2024
Wang, Wenjie; Qiu, Gai; Pei, Ji; Pavesi, Giorgio; Tai, Geyuan; Yuan, Shouqi
Effect of return channel on performance and pressure fluctuation of pump turbine Journal Article
In: Physics of Fluids, vol. 36, iss. 10, 2024, ISSN: 10897666.
Abstract | Links | BibTeX | Tags: Closure of Wicket Gate, Guide Vane Closure, Hydro plant control, Pumped hydro storage
@article{Wang2024,
title = {Effect of return channel on performance and pressure fluctuation of pump turbine},
author = {Wenjie Wang and Gai Qiu and Ji Pei and Giorgio Pavesi and Geyuan Tai and Shouqi Yuan},
doi = {10.1063/5.0229130},
issn = {10897666},
year = {2024},
date = {2024-01-01},
urldate = {2024-01-01},
journal = {Physics of Fluids},
volume = {36},
issue = {10},
publisher = {American Institute of Physics},
abstract = {To stabilize the operation of pumped storage power station, an orthogonal experimental design was proposed to optimize the return channel with the splitter blades of the pump turbine. The calculation results of various return channel models under multiple operating conditions indicated that inlet distance a1 and blade number z considerably affect the efficiency and flow pattern in the flow passage. The optimal scheme improved efficiency by nearly 3% at 0.6Qd. The Savitzky-Golay filtering method and Fast Fourier Transform were used to analyze the unsteady characteristics of the pump turbine in pump model. The amplitude of pressure pulsations at the blade passing frequency in the vaneless space and the interference zone between the guide vane and return channel reduced considerably, and the pressure pulsation amplitude in the vaneless zone decreased by 50%, 48%, and 20% for 0.6Qd, 1.0Qd, and 1.1Qd operating conditions. A Continuous Wavelet Transform was used to analyze frequency signals during the shutdown transition process. The optimization of the splitter blades improved the flow pattern in their corresponding flow passages and suppressed high-amplitude pressure pulsations in the unit for the stable operation of the pumped storage power station.},
keywords = {Closure of Wicket Gate, Guide Vane Closure, Hydro plant control, Pumped hydro storage},
pubstate = {published},
tppubtype = {article}
}
To stabilize the operation of pumped storage power station, an orthogonal experimental design was proposed to optimize the return channel with the splitter blades of the pump turbine. The calculation results of various return channel models under multiple operating conditions indicated that inlet distance a1 and blade number z considerably affect the efficiency and flow pattern in the flow passage. The optimal scheme improved efficiency by nearly 3% at 0.6Qd. The Savitzky-Golay filtering method and Fast Fourier Transform were used to analyze the unsteady characteristics of the pump turbine in pump model. The amplitude of pressure pulsations at the blade passing frequency in the vaneless space and the interference zone between the guide vane and return channel reduced considerably, and the pressure pulsation amplitude in the vaneless zone decreased by 50%, 48%, and 20% for 0.6Qd, 1.0Qd, and 1.1Qd operating conditions. A Continuous Wavelet Transform was used to analyze frequency signals during the shutdown transition process. The optimization of the splitter blades improved the flow pattern in their corresponding flow passages and suppressed high-amplitude pressure pulsations in the unit for the stable operation of the pumped storage power station.
2021
Cavazzini, Giovanna; Benato, Alberto; Pavesi, Giorgio; Ardizzon, Guido
Techno-economic benefits deriving from optimal scheduling of a Virtual Power Plant: Pumped hydro combined with wind farms Journal Article
In: Journal of Energy Storage, vol. 37, iss. May 2020, pp. 102461, 2021, ISSN: 2352-152X.
Abstract | Links | BibTeX | Tags: Pumped hydro storage, Renewable integration, Virtual Power Plant, Wind, Wind energy, Wind-hydro integration
@article{Cavazzini2021c,
title = {Techno-economic benefits deriving from optimal scheduling of a Virtual Power Plant: Pumped hydro combined with wind farms},
author = {Giovanna Cavazzini and Alberto Benato and Giorgio Pavesi and Guido Ardizzon},
url = {https://www.sciencedirect.com/science/article/pii/S2352152X21002103 https://doi.org/10.1016/j.est.2021.102461},
doi = {10.1016/J.EST.2021.102461},
issn = {2352-152X},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Journal of Energy Storage},
volume = {37},
issue = {May 2020},
pages = {102461},
publisher = {Elsevier Ltd},
abstract = {Wind and solar are renewable sources characterized by a great potential but a variable and unpredictable nature. Characteristics that provoke mismatch between power supply and demand which in turns are the source of network control issues. Problems manageable with the installation of large-scale energy storage like Pumped Hydro Energy Storage (PHES). To this purpose, the paper presents a techno-economic analysis for assessing the benefits deriving from the hybridization of a seawater PHES (sPHES) plant with an in-operation wind farm. Plants work as a Virtual Power Plant (VPP) instead of two separate unit. The hybridization aims to avoid the unbalances of the wind farm, having negative impact on both the grid and the wind farm owner itself. The unbalances cause unpredictable deviations from the predicted production and, hence, power production fluctuations faced by the grid with curtailments and/or calls in operation of fossil-fuelled power plants. A VPP techno-economic optimization on a daily bases is performed using the ASD-PSO algorithm while the optimization aim is the revenue maximization. Results show that a VPP composed by a sPHES and a wind farm and with a single owner, is able to manage the wind farm production, improving the revenue of 6.8% compared to plants acting separately on the market. The VPP approach is also convenient in the case of a joint venture between the plants owners. But, in this case, the revenue is increased only of 0.4% compared to plants working separately. Finally, results also highlight that, in the Italian electricity market, a sPHES plant alone is not able to generate sufficient revenue to guarantee a reasonable payback time while coupling it with a wind farm increases incomes and working days and avoid cost and grid issues in managing the unpredictable wind farm production.},
keywords = {Pumped hydro storage, Renewable integration, Virtual Power Plant, Wind, Wind energy, Wind-hydro integration},
pubstate = {published},
tppubtype = {article}
}
Wind and solar are renewable sources characterized by a great potential but a variable and unpredictable nature. Characteristics that provoke mismatch between power supply and demand which in turns are the source of network control issues. Problems manageable with the installation of large-scale energy storage like Pumped Hydro Energy Storage (PHES). To this purpose, the paper presents a techno-economic analysis for assessing the benefits deriving from the hybridization of a seawater PHES (sPHES) plant with an in-operation wind farm. Plants work as a Virtual Power Plant (VPP) instead of two separate unit. The hybridization aims to avoid the unbalances of the wind farm, having negative impact on both the grid and the wind farm owner itself. The unbalances cause unpredictable deviations from the predicted production and, hence, power production fluctuations faced by the grid with curtailments and/or calls in operation of fossil-fuelled power plants. A VPP techno-economic optimization on a daily bases is performed using the ASD-PSO algorithm while the optimization aim is the revenue maximization. Results show that a VPP composed by a sPHES and a wind farm and with a single owner, is able to manage the wind farm production, improving the revenue of 6.8% compared to plants acting separately on the market. The VPP approach is also convenient in the case of a joint venture between the plants owners. But, in this case, the revenue is increased only of 0.4% compared to plants working separately. Finally, results also highlight that, in the Italian electricity market, a sPHES plant alone is not able to generate sufficient revenue to guarantee a reasonable payback time while coupling it with a wind farm increases incomes and working days and avoid cost and grid issues in managing the unpredictable wind farm production.
