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基于Point-Attention点云分类的激光雷达故障诊断方法研究
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作者 谭光兴 程星 陈海峰 《现代电子技术》 北大核心 2025年第20期10-17,共8页
在智能车辆和自主机器人领域,激光雷达传感器因高精度和可靠性,被广泛应用于环境感知和物体检测,因此其故障诊断尤为重要。激光雷达内部的故障往往有固件提醒,而外部环境因素导致的故障检测挑战较大,比如车辆形变、污垢等导致的激光点... 在智能车辆和自主机器人领域,激光雷达传感器因高精度和可靠性,被广泛应用于环境感知和物体检测,因此其故障诊断尤为重要。激光雷达内部的故障往往有固件提醒,而外部环境因素导致的故障检测挑战较大,比如车辆形变、污垢等导致的激光点云遮挡故障,难以直接在固件层面体现,需通过外部检测进行诊断。为此,提出一种基于Point-Attention激光雷达遮挡故障诊断方法。首先,结合多头几何注意力机制模块与CBAM模块、残差连接机制,增强了模型对点云数据中关键特征的提取能力,提高了分类准确性和鲁棒性;在真实的ScanObjectNN数据集和ModelNet40基准数据集上对Point-Attention模型进行了实验。该模型在分类任务上准确率分别达到了93.7%、82.5%。其次,融合了一种时间特征捕捉机制,从而使模型能够更好地适应现实场景中的时间相关性,进而更准确地处理激光雷达的遮挡故障。实验结果表明,所提方法能有效诊断激光雷达遮挡故障,最佳总体精度达99%以上,为激光雷达故障诊断提供了一种高效准确的解决方案。 展开更多
关键词 激光雷达 故障诊断 点云分类 残差连接 遮挡检测 时间特征捕捉
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Selection of Minimal Test Points Set for Integer-Coded Fault Wise Table 被引量:1
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作者 Shu-Lin Tian Cheng-Lin Yang Bing Long 《Journal of Electronic Science and Technology of China》 2009年第4期312-316,共5页
Test points selection for integer-coded fault wise table is a discrete optimization problem. On one hand, traditional exhaustive search method is computationally expensive. On the other hand, the space complexity of t... Test points selection for integer-coded fault wise table is a discrete optimization problem. On one hand, traditional exhaustive search method is computationally expensive. On the other hand, the space complexity of traditional exhaustive is low. A tradeoff method between the high time complexity and low space complexity is proposed. At first, a new fault-pair table is constructed based on the integer-coded fault wise table. The fault-pair table consists of two columns: one column represents fault pair and the other represents test points set that can distinguish the corresponding faults. Then, the rows are arranged in ascending order according to the cardinality of corresponding test points set. Thirdly, test points in the top rows are selected one by one until all fault pair are isolated. During the test points selection process, the rows that contain selected test points are deleted and then the dimension of fault-pair table decreases gradually. The proposed test points selection algorithm is illustrated and tested using an integercoded fault wise table derived from a real analog circuit. Computational results suggest show policies are better than the exhaustive strategy. 展开更多
关键词 fault-pair table integer-coded fault wise table optimization test points selection.
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Application of Rollout Strategy to Test Points Selection for Integer-Coded Fault Wise Table 被引量:4
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作者 Cheng-Lin Yang Shu-Lin Tian Bing Long 《Journal of Electronic Science and Technology of China》 2009年第4期308-311,共4页
Test points selection for integer-coded fault wise table is a discrete optimization problem. The global minimum set of test points can only be guaranteed by an exhaustive search which is eompurationally expensive. In ... Test points selection for integer-coded fault wise table is a discrete optimization problem. The global minimum set of test points can only be guaranteed by an exhaustive search which is eompurationally expensive. In this paper, this problem is formulated as a heuristic depth-first graph search problem at first. The graph node expanding method and rules are given. Then, rollout strategies are applied, which can be combined with the heuristic graph search algorithms, in a computationally more efficient manner than the optimal strategies, to obtain solutions superior to those using the greedy heuristic algorithms. The proposed rollout-based test points selection algorithm is illustrated and tested using an analog circuit and a set of simulated integer-coded fault wise tables. Computa- tional results are shown, which suggest that the rollout strategy policies are significantly better than other strategies. 展开更多
关键词 Heuristic graph search integer-coded fault wise table optimization rollout strategy test points selection.
