Search Results (13)

To address the limited flexibility of pumped storage power stations (PSPSs) under hierarchical clearing of energy and ancillary service markets, this study proposes a joint clearing mechanism for multi-level electricity markets. A bi-level optimization model based on the Stackelberg game is developed to characterize the strategic interaction between PSPSs and the market operator. Simulation results on the IEEE 30-bus system demonstrate that the proposed mechanism captures the dynamics of nodal supply and demand, as well as time-varying network congestion. It guides PSPSs to operate more flexibly and economically. Additionally, the mechanism increases PSPS profitability, reduces system costs, and improves frequency regulation performance. This game-theoretic framework offers quantitative decision support for PSPS participation in multi-level spot markets and provides insights for optimal storage deployment and market mechanism improvement. Full article

The construction of pumped storage power stations (PSPSs) is undergoing rapid expansion globally. Detecting operational faults and defects in pumped storage units is critical, as effective diagnostic methods can not only identify fault types quickly and accurately but also significantly reduce maintenance costs. This study leverages the symmetry characteristics in the vibration signals of pumped storage units to enhance fault diagnosis accuracy. To address the challenges of selecting the key parameters (e.g., decomposition level and penalty factor) of the variational mode decomposition (VMD) algorithm during vibration signal analysis, this paper proposes an algorithm for an improved subtraction-average-based optimizer (ISABO). By incorporating piecewise linear mapping, the ISABO enhances parameter initialization and, combined with a balanced pool method, mitigates the algorithm’s tendency to converge to local optima. This improvement enables more effective vibration signal denoising and feature extraction. Furthermore, to optimize hyperparameter selection in the bidirectional long short-term memory (BILSTM) network—such as the number of hidden layer units, maximum training epochs, and learning rate—we introduce an ISABO-BILSTM classification model. This approach ensures robust fault diagnosis by fine-tuning the neural network’s critical parameters. The proposed method is validated using vibration data from an operational PSPS. Experimental results demonstrate that the ISABO-BILSTM model achieves an overall fault recognition accuracy of 97.96%, with the following breakdown: normal operation: 96.29%, thrust block loosening: 98.60%, rotor-stator rubbing: 97.34%, and rotor misalignment: 99.59%. These results confirm that the proposed framework significantly improves fault identification accuracy, offering a novel and reliable approach for PSPS unit diagnostics. Full article

This study investigates the sediment transport characteristics in the lower reservoir area of a pure pumped-storage power station (Pure-PSPS) to address the sediment abrasion issue under high sediment-laden conditions. By establishing a physical model and employing multivariate statistical analysis methods, we systematically reveal the multifactorial coupled influence mechanism of key parameters in the lower reservoir area on turbine sediment concentration (TSC), while developing a predictive TSC formula applicable to high-sediment Pure-PSPS based on sediment-carrying capacity theory and sediment mass conservation principles. The study indicates the following: (1) Under consistent basic parameters such as reservoir length, the decay rate of sediment concentration along the path from the reservoir inlet to the power station’s intake and outlet decreases to 30~80% under high inflow conditions, while under medium and low inflow conditions, the decay rate exceeds 80%. (2) The lower boundary of the median particle size adjustment range for suspended sediment gradually increases from 0.006 mm for 30- and 40-year flood recurrence intervals to 0.009 mm for an 80-year recurrence interval, and under the 80-year recurrence interval, the particle size fluctuation range converges to a high and narrow distribution of 0.009~0.011 mm. (3) The constructed linear regression model has an R² value of 0.8. The inflow sediment concentration (standardized coefficient β = 0.36) exhibits the strongest explanatory power for the dependent variable, followed by inflow discharge (β = 0.345) and the height difference between the intake/outlet and the silted bed surface (β = 0.319). (4) By optimizing the Adomian decomposition method, dimensional analysis, and multiple regression techniques, and based on sediment-carrying capacity theory and sediment mass conservation principles, this study derived and fitted a predictive formula for TSC in high-sediment-laden Pure-PSPS environments with favorable validation results. The research not only clarifies the interactive relationship between high-sediment-laden flow and turbine sediment concentration in Pure-PSPS but also fills the methodological gap in predicting operational conditions for pure pumped-storage power stations under extreme sediment scenarios. The established regular patterns provide a scientific foundation for the design and feasibility assessment of similar Pure-PSPS projects in sediment-rich rivers. Full article

