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Rear-surface water cooling for photovoltaic panels: A thermo-hydrodynamic pathway to high-efficiency and sustainable solar power in hot climates 光伏板的后表面水冷却:热流体动力学途径在炎热气候下实现高效和可持续的太阳能发电
IF 4.6 Pub Date : 2026-01-25 DOI: 10.1016/j.uncres.2026.100326
Wassim Salameh , Samer Ajeeb , Kamal Itawi , Mohamad Arnaout , Rabih Murr , Jalal Faraj , Mahmoud Khaled
Photovoltaic (PV) modules functioning in high-temperature environments face considerable efficiency declines as a result of increased cell temperatures, driving the need for innovative and resource-efficient cooling solutions. This study explores the rear-surface water cooling of photovoltaic modules through a coupled thermal–hydrodynamic numerical model, aiming to identify crucial design and operational parameters that influence thermal and electrical performance. The model undergoes initial validation using published experimental data for air-cooled PV systems, followed by an extension to include rear-surface water cooling as an added convective boundary condition. A thorough parametric analysis is conducted to evaluate the effects of duct height, flow regime, inlet water temperature, and climatic conditions on the reduction of module temperature and the improvement of electrical efficiency. The findings indicate that implementing rear-surface water cooling can lower the operating temperature of photovoltaic systems by as much as 20 % in hot urban environments, resulting in enhancements in electrical efficiency ranging from 15 % to 20 %, contingent on the hydraulic configuration employed. The analysis further illustrates that suitable duct geometry and flow management facilitate efficient cooling while minimizing water usage, underscoring the practicality of closed-loop operation. The proposed framework offers a physically consistent approach for designing and optimizing rear-surface water-cooled PV systems, effectively addressing significant limitations found in current studies that overlook the interplay between thermal and hydrodynamic effects. The results enhance the development of scalable PV cooling solutions tailored for hot climates and provide direction for future experimental validation and techno-economic evaluation.
由于电池温度的升高,在高温环境下运行的光伏(PV)模块面临着效率显著下降的问题,这推动了对创新和资源节能型冷却解决方案的需求。本研究通过热流耦合数值模型探讨了光伏组件的后表面水冷却,旨在确定影响热电性能的关键设计和操作参数。该模型使用已发表的风冷光伏系统实验数据进行了初步验证,随后扩展到包括后表面水冷作为附加对流边界条件。进行了全面的参数分析,以评估管道高度,流动状态,进水温度和气候条件对模块温度降低和电气效率提高的影响。研究结果表明,在炎热的城市环境中,实施后地表水冷却可以将光伏系统的工作温度降低20%,从而提高电力效率,提高幅度从15%到20%不等,具体取决于所采用的水力配置。分析进一步表明,合适的管道几何形状和流量管理有助于有效冷却,同时最大限度地减少用水量,强调闭环操作的实用性。提出的框架为设计和优化后表面水冷光伏系统提供了一种物理上一致的方法,有效地解决了当前研究中发现的忽视热和水动力效应之间相互作用的重大局限性。研究结果促进了针对炎热气候的可扩展光伏冷却解决方案的开发,并为未来的实验验证和技术经济评估提供了方向。
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引用次数: 0
Microbialite fabric evolution controlled by marine redox conditions in the Qigebrak Formation, NW Tarim Basin: Implications for hydrocarbon exploration 塔里木盆地西北部齐格布拉克组海相氧化还原条件下微生物岩组构演化及其油气勘探意义
IF 4.6 Pub Date : 2026-01-21 DOI: 10.1016/j.uncres.2026.100325
Chang Fang , Da Gao , Hui Zhou , Lili Huang , Yangxiao Hu , Ngong Roger Ngia
Microbialites constitute key archives for reconstructing the co-evolution of early life and Earth surface environments. Although the environmental controls on microbialite formation are widely acknowledged, the response of specific microbialite architectures to changes in pelagic ocean chemistry still remain poorly constrained. This paper integrates detailed field mapping, sedimentary facies analysis, and geochemical profiling of the Qigebrak Formation at the Xigou section on the northwestern margin of the Tarim Basin, to characterize microbialite fabrics and assess the role of contemporaneous marine redox conditions in