Applied Energy最新文献_第5页

Thermo-hydro-mechanical modeling of geothermal energy systems in deep mines: Uncertainty quantification and design optimization 深矿井地热能源系统的热-水-机械建模：不确定性量化与设计优化

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-26 DOI: 10.1016/j.apenergy.2024.124531

Geothermal energy extraction through deep mine systems offers the potential to reduce the cost of geothermal systems while meeting the cooling needs of deep mines. However, the injection of cold water into the subsurface triggers strongly coupled thermo-hydro-mechanical (THM) processes that can affect the stability of underground excavations. This study evaluates the impact of geothermal energy extraction on the temperature and stability of a deep mine. By quantifying the sensitivity of the mine temperature and stability to various parameters, we propose a scheme to optimize geothermal energy production, while achieving rapid mine cooling and maintaining stability. We first evaluate the impact of geothermal operations on mine temperature and stability through THM numerical modeling. The simulations show that poro-elastic stress quickly affects mine stability, while thermal stress has a more significant impact on the long-term stability. We then use Distance-based Generalized Sensitivity Analysis (DGSA) to quantify parameter sensitivity. The analysis identifies the distance between the mine system and the geothermal system as the most influential factor. Other important parameters include the injection rate, injection temperature, well spacing, coefficient of thermal expansion, permeability, Young’s modulus, and heat capacity. Finally, we propose a DGSA-based optimization framework that accounts for subsurface uncertainty and validate the optimized results. Our results indicate that, with favorable geological conditions, a rational selection of system design parameters can enhance geothermal energy production while ensuring rapid mine cooling and stability. This study provides essential insights for the optimization of deep mine geothermal systems and supports effective decision-making.

通过深层矿井系统提取地热能有可能降低地热系统的成本，同时满足深层矿井的冷却需求。然而，向地下注入冷水会引发强烈的热-水-机械（THM）耦合过程，从而影响地下挖掘的稳定性。本研究评估了地热能提取对深层矿井温度和稳定性的影响。通过量化矿井温度和稳定性对各种参数的敏感性，我们提出了优化地热能生产的方案，同时实现矿井快速冷却并保持稳定。我们首先通过 THM 数值模型评估了地热作业对矿井温度和稳定性的影响。模拟结果表明，孔弹性应力会迅速影响矿井稳定性，而热应力对长期稳定性的影响更为显著。然后，我们使用基于距离的广义敏感性分析 (DGSA) 来量化参数敏感性。分析结果表明，矿井系统与地热系统之间的距离是影响最大的因素。其他重要参数包括注入率、注入温度、井间距、热膨胀系数、渗透率、杨氏模量和热容量。最后，我们提出了一个基于 DGSA 的优化框架，该框架考虑了地下的不确定性，并对优化结果进行了验证。我们的研究结果表明，在有利的地质条件下，合理选择系统设计参数可以提高地热能产量，同时确保矿井的快速冷却和稳定性。这项研究为优化深矿井地热系统提供了重要启示，并为有效决策提供了支持。

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引用次数: 0

A holistic analysis of environmental impacts and improvement pathways for the Brazilian electric sector based on long-term planning and life cycle assessment 基于长期规划和生命周期评估的巴西电力行业环境影响和改善途径整体分析

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-26 DOI: 10.1016/j.apenergy.2024.124505

Brazil presents a high share of renewable electricity generation, mainly due to its favorable hydroelectric potential. However, reports estimate that demand will grow substantially in the long term, requiring a significant diversification of the electricity mix. In this context, this paper analyzes how the environmental impacts of electricity generation tend to change over the horizon 2025–2050 in Brazil and identifies improvement opportunities accounting for environmental and economic factors. To do so, the Open Source Energy Modeling System (OSeMOSYS) is applied to estimate the composition of the electricity mix in 2050. Then, life cycle assessment (LCA) is used to evaluate the associated environmental impacts across ten categories. Lastly, hybrid weighted

ɛ

-constraint multi-objective optimization (MOO) is employed to evaluate which sources can be used to minimize climate change and the levelized cost of electricity while ensuring that other categories are reasonably restrained. The results indicate that the environmental performance of the Brazilian electricity matrix tends to deteriorate substantially, both when analyzing overall impacts and impacts per kWh. Moreover, the proposed MOO approach suggests that some sources, mainly hydropower, onshore wind, and centralized PV present an all-around economic/environmental performance and might be favorable for expanding the power system.