The underground power houses of pumped-storage power stations (PSPSs) are highly complex, with interconnected and multidimensional structures, including various tunnels, such as the main and auxiliary power houses (MAPH), main transformer tunnel (MTT), tailrace gate tunnel (TGT), access tunnels (ATs), cable tunnels (CTs) etc. During intensive civil construction and electromechanical installation, fire risk becomes particularly prominent. Current research mainly examines fire incidents within individual tunnels, lacking comprehensive analyses of smoke spread across the entire cavern network. Therefore, in this study, a numerical model of a cavern complex in a PSPS was established to analyze smoke behavior and temperature distribution under various fire scenarios. The results indicated that when a fire occurred in the MAPH, the fire risk was relatively higher compared to fires in other places. Using the example of smoke spread from the MAPH to the MTT, the smoke spread process through key connecting caverns was analyzed. Initially, the temperature and velocity were stable, and the CTs and traffic cable tunnel in the auxiliary powerhouse (TCTAP) were the main smoke paths. After 7 min, the heat release rate (HRR) became stable, and CTs and ATs became the main paths for smoke spread, which could provide a reference for improving fire design in underground cavern systems. Full article

The construction period of pumped storage power stations (PSPS) generates amounts of production wastewater, which may contain pathogenic bacteria and antibiotic resistance genes (ARGs) in these bacteria, potentially posing environmental and health risks. This study used the metagenome approach to analyze the distribution of microorganisms, ARGs and their correlation with water quality indicators in wastewater collected from two typical PSPSs. Coagulation system wastewater exhibits strong alkalinity (11.88), and aggregate system wastewater has high suspended solids (SS, 8 × 10⁴ mg/L), resulting in lower richness and diversity of bacterial communities. Serpentinimonas, a kind of alkaliphilic bacteria, had the highest relative abundance (48.58–99.7%). The ARG subtypes obtained conferred wastewater resistance to tetracycline, macrolide, fluoroquinolone and so on, but wastewater treatment has limited removal effect on ARGs. The results indicate that resistant bacteria and resistance genes can still be present and distributed under highly alkaline conditions, and the removal efficiency of ARGs by wastewater treatment in PSPS is limited. Attention should be given to the environmental and health risks posed by production wastewater, thereby providing a theoretical basis for the sustainable development of the PSPS industry. Full article

This study analyzes the ambient vibrations induced while running the Mount Changlong pumped-storage power station (PSPS). The ground vibration data of the power station during its operation were acquired with vibration sensors. Different units were selected and compared under working conditions, and the conclusions were as follows: (1) Ambient vibrations induced by the running of units constituted the primary source of vibration, and they attenuated as the distance increased. (2) The vibration acceleration under pumping conditions was larger than that under power generation conditions, and the ground vibration acceleration increased with an augmentation of the power. (3) The running of adjacent units generated mutual interference, and the types of units were different, which led to complex variations in the spectrum maps. (4) The vibration acceleration of the lower flat tunnel was prone to surpassing the standard when the number of units running together exceeded three. Full article

In this paper, a 1D process-based numerical model is established to study the sediment concentration via the turbine (TSC) and sedimentation of the lower reservoir and the upper reservoir of a certain pumped storage power station (PSPS), which is intended to be built on a sandy river. In addition, the sensitivity of TSC to some factors, such as suspended sediment gradation, the water level of the lower reservoir, and the coefficients of the sediment-carrying capacity formula, are analyzed in this paper. It is revealed that (1) the TSC will decrease by 30.8~34.5% when the incoming sediments of particle sizes less than 0.002 mm (which accounts for 3.95% of the totality) are replaced with incoming sediments of particle sizes between 0.002 mm and 0.004 mm. At the same time, the sedimentation thickness of the upper reservoir will decrease by 20.9%, and the siltation rate of the lower reservoir will increase by 2.4%. (2) The TSC will decrease by 12.6~13.1% as the water level of the lower reservoir rises by 17.55 m. This represents an increase of 8.4% in the average water depth and 26.4% in the storage capacity of the lower reservoir. At the same time, the sedimentation thickness of the upper reservoir will decrease by 32.2%, and the siltation rate of the lower reservoir will increase by 2.5%. (3) The TSC will decrease by 1.2~1.4% as the index of the sediment-carrying capacity formula m changes from 1.12 to 0.666, and the coefficient of the sediment-carrying capacity formula K changes from 0.2 to 0.6. At the same time, the sedimentation thickness of the upper reservoir will decrease by 7.2%, and the siltation rate of the lower reservoir will increase by 1.7%. Through the research on the sensitivity of the TSC, the direction and amplitude of the TSC changes with the boundary conditions are found, which provides a basis for the scheme comparison of specific projects and further supplements the prediction method system of the TSC. Meanwhile, the results remind researchers to pay more attention to the determination of boundary conditions and also provide the basis for the error analysis of the TSC. In summary, the results have certain guiding significance for the related research, and the sensitivity analysis results of the case could provide a reference for other specific projects. Full article