shaping their development during the late Ediacaran. The microbialites at Xigou are well preserved and exhibit diverse fabrics, deposited in mid-to inner-ramp settings. Member II is dominated by laminated microbialites with subordinate clotted and binding fabrics. In contrast, Member III is typified by foam spongy fabrics, marking a significant shift in microbialite architecture. Bulk-rock δ13C values record a pronounced positive excursion (∼+5 ‰ to +6 ‰) at the base of the formation, followed by a prolonged interval of isotopic stability. This isotopic variation exhibits global correlation significance and, when combined with the Dengying Formation age constraints, limits the depositional interval to approximately 551.1 ± 0.7 Ma to 538.8 Ma. Trace element and rare earth element data from microbial components indicate that both δCe values and V/(V + Ni) ratios in Member III are markedly lower than those in Member II, reflecting a significant marine redox transition from anoxic to more oxic conditions during the late-Ediacaran ocean. This redox shift exerted a primary control on microbialite fabric development: anoxic conditions favored microbial mats accretion and preservation of laminated fabrics, whereas subsequent oxygenation enhanced organic matter degradation, facilitating the emergence and dominance of foam spongy fabrics. The fabric transition may also reflect increased ecological disturbance linked to the rise of metazoans, pointing to a potential coupling between microbialite decline and biotic innovation in the terminal Ediacaran. Our study underscores that changes in marine redox chemistry, coupled with ecological interactions, were primary controls on the evolution of microbialite in the late Ediacaran, and further elucidates the implications of these fabric transformations for hydrocarbon exploration.
微生物岩是重建早期生命与地球表面环境共同演化的重要资料。虽然环境对微生物石形成的控制已被广泛承认,但特定微生物石结构对远洋海洋化学变化的响应仍然知之甚少。本文综合了塔里木盆地西北缘西沟剖面奇格布拉克组详细的野外填图、沉积相分析和地球化学剖面,对埃迪卡拉世晚期微生物岩组构进行了表征,并评价了同时期海洋氧化还原条件对其发育的影响。西沟微生物岩保存较好,结构多样,沉积于斜坡中部至内侧。II段以层状微生物岩为主,并伴有凝块和结合织物。相比之下,成员III以泡沫海绵织物为典型,标志着微生物结构的重大转变。大块岩石δ13C值在地层底部记录了一个明显的正偏移(~ +5‰至+6‰),随后是一段较长的同位素稳定期。该同位素变化具有全球对比意义,结合灯影组年龄约束,将沉积区间限定在551.1±0.7 Ma ~ 538.8 Ma之间。微生物组分的微量元素和稀土元素数据表明,III段的δCe值和V/(V + Ni)比值均明显低于II段,反映了晚埃迪卡拉纪海洋由缺氧条件向多氧条件的显著氧化还原转变。这种氧化还原转变对微生物岩织物的发育起着主要的控制作用:缺氧条件有利于微生物席的聚集和层压织物的保存,而随后的氧化作用增强了有机物的降解,促进了泡沫海绵织物的出现和主导地位。结构的转变也可能反映了与后生动物的兴起有关的生态干扰的增加,指出了在埃迪卡拉纪末期微生物群的减少和生物创新之间的潜在耦合。本研究强调,海洋氧化还原化学的变化和生态相互作用是埃迪卡拉世晚期微生物岩演化的主要控制因素,并进一步阐明了这些结构变化对油气勘探的意义。
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引用次数: 0
Towards a sustainable energy future: Evaluating renewable energy options in Tunisia 迈向可持续能源的未来:评估突尼斯的可再生能源选择
IF 4.6 Pub Date : 2026-01-19 DOI: 10.1016/j.uncres.2026.100322
Sassi Rekik , Johnson Herlich Roslee Mensah , Ali Gassim Shetwan
Given the increasing threat of climate change, global warming, and depletion of fossil fuels, the adoption of renewable energy technologies (RETs) has become a crucial issue. Nevertheless, selecting the most appropriate technology is crucial. In this sense, developing decision support mechanisms for the identification of appropriate energy resources is one of the core decision-making challenges in the energy industry. In this paper, we address some renewable energy options for electricity generation in Tunisia namely solar photovoltaics (PV), concentrated solar power (solar CSP), onshore wind, and biomass, taking into account technical, economic, environmental, and social dimensions. This study employed a hybrid multi-criteria decision-making approach, combining CRiteria Importance Through Inter-criteria Correlation (CRITIC) and Evaluation based on Distance from Average Solution (EDAS), The considered alternative RETs were ranked and prioritized