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基于XGBoost建模和Change-Point残差处理的风电机组齿轮箱温度预警 被引量:9
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作者 王桂松 郭鹏 +2 位作者 胥佳 刘瑞华 李韶武 《电力科学与工程》 2018年第9期46-53,共8页
风电机组具有单机容量小,台数多,状态信息复杂的特点;基于SCADA数据的风电机组齿轮箱预警普遍存在预测精度和计算效率低,资源占用高的问题,选取有效方法以克服上述问题成为齿轮箱预警的关键。极限梯度提升(eXtreme Gradient Boosting,XG... 风电机组具有单机容量小,台数多,状态信息复杂的特点;基于SCADA数据的风电机组齿轮箱预警普遍存在预测精度和计算效率低,资源占用高的问题,选取有效方法以克服上述问题成为齿轮箱预警的关键。极限梯度提升(eXtreme Gradient Boosting,XGBoost)算法本身结合多线程、数据压缩、分片的形式,其在处理大数据量样本时仍具有较高的通用性。采用XGBoost算法建立齿轮箱正常工作状态的温度模型,使用XGBoost模型与其它4类回归预测模型分别进行齿轮箱温度预测模型实验,结果表明XGBoost模型在齿轮箱温度预测中综合性能要优于其它4类模型。当齿轮箱发生故障时,模型的样本特性会发生异常变化,导致模型的预测残差发生明显改变。为提高齿轮箱故障预警的可靠性,构建了新的Change-Point算法,利用Change-Point技术进行XGBoost模型预测残差序列分析,可定位齿轮箱状态劣化时间点,回溯状态劣化原因。 展开更多
关键词 XGBoost 齿轮箱 预警 CHANGE-point 残差序列
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Discrete Software Reliability Growth Modeling for Errors of Different Severity Incorporating Change-point Concept 被引量:4
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作者 D.N.Goswami Sunil K.Khatri Reecha Kapur 《International Journal of Automation and computing》 EI 2007年第4期396-405,共10页
Several software reliability growth models (SRGM) have been developed to monitor the reliability growth during the testing phase of software development. In most of the existing research available in the literatures... Several software reliability growth models (SRGM) have been developed to monitor the reliability growth during the testing phase of software development. In most of the existing research available in the literatures, it is considered that a similar testing effort is required on each debugging effort. However, in practice, different types of faults may require different amounts of testing efforts for their detection and removal. Consequently, faults are classified into three categories on the basis of severity: simple, hard and complex. This categorization may be extended to r type of faults on the basis of severity. Although some existing research in the literatures has incorporated this concept that fault removal rate (FRR) is different for different types of faults, they assume that the FRR remains constant during the overall testing period. On the contrary, it has been observed that as testing progresses, FRR changes due to changing testing strategy, skill, environment and personnel resources. In this paper, a general discrete SRGM is proposed for errors of different severity in software systems using the change-point concept. Then, the models are formulated for two particular environments. The models were validated on two real-life data sets. The results show better fit and wider applicability of the proposed models as to different types of failure datasets. 展开更多
关键词 Discrete software reliability growth model non-homogeneous Poisson process fault severity change point probability generating function.
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Comprehensive Multi-Level Exploration of Buried Active Faults:an Example of the Yinchuan Buried Active Fault 被引量:1
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作者 Chai Chizhang Meng Guangkui +9 位作者 Du Peng Wang Yin Liu Baojin Shen Weihua LeiQiyun Liao Yuhua Zhao Chengbin Feng Shaoying Zhang Xuehui Xie Xiaofeng 《Earthquake Research in China》 2007年第3期225-235,共11页
The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based... The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based on the comprehensive analyses of previous data, we choose the Xinqushao Village of Xingqing District of Yinchuan City as the test site for the comprehensive exploration. Firstly, we adopted shallow seismic investigation with group intervals of 10m, 5m and lm to gradually trace layer by layer the master fault of the Yinchuan buried fault from a deep depth to a shallow depth where drilling could be used. Then, with composite geological profile drilling, we determined the precise location and dip angle of the fault. The drilling show the buried depth of the upper offset point is 8.3m. Finally, large-scale trenching revealed that the actual buried depth of the upper offset point of the fault is 1.5m from the ground surface and there are paleoearthquake events of 5 stages. Combined with the preliminary result of corresponding sample age, we conclude the Yinchuan buried fault is a mid to late Holocene active fault. 展开更多
关键词 Buried active fault Comprehensive test exploration The upper offset point of fault Yinchuan
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K-means聚类精简点云驱动PointNet++的行星齿轮故障诊断 被引量:4
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作者 万卓 孙显彬 +1 位作者 申玉杰 董美琪 《组合机床与自动化加工技术》 北大核心 2023年第11期84-88,共5页