In order to ensure stable grid operatiFon and improve power quality, active or passive load rejection of pumped storage power stations (PSPS) inevitably occurs from time to time. The rapid closing of the guide vanes will cause drastic changes in pressure pulsations in the flow channel of the pump-turbine (PT) unit. The high-level pressure pulsations during load rejection transfer to the entire flow passage of the PT unit and generate strong vibrations on the head-cover and the connecting bolts. In this study, the 1D/3D joint simulation of the pipeline in a pumped storage power station and the turbine flow channels including the flow domains of the runner, crown chamber, band chamber, upper and lower labyrinths and pressure balance tubes is carried out first. Then, by applying the calculated pressure loads on the head-cover, stay vanes and bottom ring of the PT unit, the flow-induced dynamic behavior of the structures including the head-cover bolts is analyzed in detail. The results demonstrate that pressure loads on head-cover bolts change dramatically during the load rejection process. The flow-induced deformation of the inner head-cover during the load rejection is larger than that of other structures, and the flow-induced displacement and stress of different head-cover bolts are not uniform. The achieved conclusions in this study can be a useful reference for the design and operation of head-cover bolts for other PT units and high-head Francis turbine units. Full article

Pumped storage power station (PSPS) is an important clean energy project that plays an important role in ensuring the economical, safe, and stable operation of power systems and alleviating the contradiction of peak load regulation. Deformation analysis of the built and under construction PSPS dam was an important process of dam design and operation, which was of great significance to ensure the safe operation of hydraulic structures in the reservoir site. Nevertheless, there were many parameters involved in the model for analyzing dam deformation, which brings a large workload to the inversion and application of model parameters. In this study, the asphalt concrete face rockfill dam (ACFRD) of a PSPS in Ningxia, China, was taken as an example, a dam deformation 3D finite element analysis model based on the Duncan–Chang E-B model was constructed, and the orthogonal test method was used. The model parameters of the main rockfill zone, secondary rockfill zone, and reservoir bottom backfill zone were taken as factors for the sensitivity analysis of horizontal displacement of dam H, vertical displacement u, and asphalt concrete face tensile strain ε. The results showed that initial bulk modulus base K_b, damage ratio R_f, and initial elastic modulus base K had a relatively higher sensitivity and had significant impacts on the calculation results, while internal friction angle φ, fraction angle reduction φ, bulk modulus index m, and elastic modulus index n had a relatively lower sensitivity, which had no significant impact on the calculation results. Therefore, when using the Duncan–Chang E-B model to analyze the deformations of a PSPS dam and asphalt concrete face, K_b, R_f, and K should be the focus. Parameters with a low sensitivity could be determined by engineering analogy so as to achieve the purpose of improving calculation efficiency under the premise of ensuring calculation accuracy. Meanwhile, these parameters should also be strictly controlled during construction. The results of this study could provide a reference for the design and safety assessment of ACFRD in PSPS. Full article

Aiming at the many uncertain factors in the suitability evaluation of reinforced concrete lining of high-pressure pipelines, the set pair analysis (SPA) theory is used to establish the suitability evaluation model. By summarizing the key influencing factors of typical lining design criteria, five suitability evaluation indices are determined from three criteria, i.e., the minimum overburden criterion, the minimum principal stress criterion, and the hydraulic fracturing criterion. In order to fully consider the subjective and objective factors, the combination ordered weighted averaging (C-OWA) operator and the criteria importance through intercriteria correlation (CRITIC)-entropy weighting model (EWM) were used to construct a combination weighting method, and the weight coefficients of each index were comprehensively determined. Based on the SPA theory and calculation rules, combined with the lining suitability grading criteria, the five-element connection degree of each index and the comprehensive connection degree of each working point were calculated. In this study, the model is applied to the suitability evaluation of reinforced concrete lining at each drilling point of the high-pressure pipeline of a pumped storage power station (PSPS) in Shanxi Province. The results show that the proposed model consisting of subjective weight and objective weight can effectively avoid the error caused by a single weight method, which improves the evaluation sensitivity and rationality. Full article