according to the proposed model. The results indicate that solar PV is the most promising renewable technology for Tunisia. Biomass is the least viable option. Validation through Monte Carlo simulation (MCS) largely corroborated these results, consistently placing solar PV first, followed by onshore wind. The only minor difference observed was an exchange in ranking between biomass and solar CSP. A sensitivity analysis was conducted to validate the outcomes and demonstrate the effect of changing the input data on the final results, revealing the considerable influence of cost-related factors on nearly all renewable energy technologies. Key differences in sensitivity were apparent, with Solar PV being more sensitive to electricity cost than capital cost, whereas solar CSP showed equal criticality to both. These distinctions imply that decision-making and risk prioritization must be tailored to each specific RET, prioritizing R&D for cost reduction and economies of scale for highly cost-sensitive technologies, and technological innovation and operational optimization for those sensitive to efficiency.
鉴于气候变化、全球变暖和化石燃料枯竭的威胁日益加剧,采用可再生能源技术(RETs)已成为一个关键问题。然而,选择最合适的技术是至关重要的。从这个意义上说,制定决策支持机制以确定适当的能源资源是能源工业决策的核心挑战之一。在本文中,考虑到技术、经济、环境和社会因素,我们讨论了突尼斯发电的一些可再生能源选择,即太阳能光伏发电(PV)、聚光太阳能发电(solar CSP)、陆上风能和生物质能。本研究采用混合多准则决策方法,将标准间相关性重要性(critical)和平均解决方案距离评价(EDAS)相结合,根据所提出的模型对考虑的备选ret进行排序和优先级排序。结果表明,太阳能光伏是突尼斯最有前途的可再生能源技术。生物质是最不可行的选择。通过蒙特卡罗模拟(MCS)验证在很大程度上证实了这些结果,始终将太阳能光伏排在第一位,其次是陆上风能。观察到的唯一微小差异是生物质和太阳能光热之间的排名交换。我们进行了敏感性分析来验证结果,并展示了改变输入数据对最终结果的影响,揭示了与成本相关的因素对几乎所有可再生能源技术的巨大影响。敏感性的关键差异是明显的,太阳能光伏对电力成本比资本成本更敏感,而太阳能光热对两者都同样重要。这些区别意味着决策和风险优先次序必须针对每个具体的RET进行调整,优先考虑降低成本和高度成本敏感技术的规模经济的研发,以及对效率敏感的技术创新和操作优化。
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引用次数: 0
Enhanced maximum power point tracking performance for PV systems in zero-energy buildings: An optimized SVR–TPE approach with hybrid energy storage and real-time capability 零能耗建筑中PV系统的增强最大功率点跟踪性能:具有混合储能和实时能力的优化SVR-TPE方法
IF 4.6 Pub Date : 2026-01-16 DOI: 10.1016/j.uncres.2026.100310
Mohammad Chegeni, Mohammad Tolou Askari, Meysam Amirahmadi, Vahid Ghods
Grid-connected photovoltaic systems used in zero-energy building applications are reliable and practically deployable only when maximum power extraction, direct-current link stability, and grid power-injection control are designed and evaluated in a coordinated, cascaded manner. This study presents an integrated three-stage framework. In the first stage, maximum power point tracking is performed using a data-driven support vector regression approach, with automatic hyperparameter tuning via a tree-structured Parzen estimator. The second stage addresses power smoothing and direct-current link stabilization through a hybrid energy storage system composed of a battery and a supercapacitor, together with a two-layer control strategy for intelligent current sharing. At this stage, the impact of tracker model selection on direct-current link voltage stability is analyzed directly, demonstrating that evaluating maximum power point tracking without considering its implications for the direct-current link and the storage subsystem can lead to a misleading assessment of true system performance. In the third stage, power conversion and bidirectional exchange with the grid are ensured by a single-phase inverter equipped with a third-order filter and a modified synchronous reference frame transformation-based control scheme. Simulation results indicate that co-design of the three stages simultaneously improves renewable energy harvesting, reduces direct-current link oscillations and battery transient stresses, and enables grid-compliant power injection and stable power exchange under zero-energy building operating scenarios.