巴西的可再生能源发电比例很高，这主要得益于其良好的水力发电潜力。然而，有报告估计，从长远来看，巴西的电力需求将大幅增长，这就要求电力结构显著多样化。在此背景下，本文分析了 2025-2050 年期间巴西发电对环境影响的变化趋势，并根据环境和经济因素确定了改进机会。为此，本文采用开放源码能源建模系统 (OSeMOSYS) 估算 2050 年的电力组合构成。然后，使用生命周期评估（LCA）对十个类别的相关环境影响进行评估。最后，采用混合加权ɛ-约束多目标优化（MOO）来评估哪些能源可用于最大限度地减少气候变化和平准化电力成本，同时确保其他类别受到合理限制。结果表明，在分析总体影响和每千瓦时影响时，巴西电力矩阵的环境绩效都有大幅恶化的趋势。此外，建议的 MOO 方法表明，某些能源（主要是水电、陆上风电和集中式光伏发电）具有全面的经济/环境绩效，可能有利于扩大电力系统。

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引用次数: 0

Electrified catalytic steam reforming for renewable syngas production: Experimental demonstration, process development and techno-economic analysis 用于生产可再生合成气的电气化催化蒸汽转化：实验示范、工艺开发和技术经济分析

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-26 DOI: 10.1016/j.apenergy.2024.124556

Biomass is a key renewable feedstock for producing green fuels; however, renewable feedstock presents a high risk for catalyst deactivation and poor stability. In addition, the heat source of industrial reforming processes comes from fuel combustion and most heat is lost in the flue gas. In this study, a Ni/Al

_{2}

O

_{3}

/FeCrAl-based monolithic catalyst with a periodic open cellular structure (POCS) was designed and 3D-printed. A reforming process was then conducted by directly heating the catalyst using electricity instead of fuel combustion. This e-reformer technology was demonstrated in continuous catalytic steam reforming of biomass pyrolysis volatiles. A high H

_{2}

yield of

\approx

7.1 wt % of biomass has been obtained at a steam-to-biomass (S/B) ratio of 4.5, reforming temperature of 800

°

C and weight hourly space velocity (WHSV) of 310 h⁻¹, resulting in an energy consumption of 8 kWh_el kg⁻¹ biomass (66% energy efficiency). The results show a successful demonstration of the electrified technology with improvement potential; in addition, a process was designed and assessed economically for synthetic natural gas (SNG) production of 80 MW

_{HHV}

, comparing electrification and partial oxidation in different scenarios.

生物质是生产绿色燃料的主要可再生原料；然而，可再生原料具有催化剂失活和稳定性差的高风险。此外，工业重整过程的热源来自燃料燃烧，大部分热量在烟气中流失。本研究设计并三维打印了一种基于 Ni/Al2O3/FeCrAl 的具有周期性开放式蜂窝结构 (POCS) 的整体催化剂。然后，利用电力而不是燃料燃烧直接加热催化剂，进行重整过程。这种电子重整器技术在生物质热解挥发物的连续催化蒸汽重整中得到了验证。在蒸汽与生物质（S/B）比率为 4.5、重整温度为 800 °C 和重量小时空间速度（WHSV）为 310 h-1 的条件下，生物质的 H2 产率高达 ≈7.1 wt %，能耗为 8 kWhel kg-1 生物质（能源效率为 66%）。研究结果表明，电气化技术得到了成功展示，并具有改进潜力；此外，还设计了一种工艺，并对其进行了经济性评估，用于生产 80 MWHHV 的合成天然气 (SNG)，在不同方案中对电气化和部分氧化进行了比较。

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引用次数: 0

A dynamic migration route planning optimization strategy based on real-time energy state observation considering flexibility and energy efficiency of thermal power unit 考虑火电机组灵活性和能效的基于实时能态观测的动态迁移路径规划优化策略

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-26 DOI: 10.1016/j.apenergy.2024.124575

