damage in downstream of reservoirs, and made some successes in the field of flood run-off control on complex reservoir system.

In flood control in gate-controlled reservoir, the discharge flow process is performed by opening and closing the reservoir gates.

However, it is a very difficult and complex problem to determine how to control the water gate of each reservoir during the flood period in a reservoir system consisting of several reservoirs.

It is a key issue in reservoir flood management to determine the optimal operating rules of the reservoir system composed of flood-control gates that are wide opened in time according to the discharge characteristics of gate-controlled reservoirs during the flood period.

We proposed a new optimization method based on PSO algorithm combined with the rearrangement method of partial solution groups to determine the optimal operating rules of the reservoir system consisting of flood control gates that are fully opened in due course.

Unlike the previous studies where the decision variable is the discharge process when applying PSO algorithm, this method adopted the PSO algorithm that takes the opening times of flood control gates as the decision variable.

To prove the proposed method, a flood control calculation is carried out in a reservoir system consisting of two reservoirs located in upstream of the River "P" and their tributaries and the performances of the PSO algorithm is compared with the progressive optimality algorithm (POA) using discharge flow process as the decision variables.

Validation results show that the proposed method is better than the two methods and sufficiently reflects the demand of reservoir managers, which can be effectively applied to the determination of optimal operating rules of the gate-controlled reservoirs during the flood period.

In this way, we could prevent flood damage of the downstream of reservoir by getting the maximum flood amount after control at the downstream of reservoir to be smaller than the maximum flood amount of natural state, while protecting the reservoir structure safely during flood period in a reservoir system composed of gate-controlled reservoirs.

The results of this study were published in Journal of Hydrology, an authoritative SCI-level international academic journal, under the title of "A study on optimal operation of gate-controlled reservoir system for flood control based on PSO algorithm combined with rearrangement method of partial solution groups".(https://doi.org/10.1016/j.jhydrol.2020.125783)