只有以协调、级联的方式设计和评估最大功率提取、直流链路稳定性和电网功率注入控制,零能耗建筑应用中使用的并网光伏系统才可靠和实际可部署。本研究提出了一个完整的三阶段框架。在第一阶段,使用数据驱动的支持向量回归方法进行最大功率点跟踪,并通过树结构Parzen估计器进行自动超参数调整。第二阶段通过由电池和超级电容器组成的混合储能系统解决电力平滑和直流链路稳定问题,以及智能电流共享的两层控制策略。在此阶段,直接分析了跟踪器模型选择对直流链路电压稳定性的影响,表明评估最大功率点跟踪而不考虑其对直流链路和存储子系统的影响可能导致对系统真实性能的误导性评估。第三阶段采用带三阶滤波器的单相逆变器和改进的同步参考系变换控制方案,实现与电网的功率转换和双向交换。仿真结果表明,三个阶段的协同设计同时提高了可再生能源的收集,降低了直流链路振荡和电池瞬态应力,实现了零能耗建筑运行场景下电网兼容的电力注入和稳定的电力交换。
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引用次数: 0
Clustering analysis of nanoindentation data for shale: Curve-based versus mechanical parameter-based approaches 页岩纳米压痕数据的聚类分析:基于曲线的方法与基于力学参数的方法
IF 4.6 Pub Date : 2026-01-16 DOI: 10.1016/j.uncres.2026.100323
Peilin Zhang , Kouqi Liu , Zhenlin Wang , Kai Feng , Zhichao Wang , Yamin Wang , Mehdi Ostadhassan
Clustering analysis of nanoindentation data is generally done to distinguish the mechanical phases and quantitatively obtain their related mechanical properties and fractions in the entire sample. Clustering analysis is carried out based on the mechanical parameters (Young's modulus and hardness) that are obtained from the load–displacement curves of each indent. However, the accuracy of this method and its suitability for the analysis of grid nanoindentation data on a heterogeneous composite material like shale is still unknown. Therefore, this study applied clustering analysis directly on the load–displacement curves in a shale sample for the first time and compared the results with the widely used mechanical parameter-based clustering analysis method. The results showed that the mechanical parameter-based clustering distinguished four mechanical phases with 8.62, 16.07, 24.31, and 37.16 GPa as the average Young's moduli, and hardness values of 0.15, 0.35, 0.80, and 2.56 GPa, respectively. The fractions of these phases are 34.22 %, 27.78 %, 20.89 %, and 7.11 %, respectively. Likewise, the curve clustering method also distinguished four mechanical phases with Young's moduli of 4.75, 7.91, 14.10, and 22.49 GPa, and hardness values of 0.03, 0.08, 0.23, and 0.97 GPa, with fractions of 2.67 %, 12.89 %, 40.44 %, and 44.00 %, respectively. Comparing the results with the sample's mineralogy suggests that parameter-based clustering provides a better distinction between mechanical phases, closely aligning with the mineral fractions obtained from X-ray diffraction (XRD) analysis. Therefore, this approach is recommended for analyzing grid nanoindentation data in composite materials.