New energy resources compromising intermittent and fluctuating natures have been integrated into the power grid on a large scale, and thermal power units are obliged to promote the depth of deep peak shaving and flexible response-ability to cope with this new scenario. The safety, flexibility, and high efficiency of coal-fired units are the ultimate goals of its transformation, and there is a mutual influence and mutual restriction relationship among these indicators. To exploit the flexibility of thermal power units, take into account efficiency and safety, and play a supporting role in the new power system, a control strategy that weighs various indicators needs to be developed. Based on heat flow model and dynamic state space model, and updated matrix in real time, the key process parameters affecting the flexibility of heat transfer can be fully characterized. By using the observed state and calculation, the load response index and the energy efficiency index are optimized under the boundary constraint. The results show that the multi-objective optimization methods can avoid over regulation, reduce the flue gas flow by 3.23%–3.59%, and reduce the fluctuation of state quantity under the premise of satisfying the load response rate, about 2.32%–2.52% away from the safety boundary of the design temperature parameter to achieve the flexibility of frequency modulation, high efficiency of energy transmission and operation safety.

间歇性、波动性的新能源大规模并入电网，火电机组必须推进深度调峰和灵活响应能力，以应对新形势。燃煤机组的安全性、灵活性、高效性是其转型的最终目标，这些指标之间存在着相互影响、相互制约的关系。为了发挥火电机组的灵活性，兼顾效率和安全，并在新的电力系统中发挥支撑作用，需要制定权衡各项指标的控制策略。基于热流模型和动态状态空间模型，并实时更新矩阵，可以充分表征影响换热灵活性的关键工艺参数。利用观测到的状态和计算结果，在边界约束条件下对负荷响应指标和能效指标进行优化。结果表明，多目标优化方法可避免过度调节，减少烟气流量 3.23%-3.59%，在满足负荷响应率的前提下，减小状态量波动，距离设计温度参数安全边界约 2.32%-2.52%，达到调频灵活、输能高效、运行安全的目的。

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引用次数: 0

Power system benefits of simultaneous domestic transport and heating demand flexibility in Great Britain’s energy transition 英国能源转型中国内运输和供热需求同步灵活性对电力系统的益处

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124522

The increasing share of variable renewables in power generation leads to a shortage of affordable and carbon neutral options for grid balancing. This research assesses the potential of demand flexibility in Great Britain to fill this gap using a novel linear optimisation model PyPSA-FES, designed to simulate optimistic and pessimistic transition pathways in National Grid ESO Future Energy Scenarios. PyPSA-FES models the future power system in Great Britain at high spatiotemporal resolution and integrates demand flexibility from both smart charging electric vehicles and thermal storage-coupled heat pumps. The model then optimises the trade-off between reinforcing the grid to align charging and heating profiles with renewable generation versus expanding dispatchable generation capacity. The results show that from 2030, under optimistic transition assumptions, domestic demand flexibility can enable an additional 20–30 TWh of renewable generation annually and reduce dispatchable generation and distribution network capacity by approximately 20 GW each, resulting in a total cost reduction of around £5bn yearly. However, our experiments suggest that half of the total system cost reduction is already achieved by only 25% of electric vehicles alone. Further, the findings indicate that once smart electric vehicle charging reaches this 25% penetration rate in households, minimal benefits are observed for implementing smart 12-hour thermal storages for heating flexibility at the national level. Additionally, smart heating benefits decrease by 90% across all metrics when only pre-heating (without thermal storages) is considered. Spatially, demand flexibility is often considered to alleviate the need for north–south transmission grid expansion. While neither confirmed nor opposed here, the results show a more nuanced dynamic where generation capacities are moved closer to demand centres, enhancing connectivity within UK sub-regions through around 1000 GWkm of additional transmission capacity.

可变可再生能源在发电中的比例不断增加，导致电网平衡方面缺乏经济实惠且碳中和的选择。本研究利用新型线性优化模型 PyPSA-FES 评估了英国需求灵活性填补这一缺口的潜力，该模型旨在模拟国家电网 ESO 未来能源方案中的乐观和悲观过渡路径。PyPSA-FES 对英国未来的电力系统进行了高时空分辨率建模，并整合了智能充电电动汽车和蓄热耦合热泵的需求灵活性。然后，该模型优化了加强电网使充电和供热情况与可再生能源发电相一致与扩大可调度发电能力之间的权衡。结果表明，从 2030 年起，在乐观的过渡假设下，国内需求灵活性每年可使可再生能源发电量增加 20-30 太瓦时，并使可调度发电量和配电网容量各减少约 20 千兆瓦，每年可减少总成本约 50 亿英镑。然而，我们的实验表明，仅靠 25% 的电动汽车就已经实现了系统总成本减少的一半。此外，研究结果表明，一旦智能电动汽车充电在家庭中的普及率达到 25%，那么在全国范围内实施 12 小时智能蓄热系统以实现供热灵活性的收益将微乎其微。此外，如果只考虑预供暖（不考虑蓄热），智能供暖的效益在所有指标上都会减少 90%。在空间上，需求灵活性通常被认为是为了缓解南北输电网扩张的需要。虽然在此既未得到证实，也未遭到反对，但结果显示了一种更微妙的动态变化，即发电能力被转移到更靠近需求中心的地方，通过增加约 1000 千兆瓦公里的输电能力来增强英国次区域内的连接性。

