Two-stage frequency regulation for wind turbines with adaptive coefficients and optimized power trajectory [PDF]
International Journal of Electrical Power & Energy SystemsWind turbines support grid frequency by rotor decelerating and then accelerating, but the instant power imbalance caused by rotor speed recovery may lead to a secondary frequency drop.
Zhiting Zhou +5 more
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Inertia and Droop Frequency Control Strategy of Doubly-Fed Induction Generator Based on Rotor Kinetic Energy and Supercapacitor [PDF]
Energies, 2020 The large-scale application of wind power eases the shortage of conventional energy, but it also brings great hidden danger to the stability and security of the power grid because wind power has no ability for frequency regulation.
Xiangwu Yan, Xuewei Sun
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Optimal Process Control for Rotor Speed Recovery and Secondary Frequency Drop Mitigation in Wind Turbine Frequency Regulation [PDF]
ProcessesDriven by the demand for low-carbon and sustainable development, power systems are increasingly transitioning toward higher proportions of renewable energy and power-electronic interfaces, leading to a growing requirement for wind turbines to provide inertia support and frequency regulation (FR). Wind turbine kinetic energy-based FR inherently involves
Liqing Yang +3 more
openaire +2 more sources
Distributed Finite-Time Secondary Frequency and Voltage Restoration Control Scheme of an Islanded AC Microgrid [PDF]
Energies, 2021 To solve the problems of frequency and voltage deviation caused by the droop control while meeting the requirements of rapid response, a distributed finite-time secondary control scheme is presented.
Junjie Ma +3 more
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Optimized Temporary Frequency Support for Wind Power Plants Considering Expanded Operational Region of Wind Turbines [PDF]
CSEE Journal of Power and Energy SystemsWind power plants (WPPs) are increasingly mandated to provide temporary frequency support to power systems during contingencies involving significant power shortages.
Zhengyang Hu +3 more
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Improved Frequency Control Strategy for Offshore Wind Farm Integration via VSC-HVDC [PDF]
Energies, 2022 Voltage source converter based high voltage DC system (VSC-HVDC) has become a very promising solution to integrate offshore wind farm. However, the equivalent inertia of the modern power system with large renewable energy integration becomes small, which
Rui Zeng, Yizhen Wang
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Cell‐free DNA kinetics in response to muscle‐damaging exercise: A drop jump study [PDF]
Experimental PhysiologyA significant increase in circulating cell‐free DNA (cfDNA) occurs with physical exercise, which depends on the type of exertion and the duration. The aims of this study were as follows: (1) to investigate the time course of cfDNA and conventional ...
Ema Juškevičiūtė +5 more
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Study on Quantitative Evaluation Index of Power System Frequency Response Capability [PDF]
Energies, 2022 Frequency stability is an important factor for the safety and stability of the power system operation. In a traditional power system, the operation stability is ensured by the inertia response, primary frequency modulation, and secondary frequency ...
Cheng Chi, Hai Zhao, Jiahang Han
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Alterations in Spectral Attributes of Surface Electromyograms after Utilization of a Foot Drop Stimulator during Post-Stroke Gait [PDF]
Frontiers in Neurology, 2017 BackgroundA foot drop stimulator (FDS) is a rehabilitation intervention that stimulates the common peroneal nerve to facilitate ankle dorsiflexion at the appropriate time during post-stroke hemiplegic gait. Time–frequency analysis (TFA) of non-stationary
Rakesh Pilkar +4 more
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Research on DFIG-ES System to Enhance the Fast-Frequency Response Capability of Wind Farms [PDF]
Energies, 2019 With the increasing penetration of wind power generation, the frequency regulation burden on conventional synchronous generators has become heavier, as the rotor speed of doubly-fed induction generator (DFIG) is decoupled with the system frequency.
Sijia Tu, Bingda Zhang, Xianglong Jin
doaj +2 more sources