对纳米压痕数据进行聚类分析,通常是为了区分力学相,定量地获得它们在整个样品中的相关力学性能和分数。根据每个压痕的载荷-位移曲线获得的力学参数(杨氏模量和硬度)进行聚类分析。然而,该方法的准确性及其对非均质复合材料(如页岩)上网格纳米压痕数据分析的适用性仍然未知。因此,本研究首次将聚类分析直接应用于页岩样品的载荷-位移曲线,并将结果与广泛使用的基于力学参数的聚类分析方法进行比较。结果表明:基于力学参数的聚类可区分出4个力学相,平均杨氏模量分别为8.62、16.07、24.31和37.16 GPa,硬度值分别为0.15、0.35、0.80和2.56 GPa。这些相的含量分别为34.22%、27.78%、20.89%和7.11%。同样,曲线聚类方法也区分出杨氏模量分别为4.75、7.91、14.10和22.49 GPa,硬度值分别为0.03、0.08、0.23和0.97 GPa的4种力学相,分数分别为2.67%、12.89%、40.44%和44.00 %。将结果与样品的矿物学进行比较表明,基于参数的聚类可以更好地区分机械相,与x射线衍射(XRD)分析获得的矿物组分密切一致。因此,该方法被推荐用于分析复合材料中的网格纳米压痕数据。
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引用次数: 0
A novel method for risk identification and quantitative assessment in shale gas development phase based on STPA-FTA-DEMATEL 基于STPA-FTA-DEMATEL的页岩气开发阶段风险识别与定量评估新方法
IF 4.6 Pub Date : 2026-01-14 DOI: 10.1016/j.uncres.2025.100301
Zhicheng Zhou, Haoyu Mao, Boxun Yang, Shaoxuan Sun
With the growing strategic importance of shale gas in China's energy portfolio, effective risk assessment during the production phase has become crucial. Conventional risk analysis approaches often struggle to capture the in herent complexity and diversity of shale gas well production systems. To address this limitation, this study proposes a hybrid framework combining integrates the System-Theoretic Process Analysis (STPA), Fault Tree Analysis (FTA), and the Decision-Making Trial and Evaluation Laboratory (DEMATEL) methods to contruct a comprehensive risk assessment framework for shale gas well production. Through STPA and FTA, the study investigates four dimensions—human factors, equipment, materials, and environment—to accurately identify potential risks such as frontline operator errors, equipment failures, material supply and quality issues, and complex geological and climatic conditions. DEMATEL is subsequently employed to quantify the weights of risk factors, highlighting high-weight risks such as gas production equipment failures, gathering and transportation pipeline system failures, geological risks increasing extraction difficulty, and climatic and environmental risks that complicate extraction processes. These risks are interdependent and manifest across multiple production stages, significantly impacting the safety, stability, and efficiency of shale gas production. This research provides a more precise and comprehensive basis for shale gas production risk assessment contributing to the safe and efficient production of shale gas.