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引用次数: 0

Aggregate power flexibility of multi-energy systems supported by dynamic networks 动态网络支持的多能源系统的总功率灵活性

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124565

The multi-energy system, encompassing electricity networks, district heating networks (DHNs), and hydrogen-enriched compressed natural gas (HCNG) networks, provides an alternative for promoting intermittent renewable energy accommodation and enhancing operational flexibility. This paper investigates the aggregate flexibility of the multi-energy system based on dynamic network models and admissible power fluctuation regions of decomposed subsystems. The dynamic processes within HCNG networks/DHNs are analyzed, and the inner-box method is employed to approximately quantify the individual flexibility of the dynamic networks. Furthermore, the optimal dispatchable regions of decomposed subsystems, accounting for internal gas/heating load uncertainties, are evaluated based on distributionally robust optimization. Through distribution-level power aggregation, the flexibility of the multi-energy system is quantified utilizing geometric methods. Numerical results on two test systems verify the effectiveness of the proposed methodology.

多能源系统包括电力网络、区域供热网络（DHN）和富氢压缩天然气（HCNG）网络，为促进间歇性可再生能源的利用和提高运行灵活性提供了一种选择。本文基于动态网络模型和分解子系统的容许功率波动区域，研究了多能源系统的总体灵活性。本文分析了 HCNG 网络/DHN 的动态过程，并采用内箱法近似量化了动态网络的单个灵活性。此外，考虑到内部燃气/供热负荷的不确定性，基于分布式稳健优化评估了分解子系统的最佳可调度区域。通过配电级功率聚合，利用几何方法量化了多能源系统的灵活性。两个测试系统的数值结果验证了所提方法的有效性。

引用次数: 0

Harnessing ultra-low-frequency vibration energy by a rolling-swing electromagnetic energy harvester with counter-rotations 利用带反向旋转的滚动摆动电磁能量收集器获取超低频振动能量

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124507

While ultra-low-frequency vibration is a common energy source, electromagnetic energy harvesting from such vibrations presents a challenge due to the low output performance caused by the slow variation of the magnetic field. In this work, we propose a rolling-swing electromagnetic energy harvester (RS-EMEH) that creates the counter-rotations between magnets and coils, thereby amplifying the magnetic field variation within a single cycle of ultra-low-frequency excitation. Simplified dynamic modeling, rigid-body simulation and finite-element analysis are performed to confirm its working mechanism. A unique alternating pole arrangement of magnets is adopted that enhances the output voltage by 2 times as compared to the traditional uniform pole arrangement. Moreover, the experiment of the RS-EMEH prototype validates the above simulation and demonstrates the positive correlation between electrical output and excitation in terms of both frequency (1.10 Hz to 1.50 Hz) and acceleration amplitude (0.05 g to 0.40 g). Further experiment shows that the harvested energy by the RS-EMEH can sustain the operation of a thermometer and calculator simultaneously for 161.3 s under the excitation at 0.4 g, 1.4 Hz for 92.6 s. Specifically, the RS-EMEH can provide milliwatt-level output at the walking speed ≤3.5 km/h, sufficient to power portable wireless low-power electronic devices. The findings of this work unveil the promising power generation and application potential of the rolling-swing electromagnetic energy harvesters for self-powered systems subject to ultra-low-frequency vibrations.

