At present, the TV card model of PSD-PBA platform used in power system stability calculation cannot reflect the difference of units under multiple water heads, which is specifically reflected its dynamic response speed and anti-regulation accuracy. Based on the TV card model, an improved scheme is proposed. The water head-opening-power characteristics and power T_w characteristics of the model are obtained by program processing with the early operation data of the hydropower station, and then added to the improved model successively. The results show that the dynamic characteristics of the TV card model do not have the conditions for multi-parameter identification under the power mode primary frequency modulation. Moreover, the accuracy of anti-regulation under different loads is poor. The response characteristics of the improved model accord with the operation law of the real machine and can accommodate the difference of multiple water heads of the unit.

In recent years, part of water conveyance buildings of the main canal of the middle route of the South-to-North Water Diversion project have high water level and abnormal flow pattern, which lead to the risk of reduced water conveyance capacity. Therefore, it is urgent to assess the head loss. However, there are no monitoring stations inside the buildings, the project operation has not reached the designed scale, and the monitoring data lacks verification. The monitoring data of water level and discharge of the main canal during the large water delivery period in 2022 were collected, and the third-party hydraulic prototype measurement was carried out, and the monitoring data was reviewed and corrected. A calculation method of head loss was put forward using comprehensive head loss coefficient. The head loss of 143 out of 158 water transport structures in the main canal was calculated under enlarged flow. The results show that there is surplus in the distribution of head in the main canal. The total surplus head of the whole line is 3.05 m, among which the surplus in the section south to the Yellow River, the section between the Yellow River and the Zhang River, the section north to the Zhang River are 0.48 m, 1.06 m and 1.51 m respectively, accounting for 4%, 13% and 12% of the allocated head, respectively. The head loss of 40 water conveyance buildings exceeded the assigned value, among which were 31 inverted siphon, 4 aqueduct, 4 culvert and 1 tunnel.

At present, most variable-speed pumped-storage units use converters (AC excitation) to control power. There is a problem of reverse speed overshoot caused by rapid power changes, and the traditional governors are difficult to ensure good control effects, which affects the operating efficiency of variable-speed units. In order to study the control of the speed regulation system under the active power regulation of the variable speed unit, the speed regulation system of the variable speed pumped storage unit with adaptive backstepping sliding mode control (ABSMC) was proposed. Firstly, a mathematical model of the variable-speed pumped-storage unit speed control system including the optimal speed module was established. Secondly, taking the electromagnetic power as the system disturbance, an adaptive backstepping sliding mode controller for the variable-speed pumped-storage unit speed control system was designed and its stability was analyzed. Finally, a simulation test platform for the speed regulation system of the variable speed pumped storage unit was built, and the dynamic response simulation analysis of the speed of the variable speed pumped storage unit was carried out under the given power of the power generation condition. Compared with the sliding mode controller (SMC) and PID controller, the results show that the reverse overshoot of the controlled unit speed by the ABSMC is small, the adjustment time is short, and the effect of tracking the optimal speed is ideal. The effectiveness of the designed controller was verified.

In order to solve the upstream demand of small fish with weak swimming ability in the vertical slot fishway, an anti-flow cylinder is added to the migration channel between the long and short baffles. Hydro 3D open source code and LES-based numerical simulation technology are used to simulate the flow field in the vertical slot fishway before and after the anti-flow cylinder is added. According to the streamline distribution in the time-averaged flow field, the results show that the area of the vortex area in the pool is reduced after adding the blocking cylinder, which solves the problem of lack of sense of direction in the process of fish upstream in the traditional vertical slot fishway. The turbulent kinetic energy in the pool increases by 20%, which raised the energy dissipation of the water flow and reduced the energy consumption during the fish upstream process. The increase of vorticity around the long and short baffles and the blocking cylinder may have an adverse effect on the stability of the fish during swimming. However, according to the vortex structure, the vortex diameter behind the blocking cylinder is less than 76% of the body length of the small fish, so it has little impact on the stability of the fish during swimming. In summary, the setting of a flow blocking cylinder in the vertical slit fishway can improve the success rate of small fish upstream.

Dam displacement can directly affect the quality and operation safety of the dam. To find out the prediction model of the dam displacement, the temporal convolutional neural network model was used to predict the dam displacement. Three bionic algorithms of the sparrow search algorithm (SSA), the gray wolf algorithm (GWO) and the bat algorithm (BA) were improved by genetic algorithm, and three optimization algorithms including MSSA, MGWO and MBA were obtained. Taking root mean square error, determination coefficient, mean absolute error, efficiency coefficient and GPI index as precision index system, three combined weighted models including D-MSSA-TCN, D-MGWO-TCN and DMBA-TCN were constructed based on the deep belief network model (DBN). The results show that the MSSA algorithm had the highest operating efficiency and accuracy among all the algorithms. The accuracy of the three combined models was significantly higher than the rest of the models. The D-MSSA-TCN model had the highest accuracy among all models and can be recommended for estimating dam displacement.