随着页岩气在中国能源组合中的战略重要性日益提高,在生产阶段进行有效的风险评估变得至关重要。传统的风险分析方法往往难以捕捉页岩气井生产系统的内在复杂性和多样性。为了解决这一局限性,本研究提出了一种混合框架,将系统理论过程分析(STPA)、故障树分析(FTA)和决策试验与评价实验室(DEMATEL)方法相结合,构建了页岩气井生产综合风险评估框架。通过STPA和FTA,该研究调查了人为因素、设备、材料和环境四个维度,以准确识别潜在风险,如一线操作人员错误、设备故障、材料供应和质量问题以及复杂的地质和气候条件。DEMATEL随后用于量化风险因素的权重,突出显示高权重风险,如天然气生产设备故障、集输管道系统故障、增加开采难度的地质风险,以及使开采过程复杂化的气候和环境风险。这些风险是相互依存的,并在多个生产阶段表现出来,严重影响页岩气生产的安全性、稳定性和效率。该研究为页岩气生产风险评估提供了更加准确、全面的依据,有助于页岩气的安全高效生产。
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引用次数: 0
Resilient control of AC microgrids via MSOGI-FLL and virtual complex impedance 基于MSOGI-FLL和虚拟复阻抗的交流微电网弹性控制
IF 4.6 Pub Date : 2026-01-14 DOI: 10.1016/j.uncres.2026.100321
Mohamed Said Adouairi , Saad Motahhir , Badre Bossoufi
This paper presents a novel and resilient control strategy for isolated AC microgrids based on a Multiple Second-Order Generalized Integrator with Frequency-Locked Loop architecture and a complex virtual impedance design. The proposed method addresses key challenges associated with power sharing accuracy, harmonic distortion, and system robustness in the presence of nonlinear loads, frequency variation, and complex inverter-to-load impedance characteristics. The main innovation lies in the integration of multi-harmonic Multiple Second-Order Generalized Integrator with Frequency-Locked Loop signal decomposition with adaptive complex virtual impedance and coordinated droop-based control, providing improved harmonic suppression, precise power sharing, and enhanced transient stability compared to existing approaches. A novel signal conditioning scheme based on Multiple Second-Order Generalized Integrator with Frequency-Locked Loop is employed to extract fundamental and selected harmonic components of inverter currents while rejecting DC offsets. The extracted signals are used to synthesize an adaptive virtual complex impedance that enhances droop-based power sharing under coupled resistive-inductive line conditions. To accurately assess system dynamics, a linear time-periodic model is developed for the Multiple Second-Order Generalized Integrator with Frequency-Locked Loop, enabling the derivation of harmonic transfer functions and stability margins. The control strategy is further augmented by a coordinated Battery Management System, ensuring energy balance and flexibility in transient scenarios. Simulation results involving three parallel single-phase inverters confirm the proposed method's ability to achieve accurate active and reactive power sharing, minimize circulating currents, and maintain robust performance under distorted and unbalanced operating conditions. The effectiveness of the proposed control is validated through detailed comparisons with conventional droop methods.
本文提出了一种基于锁频环结构的多重二阶广义积分器和复杂虚拟阻抗设计的隔离型交流微电网弹性控制策略。提出的方法解决了在非线性负载、频率变化和复杂的逆变器负载阻抗特性存在的情况下与功率共享精度、谐波失真和系统鲁棒性相关的关键挑战。主要创新点在于将多谐波多重二阶广义积分器与锁频环信号分解、自适应复杂虚拟阻抗和基于垂降的协调控制相结合,与现有方法相比,提供了更好的谐波抑制、精确的功率共享和增强的暂态稳定性。提出了一种基于锁频环多重二阶广义积分器的信号调理方案,在抑制直流偏置的同时提取逆变器电流的基频分量和谐波分量。提取的信号用于合成自适应虚拟复阻抗,增强了电阻-电感耦合条件下基于下垂的功率共享。为了准确地评估系统动力学,建立了多二阶锁频环广义积分器的线性时间周期模型,从而推导出谐波传递函数和稳定裕度。通过协调的电池管理系统进一步增强了控制策略,确保了瞬态情况下的能量平衡和灵活性。对三个并联单相逆变器的仿真结果证实了该方法能够实现准确的有功和无功共享,最小化循环电流,并在畸变和不平衡运行条件下保持稳健的性能。通过与常规下垂方法的详细比较,验证了所提控制方法的有效性。
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引用次数: 0
Real time implementation for robust adaptive sliding mode predictive control of PMSM 永磁同步电机鲁棒自适应滑模预测控制的实时实现
IF 4.6 Pub Date : 2026-01-02 DOI: 10.1016/j.uncres.2026.100304
Rachid Ibrahimi , Mohamed said Adouairi , Abdennabi Morchid , Badre Bossoufi , Paweł Skruch , Saleh Mobayen
Model Predictive Control is recognized as a promising approach for electric drives, with particular interest in the development of robust and high-performance predictive models. In this work, we propose an Adaptive Integral Sliding Mode Predictive Control for Permanent Magnet Synchronous Motors, combining a predictive model with an adaptive law based on the integral sliding mode. This method automatically adjusts the sliding function limit, reducing the chattering phenomenon while enhancing the system dynamics.