虽然超低频振动是一种常见的能源，但由于磁场变化缓慢导致输出性能较低，因此从这种振动中收集电磁能是一项挑战。在这项工作中，我们提出了一种滚动摆动电磁能量收集器（RS-EMEH），它能在磁铁和线圈之间产生反向旋转，从而在超低频激励的单周期内放大磁场变化。为确认其工作机制，我们进行了简化动态建模、刚体仿真和有限元分析。采用了独特的磁极交替排列方式，与传统的均匀磁极排列方式相比，输出电压提高了 2 倍。此外，RS-EMEH 原型的实验验证了上述模拟，并证明在频率（1.10 Hz 至 1.50 Hz）和加速度振幅（0.05 g 至 0.40 g）方面，电气输出与激励之间存在正相关。进一步的实验表明，在 0.4 g、1.4 Hz 92.6 s 的激励下，RS-EMEH 采集的能量可同时维持温度计和计算器工作 161.3 s。具体而言，RS-EMEH 可在步行速度≤3.5 km/h 时提供毫瓦级输出，足以为便携式无线低功耗电子设备供电。这项研究成果揭示了滚摆式电磁能量收集器在超低频振动自供电系统中的发电和应用潜力。

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引用次数: 0

Refined air-cooled battery sizing process for conceptual design of eVTOL aircraft 用于 eVTOL 飞机概念设计的改进型气冷电池尺寸确定流程

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124567

Recently, electric vertical takeoff and landing (eVTOL) aircraft have garnered significant interest as a primary mode of transportation in advanced air mobility (AAM). For the conceptual design of eVTOL aircraft, where a broad design space must be explored rapidly, a practical and reliable battery sizing process is essential. This process needs to employ models with low computational cost while comprehensively considering two key factors: voltage drop characteristics and thermal effects. However, existing research on battery sizing mainly relies on constant specific energy or power, neglecting these factors. This oversight can lead to significant discrepancies in battery sizing between the conceptual and detailed design phases. To address these limitations, this paper introduces a refined battery sizing process. Our approach incorporates models for battery voltage drop, heat generation, and a cooling system. A Thevenin equivalent circuit is used to model voltage drop and heat generation, with a novel calibration method developed for accurate predictions of voltage and temperature profiles. An air cooling system is adopted for its simplicity and lightweight design, and a corresponding model is constructed. Applying our process to eVTOL aircraft sizing revealed that incorporating temperature, along with the depth of discharge (DoD) and C-rate, as constraints in battery sizing led to a 4.6 % decrease in specific energy and a 4.2 % decrease in specific power. These findings underscore the importance of considering temperature in battery sizing. Additionally, sensitivity analyses provided insights into which thermal management system, air-cooled or liquid-cooled, is more appropriate for the battery under various operating conditions.

最近，电动垂直起降（eVTOL）飞机作为先进空中交通（AAM）的主要运输方式引起了人们的极大兴趣。在电动垂直起降飞机的概念设计中，必须快速探索广阔的设计空间，因此实用可靠的电池选型流程至关重要。这一过程需要采用计算成本较低的模型，同时综合考虑两个关键因素：压降特性和热效应。然而，现有的电池选型研究主要依赖于恒定的比能量或比功率，而忽略了这些因素。这种疏忽会导致电池尺寸在概念设计和详细设计阶段出现重大差异。为了解决这些局限性，本文介绍了一种经过改进的电池选型流程。我们的方法包含电池压降、发热和冷却系统模型。我们使用 Thevenin 等效电路来建立压降和发热模型，并开发了一种新的校准方法来准确预测电压和温度曲线。空气冷却系统因其设计简单、重量轻而被采用，并建立了相应的模型。将我们的方法应用于 eVTOL 飞机的选型时发现，将温度、放电深度 (DoD) 和 C 率作为电池选型的限制因素会导致比能量降低 4.6%，比功率降低 4.2%。这些发现强调了在确定电池尺寸时考虑温度因素的重要性。此外，敏感性分析还提供了在各种工作条件下哪种热管理系统（空气冷却或液体冷却）更适合电池的见解。

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引用次数: 0

Harnessing acrylic-PVDF binders in paint formulation for enhanced passive cooling performance 利用涂料配方中的丙烯酸-聚偏二氟乙烯（PVDF）粘合剂提高被动冷却性能