After a blackout occurs resulting from an extreme disaster, the active distribution network with distributed generation and energy storage equipment can perform service restoration by island partition and network reconfiguration. To solve the service restoration problem for the active distribution network with uncertain wind power output, this paper proposes a two-stage service restoration model based on robust stochastic optimization. In the first stage, the event-wise ambiguity set of wind power output is constructed based on the historical data and the model which minimizes the outage cost is solved by the robust stochastic optimization method. In the second stage, the energy storage and controllable loads in the distribution network are used to track the wind power output, so as to optimize the scheduling during the fault recovery of the distribution network, which minimizes the outage cost and the total power loss. Finally, the superiority of the proposed the model and strategy is verified by the simulations of a modified IEEE 33-bus distribution system case.

The unsteady inflow process changes the hydrodynamic characteristics of the compound open channel and then determines the processes of material transfer and energy transfer in the floodplain and main channel. In order to study the influence of different unsteady inflow processes on the hydrodynamic characteristics of the compound open channel, indoor flume experiments were carried out to analyze the influence of different unsteady inflow processes on the water level, flow instability, and discharge per unit width process of the compound open channel, taking into account three factors: discharge amplitude, unsteady period, and rising duration. The results show that with the increase of discharge amplitude, the slope of wave peak growth of water level is greater than that of wave valley, and the wave height increases linearly. The discharge process of the unit width of the channel is deformed over time, and there is an obvious slow change process in the descending process of the main channel and the rising process of the floodplain. With the increase of the unsteady period, the wave peak of the water level increases, the wave valley decreases, and the wave height also increases linearly. The phenomenon of deformation of the unit width discharge of the channel over time disappears. The water level peaks and valleys change synchronously with the hydrologic skewness. When the hydrologic skewness (ratio of fluctuation water duration) is greater than 1, the rising process of the unit width discharge of the floodplain and main channel will also have an obvious slow change stage.

Water and sediment conditions are complicated in waters affected by the interaction of flood and tide. Therefore, the bend regulation in these waters is more difficult and its effect is more uncertain than that of ordinary rivers. This paper aims at the above problems by taking the treatment project of Wenjiayan bend as an example, which lies in Qiantang estuary. This treatment project consisted of the riprap protection at concave bank and retreating dike at the opposite bank combine with the shoal-cutting measure. Based on the observed hydrology and topography data for years, the variation of flow conditions, deep channel distribution, scouring elevation and siltation velocity before and after the project was analyzed. The results show that the bend effect is greatly weakened and flow conditions are improved after the treatment. Meanwhile, the deep channel in the bend reach moves from the foot of the dike to middle. These results can provide reference for measures to similar sharp-bend treatment. Meanwhile, the balance section area after the project implementation was predicted through the methods of river correlation coefficient method and section average statistics. The dredging conditions of the reach were determined, which can provide guidance to operation and maintenance for the subsequent project.

To study on water replenishment effect of ecological gate in the Tarim River Basin, the MODFLOW was used to establish the numerical simulation of the two-dimensional flow movement of the groundwater profile in the Wusiman section, and to analyze the evolution process of the groundwater flow field in 4 years. On this basis, the two schemes with or without ecological sluice were predicted and compared. The results show that in the fifth year under the two prediction schemes, compared with the single main river channel, the buried depth area less than 8 m in the study area increased by 6.62% by using the ecological sluice water conveyance scheme. The ecological gates restored the groundwater level far away from the ecological area of the main river channel, and the groundwater level on the north side of the section increased by 2-3 m on average. Compared with the single main channel water conveyance, the phreatic evaporation consumed by the increment of groundwater storage per cubic meter was reduced by 24.6%. The ecological sluice solves the problem that the groundwater level is difficult to recover in the ecological area far away from the main river channel under the traditional water conveyance mode, and creates conditions for the restoration of the river network ecosystem formed by multiple branches in the middle reaches and the safety belt of biodiversity along the main stream.

In order to analyze the influence of Poyang Lake Water Control Project on wetland vegetation habitat, MIKE21 was used to establish two-dimensional hydrodynamic model of Poyang Lake. Through the scenario of the typical years, the changes of water level and wetland vegetation growth habitat area in the main lake area and wetland nature reserve after the operation of the water conservancy project were simulated. The simulation results show that the operation of the Hydraulic Project has a great influence on the water level in the north of Songmen Mountain, and the influence degree gradually decreases from north to south. The operation of the hub has a great influence on the most suitable area and suitable habitat area of wetland vegetation in different hydrological years. The vegetation habitat surface varies greatly. After the operation of the hub, the dry year increases by 43.8 %, the normal year increases by 24.6 %, and the wet year is only 16.4 %. In October and November, the suitable habitat area can reach more than 2,000 km², accounting for about 2/3 of the total lake area, indicating that wetland vegetation will provide Siberian cranes with rich food sources and make them better survive and reproduce in wetlands. The simulation results reveal the influence of the Hydraulic Project on the change law of lake water level and wetland vegetation habitat interval under the current scheduling scheme, which can provide a theoretical reference for engineering construction and dispatching operation and maintenance.