To ensure compatibility with industrial electronic boards, the Adaptive Integral Sliding Mode Predictive Control was implemented following the V-cycle development process, including Model-in-the-Loop, Software-in-the-Loop, and Processor-in-the-Loop validation. This framework facilitates the deployment of embedded control software in the automotive sector and provides a cost-effective evaluation of the hardware implementation.
Furthermore, real-time simulations of control, Invariant Sliding Mode Predictive Control, and Sliding Mode Control configurations were carried out on the dSPACE DS1104 platform, showing excellent correlation with MATLAB/Simulink results. Experimental validation on the STM32F4 board confirms that the proposed approach offers faster response to load torque disturbances and better performance over a wide speed range, demonstrating its reliability, robustness, and effectiveness.
模型预测控制被认为是一种很有前途的电力驱动方法,特别是对鲁棒和高性能预测模型的开发。在这项工作中,我们提出了一种永磁同步电机的自适应积分滑模预测控制,将预测模型与基于积分滑模的自适应律相结合。该方法自动调节滑动函数极限,在增强系统动力学的同时减少了抖振现象。为了确保与工业电子电路板的兼容性,自适应积分滑模预测控制遵循v周期开发过程,包括模型在环、软件在环和处理器在环验证。该框架促进了嵌入式控制软件在汽车领域的部署,并提供了对硬件实现的成本效益评估。此外,在dSPACE DS1104平台上对控制、不变滑模预测控制和滑模控制配置进行了实时仿真,结果与MATLAB/Simulink的结果具有良好的相关性。在STM32F4板上的实验验证证实了所提出的方法对负载扭矩干扰的响应速度更快,并且在较宽的速度范围内具有更好的性能,证明了其可靠性,鲁棒性和有效性。
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引用次数: 0
Modeling and simulation of hybrid fuzzy-PID and model predictive control for enhanced dual-axis photovoltaic tracking precision 提高双轴光伏跟踪精度的模糊pid与模型预测混合控制建模与仿真
IF 4.6 Pub Date : 2026-01-01 DOI: 10.1016/j.uncres.2025.100303
Rezi Delfianti , Mohammed Mareai , Federico Minelli , Catur Harsito , Fauzan Nusyura
This paper presents a comprehensive evaluation of several control strategies for dual-axis solar tracking systems, including proportional–integral–derivative, fuzzy logic, fuzzy–PID, and fuzzy–PID enhanced with model predictive control. Each controller was implemented in MATLAB/Simulink to analyse its dynamic and steady-state behaviour under identical conditions. The findings reveal that hybrid and MPC-based controllers achieve superior tracking precision and response smoothness compared to single-loop designs. Specifically, the fuzzy-tuned PID exhibits the fastest rise time of 12.53 ms but with a higher overshoot of 18.45 %. In contrast, the standalone fuzzy controller offers superior stability with a minimal overshoot of 0.50 %, though at the expense of slower dynamics with a rise time of 91.81 ms. The proposed MPC–Fuzzy–PID Series hybrid achieves a rapid rise time of 16.02 ms and a settling time of 0.2 s, providing a balanced trade-off between speed, stability, and computational efficiency, making it suitable for real-time solar tracking applications. Overall, the study demonstrates that controller performance depends on the specific operational goals whether prioritizing rapid response, precision, or robustness highlighting the importance of adaptive hybrid control design in sustainable energy systems.
