2025
Shen, Jiawei; Pei, Ji; Wang, Wenjie; Yuan, Shouqi; Pavesi, Giorgio
In: Renewable Energy, vol. 253, 2025, ISSN: 18790682.
Abstract | Links | BibTeX | Tags: Acceleration transition process, Flow instability, High-efficiency operation, Micro-pumped hydro storage, Reversible mixed-flow pump, Variable-speed regulation
@article{Shen2025,
title = {Broader high-efficiency zone of micro-pumped hydro storage enabled by a variable-speed reversible mixed-flow pump: Taking acceleration as an example},
author = {Jiawei Shen and Ji Pei and Wenjie Wang and Shouqi Yuan and Giorgio Pavesi},
doi = {10.1016/j.renene.2025.123642},
issn = {18790682},
year = {2025},
date = {2025-01-01},
journal = {Renewable Energy},
volume = {253},
publisher = {Elsevier Ltd},
abstract = {Given the burgeoning renewables-based microgrids, it is crucial for a stable power supply to enable more flexible micro-pumped hydro storage by the reversible mixed-flow pump (RMFP) with a broad high-efficiency zone (HEZ). Variable-speed operation is the most effective method to regulate operating conditions for scenarios of the RMFP without the guide vane. To reveal the effect of variable-speed regulation on the HEZ, we test the energy characteristics of RMFP at four speeds based on a bidirectional hydraulic test bench. The experiment shows that the RMFP receives an HEZ that is expanded by 53.4 % in pump mode and 60.3 % in turbine mode by accelerating from 830 r/min to 980 r/min. Moreover, the transition process of the acceleration regulation under full load is simulated based on a validated CFD numerical scheme. It is indicated that the acceleration regulation not only improves the efficiency and hydraulic dissipation but also alleviates the flow instabilities. The peak-to-peak value and the amplitude of the dominant frequency of the pressure fluctuation in the runner can be reduced by up to 49.4 % and 46.2 %, respectively. This study highlights the broad high-efficiency zone and stable internal flow that variable-speed regulation contributes to the RMFP, aiming at enhancing the flexibility of micro-pumped hydro storage.},
keywords = {Acceleration transition process, Flow instability, High-efficiency operation, Micro-pumped hydro storage, Reversible mixed-flow pump, Variable-speed regulation},
pubstate = {published},
tppubtype = {article}
}
Given the burgeoning renewables-based microgrids, it is crucial for a stable power supply to enable more flexible micro-pumped hydro storage by the reversible mixed-flow pump (RMFP) with a broad high-efficiency zone (HEZ). Variable-speed operation is the most effective method to regulate operating conditions for scenarios of the RMFP without the guide vane. To reveal the effect of variable-speed regulation on the HEZ, we test the energy characteristics of RMFP at four speeds based on a bidirectional hydraulic test bench. The experiment shows that the RMFP receives an HEZ that is expanded by 53.4 % in pump mode and 60.3 % in turbine mode by accelerating from 830 r/min to 980 r/min. Moreover, the transition process of the acceleration regulation under full load is simulated based on a validated CFD numerical scheme. It is indicated that the acceleration regulation not only improves the efficiency and hydraulic dissipation but also alleviates the flow instabilities. The peak-to-peak value and the amplitude of the dominant frequency of the pressure fluctuation in the runner can be reduced by up to 49.4 % and 46.2 %, respectively. This study highlights the broad high-efficiency zone and stable internal flow that variable-speed regulation contributes to the RMFP, aiming at enhancing the flexibility of micro-pumped hydro storage.