The high and low-temperature performance of five hydraulic bitumen binders was evaluated using the dynamic shear rheometer (DSR) test, infrared spectrum test and direct tensile (DT) test. These hydraulic bitumen binders were respectively applied for several pumped storage power stations (PSPS) projects that were constructed or under construction. In order to relate the bitumen performance to the mixture performance, the slope flow test, three-point bending test and thermal stress restrained specimen test were carried out on hydraulic asphalt mixtures. The test results indicated the DSR rheological master curves can well distinguish the difference of each bitumen binder as well as the effect of polymer modification. Phase angle master curves, black diagrams and infrared spectra all indicated that several penetration-grade hydraulic bitumen binders were not virgin bitumen binders but were modified with relatively lower SBS polymer content when compared with traditional SBS-modified bitumen. When selecting the commonly used Karamay SG70 hydraulic bitumen as a reference, the normal SBS-modified bitumen was superior to other bitumen in terms of low- and high-temperature performance. Several slightly SBS-modified bitumen binders did not always show consistent results, which indicated that slightly modified bitumen may not really have the desired performance as expected. Therefore, SBS-modified bitumen will be more promising when dealing with extremely low or high temperatures. Bitumen performance was well compared with the mixture performance by using the bitumen creep, relaxation and tensile failure strain corresponding to the asphalt concrete slope flow, the maximum bending strain and the failure temperature, respectively. Compared with the traditional penetration, softening point and ductility test, it indicated that the DSR rheological test, creep test, direct tensile test and stress relaxation test can be used as more powerful tools for the characterization and optimization of hydraulic bitumen binders. Full article

Considering the goals of carbon peaking and carbon neutrality, along with their related policies, pumped storage power stations are set to develop quickly in China. The comprehensive performance of pumped storage power stations must urgently be evaluated, which can help investors in decision making and provide a reference for policymakers. In this paper, a hybrid novel fuzzy multicriteria decision-making (MCDM) method combining the fuzzy best worst method (BWM) and fuzzy TOPSIS was proposed for the comprehensive performance evaluation of pumped storage power stations in China. The fuzzy BWM was utilized to determine the criteria weights describing the comprehensive performance of pumped storage power stations, while the fuzzy TOPSIS was used to rank the comprehensive performance of pumped storage power stations. The index system for the comprehensive performance evaluation of pumped storage power stations in China incorporated economic, social, and environmental aspects. The comprehensive performance of four pumped storage power stations in China was empirically evaluated using the proposed hybrid novel fuzzy MCDM method, and the results indicate that pumped storage power station PSPS2 exhibited the best comprehensive performance, followed by pumped storage power stations PSPS1 and PSPS4, whereas pumped storage power station PSPS3 had the worst comprehensive performance. A sensitivity analysis and comparative analysis were also conducted. The results indicate that the proposed hybrid novel fuzzy MCDM method, combining the fuzzy BWM and fuzzy TOPSIS for comprehensive performance evaluation of pumped storage power stations, is robust and effective. Full article

The aim of the present paper is to investigate the use of the site “Potamon” Dam in the Prefecture of Rethymnon, Crete island, Greece, as a “virtual” renewable electricity supply of a pumped storage plant (PSP) in order to save and exploit the maximum possible part of the rejected wind energy of the autonomous power system of the Crete island. Taking into account the annual time series of the rejected power of the Crete power grid, the present research work targets the optimal configuration of the proposed PSP power station, including the sizing of its individual components as well as the determination of the capacity it could guarantee in order to be economically viable. The rejected electric energy from the actually operating wind farm production, which is not possible to be absorbed by the grid of Crete due to its stable operation limitations, could be absorbed by the here proposed pump storage plant (PSP) and converted to hydraulic energy. This can be achieved by pumping the water from the lower reservoir, which is the existing reservoir of the site “Potamon” Dam, with a storage capacity of about 22.5 million m³, up to the upper reservoir, which must be constructed accordingly. For the proposed PSP’s optimal size determination, established financial indices are used as an evaluation criterion for an investment life cycle of 25 years. The proposed PSP optimization is based on the dynamic mathematical model of the simulation results of the PSP’s hourly operation when incorporated in the Crete power grid for a whole year, performed in the Matlab 2016b computational environment (The MathWorks, Inc., Natick, MA, USA). The results of this research demonstrate the PSP’s technical feasibility and determine the PSP’s optimal CAPEX and the PSP’s whole life-time financial indicators in order that the whole investment be viable. Furthermore, the appropriate selling prices of the electricity produced from the proposed PSP were determined to achieve the PSP’s financial viability. The results comprise the key elements to prove the necessity for the establishment a.s.a.p. of the appropriate legal framework in order to have authorization to exploit the rejected RES (renewable energy sources) electric energy or the major part of it through PSPs, in priority in both the non-interconnected, as well as the interconnected power systems. Full article