本文综合评价了双轴太阳跟踪系统的几种控制策略,包括比例-积分-导数、模糊逻辑、模糊pid和模型预测控制增强的模糊pid。每个控制器在MATLAB/Simulink中实现,分析其在相同条件下的动态和稳态行为。研究结果表明,与单回路设计相比,混合和基于mpc的控制器具有更高的跟踪精度和响应平稳性。具体而言,模糊调谐PID的上升时间最快,为12.53 ms,但超调量较高,为18.45%。相比之下,独立模糊控制器提供了卓越的稳定性,最小超调为0.50%,但代价是较慢的动态,上升时间为91.81 ms。所提出的MPC-Fuzzy-PID系列混合实现了16.02 ms的快速上升时间和0.2 s的沉降时间,在速度,稳定性和计算效率之间提供了平衡的权衡,使其适合实时太阳跟踪应用。总体而言,该研究表明,控制器的性能取决于具体的操作目标,是否优先考虑快速响应、精度或鲁棒性,这突出了自适应混合控制设计在可持续能源系统中的重要性。
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引用次数: 0
Modeling geothermal reservoirs permeability based upon NMR laboratory data 基于核磁共振实验室数据的地热储层渗透率建模
IF 4.6 Pub Date : 2026-01-01 DOI: 10.1016/j.uncres.2026.100307
Kusum Yadav , Lulwah M. Alkwai , Shahad Almansour , Debashis K. Dutta , Ahmad Adel Abu-Shareha , Mehrdad Mottaghi
Accurate permeability characterization is crucial for the efficient and sustainable development of geothermal resources. However, conventional methods like well testing and core analysis are often expensive and fail to capture the complex, heterogeneous nature of geothermal reservoirs. While Nuclear Magnetic Resonance (NMR) logging provides valuable insights into pore structure, its traditional permeability models are often unreliable in high-temperature, high-salinity geothermal environments. A novel data-driven methodology is introduced for modeling permeability in geothermal reservoirs by integrating Nuclear Magnetic Resonance (NMR) laboratory measurements with advanced machine learning algorithms. The approach employs a curated dataset of geothermal core samples, utilizing porosity, logarithmic mean transverse relaxation time (T2lm), and mode transverse relaxation time (T2mode) as predictive features across multiple learning models. Outlier detection was conducted using the Leverage technique, while model reliability was validated through K-fold cross-validation. Among the tested algorithms, the Decision Tree model demonstrated superior performance, yielding the highest coefficient of determination (R2) and the lowest error metrics. Sensitivity analysis further revealed porosity as the most dominant factor influencing geothermal permeability. The findings validate the utility of using ensemble soft computing to boost the accuracy of permeability prediction, presenting a valuable and affordable alternative to traditional techniques. Our findings bridge the gap between core analysis and computational modeling, paving the way for more accurate geothermal reservoir characterization and optimization.
准确的渗透率表征对地热资源的高效可持续开发至关重要。然而,常规的方法,如试井和岩心分析,往往是昂贵的,并且无法捕捉到地热储层的复杂性和非均质性。虽然核磁共振(NMR)测井提供了宝贵的孔隙结构信息,但其传统渗透率模型在高温、高盐度地热环境中往往不可靠。引入了一种新的数据驱动方法,通过将核磁共振(NMR)实验室测量与先进的机器学习算法相结合,来模拟地热储层的渗透率。该方法采用地热岩心样本的精心整理的数据集,利用孔隙度、对数平均横向松弛时间(T2lm)和模式横向松弛时间(T2mode)作为多个学习模型的预测特征。采用杠杆技术进行离群值检测,通过K-fold交叉验证验证模型的可靠性。在测试的算法中,决策树模型表现出优异的性能,产生最高的决定系数(R2)和最低的误差指标。敏感性分析进一步揭示孔隙度是影响渗透率的最主要因素。研究结果验证了使用集成软计算提高渗透率预测准确性的实用性,为传统技术提供了一种有价值且经济实惠的替代方案。我们的发现弥补了岩心分析和计算建模之间的差距,为更准确地表征和优化地热储层铺平了道路。
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Unconventional Resources
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