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124510

Global energy consumption and climate change have caused an increase in urban heat islands effect and global warming, cooling lifestyles have been desired and cooling solutions have become challenging. Passive radiative cooling is a unique technology which utilizes the “atmospheric window” (8–13 μm) to emit thermal infrared radiation to the atmosphere. It does not require additional energy (i.e. electricity) input and has great potential for various applications. In general, the solar radiation would be reflected by the paint coating and existing thermal infrared radiation would be emitted from the surface to the atmospheres which would lead to lower surface temperature. In this work, titanium dioxide (TiO₂) cooling paint has been successfully fabricated under Malaysia's tropical climate. The effects of adding polyvinylidene fluoride (PVDF) along with acrylic as the binder for the paint were studied and various concentrations were tested to determine the optimum composition of the paint. The cooling paint is able to outperform the chosen commercial white paint in terms of cooling performance on various types of surfaces. Results obtained from field tests indicate that the cooling paint was able to achieve efficient cooling performance under direct solar irradiation. The average net cooling power of the titanium dioxide paint was 90.87 W/m². The relationship between weather conditions on the net cooling power of the cooling paint was also investigated.

全球能源消耗和气候变化导致城市热岛效应和全球变暖加剧，人们希望采用降温的生活方式，而降温解决方案也变得具有挑战性。被动辐射降温是一种利用 "大气窗口"（8-13 μm）向大气发射热红外辐射的独特技术。它不需要额外的能源（如电力）输入，在各种应用中具有巨大的潜力。一般来说，太阳辐射会被涂料涂层反射，现有的热红外辐射会从表面发射到大气中，从而降低表面温度。在这项工作中，二氧化钛（TiO2）冷却涂料已在马来西亚的热带气候条件下制造成功。研究了添加聚偏二氟乙烯（PVDF）和丙烯酸作为涂料粘合剂的效果，并测试了各种浓度，以确定涂料的最佳成分。这种降温涂料在各类表面上的降温性能优于所选的商用白色涂料。现场测试结果表明，冷却涂料能够在太阳直射下实现高效的冷却性能。二氧化钛涂料的平均净冷却功率为 90.87 瓦/平方米。此外，还研究了天气条件与冷却涂料净冷却功率之间的关系。

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引用次数: 0

A clustered federated learning framework for collaborative fault diagnosis of wind turbines 用于风力涡轮机协同故障诊断的聚类联合学习框架

IF 10.1 1区工程技术 Q1 ENERGY & FUELS

Applied Energy

Pub Date : 2024-09-25 DOI: 10.1016/j.apenergy.2024.124532

Data-driven approaches demonstrate significant potential in accurately diagnosing faults in wind turbines. To enhance diagnostic performance and reduce communication costs in federated learning with data heterogeneity among different clients, we introduce a clustered federated learning framework to wind turbine fault diagnosis. Initially, a lightweight multiscale separable residual network (LMSRN) model is proposed for each local client. The LMSRN model integrates a multiscale spatial feature derivation unit and a depthwise separable feature extraction unit. Subsequently, to tackle data heterogeneity among clients, canonical correlation coefficients of representations are extracted from the intermediate layers of local LMSRN models, and a representational canonical correlation clustering (RCCC) method is proposed to assess the similarity of local LMSRN models and group them into clusters. Finally, a global model is trained for each cluster. Real-world wind turbine data experiments showcase the superior performance of the proposed clustered federated learning framework over traditional methods in terms of diagnostic accuracy and computational speed. Additionally, the optimal choice of the number of clusters is also discussed.

数据驱动方法在准确诊断风力涡轮机故障方面展现出巨大潜力。为了提高诊断性能并降低联合学习中不同客户端间数据异构的通信成本，我们为风力涡轮机故障诊断引入了集群联合学习框架。最初，我们为每个本地客户端提出了一个轻量级多尺度可分离残差网络（LMSRN）模型。LMSRN 模型集成了多尺度空间特征推导单元和深度可分离特征提取单元。随后，为了解决客户端之间的数据异质性问题，从本地 LMSRN 模型的中间层提取表征的典型相关系数，并提出一种表征典型相关聚类（RCCC）方法来评估本地 LMSRN 模型的相似性，并将它们归类为聚类。最后，为每个聚类训练一个全局模型。真实世界的风力涡轮机数据实验表明，所提出的聚类联合学习框架在诊断准确性和计算速度方面都优于传统方法。此外，还讨论了聚类数量的最佳选择。

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引用次数: 0