复杂装备的三维模型点云数据具有非结构化、无序性、离散性的特点,数据精简策略和深度神经网络模型构建被视为点云数据驱动的机械设备故障诊断关键技术难点。提出了一种K-means聚类(K均值聚类算法)精简点云驱动PointNet++的行星齿轮故... 复杂装备的三维模型点云数据具有非结构化、无序性、离散性的特点,数据精简策略和深度神经网络模型构建被视为点云数据驱动的机械设备故障诊断关键技术难点。提出了一种K-means聚类(K均值聚类算法)精简点云驱动PointNet++的行星齿轮故障诊断方法。首先,提出了基于K-means的点云数据精简策略实现了在充分保留细节特征的前提下,精简84%的冗余数据;其次,构建了简度、速度、精度的精简效果三维评价指标体系并对精简算法进行评价;最后,构建了能够提取局部特征的PointNet++故障诊断模型。实验结果表明,相比于点云数据直接驱动PointNet++,K-means聚类精简点云驱动PointNet++的行星齿轮故障诊断的准确率提升了6.9%,表明了所提方法的有效性。 展开更多
关键词 行星齿轮 点云数据 故障诊断 二分K-means聚类 pointNet++
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The Comprehensive Evaluation Algorithm with Fault Location in HVDC Transmission Line
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作者 Zhenquan Sun Qiyue Huang +5 位作者 Changjin Hu Xiaoning Kang Hao Wang Xuze Zhang Chong Zhao Yali Ma 《Energy and Power Engineering》 2017年第4期30-35,共6页
China has a vast territory with a great demand for electricity. However, the resources are in reverse distribution in the country. Therefore, high voltage direct current transmission has great practical significance a... China has a vast territory with a great demand for electricity. However, the resources are in reverse distribution in the country. Therefore, high voltage direct current transmission has great practical significance and been widely used. However, traditional fault location methods have a lot of problems in engineering application for the length of transmission line and the complexity of the terrain. This paper proposes a comprehensive evaluation algorithm based on the travelling wave method and time domain method. It also proposes a concept of fault point reliability. This algorithm analyzes the fault point reliability in the whole transmission line to determine the specific location of the fault point. This paper proves that the algorithm has high reliability by PSCAD simulation software. 展开更多
关键词 COMPREHENSIVE Evaluation Algorithm TRAVELLING Wave METHOD TIME-DOMAIN METHOD fault LOCATION fault point Reliability
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Vertical dominant migration channel and hydrocarbon migration in complex fault zone, Bohai Bay sag, China 被引量:1
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作者 XU Changgui PENG Jingsong +2 位作者 WU Qingxun SUN Zhe YE Tao 《Petroleum Exploration and Development》 2019年第4期720-728,共9页
The quantitatively/semi-quantitatively formation conditions of vertical dominant hydrocarbon migration pathways were analyzed based on the big data analysis of petroleum geological parameters of complex fault Zone zon... The quantitatively/semi-quantitatively formation conditions of vertical dominant hydrocarbon migration pathways were analyzed based on the big data analysis of petroleum geological parameters of complex fault Zone zone in the central-south Bohai Bay. According to this condition, the vertical dominant migration pathway and its charge points/segments are searched through structural modeling assistant analysis in the East Sag of Huanghekou. Under the constraints of charge points/segments, numerical simulation of hydrocarbon charge and migration is carried out to successfully predict hydrocarbon migration pathways and hydrocarbon enrichment blocks in shallow layers of complex fault zone. The main results are as follows:(1) The hydrocarbon charge in shallow layers of the active fault zone is differential, the charge points/sections of vertical dominant migration pathways are the starting points of shallow hydrocarbon migration and are very important for the hydrocarbon migration and accumulation in the shallow layers.(2) Among the shallow faults, those cutting the deep transfer bins or deep major migration pathways, with fault throw of more than 80 m in the accumulation period and the juxtaposition thickness between fault and caprock of the deep layers of less than 400 m are likely to be vertical dominant migration pathways in the sag area.(3) By controlling the vertical dominant migration pathways and charging points/segments in carrier layer, Neo-tectonic movement caused the differential hydrocarbon accumulation in the complex fault zone. The research results are of great significance for the fine exploration of the complex fault zone. 展开更多
关键词 offshore Bohai Bay Basin SAG area VERTICAL DOMINANT MIGRATION pathway COMPLEX fault zone charge points NEOTECTONIC movement big data analysis
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钻孔联合地质剖面探测施工中若干问题探讨 被引量:1
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作者 贺为民 《地球与行星物理论评(中英文)》 2025年第2期157-166,共10页
基于《活动断层探测》GB/T 36072—2018、《活动断层探查钻探》DB/T 92—2022等现行规范规程,对跨隐伏活动断层的钻孔联合地质剖面探测施工的基本要求和存在的主要问题进行了探讨,认为现行技术标准存在的问题有:(1)对岩芯采取率的要求偏... 基于《活动断层探测》GB/T 36072—2018、《活动断层探查钻探》DB/T 92—2022等现行规范规程,对跨隐伏活动断层的钻孔联合地质剖面探测施工的基本要求和存在的主要问题进行了探讨,认为现行技术标准存在的问题有:(1)对岩芯采取率的要求偏低;(2)对横跨隐伏逆断层的钻孔深度和钻孔之间距离的要求偏低.提出了下列改进措施:(1)各类岩土的岩芯采取率应大于现行技术标准要求的数值;其中,黏土的岩芯采取率应不小于99%;(2)对横跨隐伏逆断层的钻孔深度应大于现行技术标准要求的孔深;在第四系厚度较薄时,在逆断层上断点附近,位于逆断层上盘的钻孔在钻遇上盘的前第四系后,还应继续钻进,钻孔深度应达到能够揭露逆断层下盘的前第四系的深度;(3)当隐伏逆断层在第四系中的断距较小时,逆断层上断点两侧的2个相邻钻孔间距就需要1~3 m甚至更小的数值.补充了钻孔联合地质剖面探测中的钻孔布设方式、隐伏断层产状的求取方法.分析了在钻孔联合地质剖面探测的断层识别中存在的一些不确定性因素,并提出了相应对策.指出钻孔联合地质剖面探测施工是基于动态设计的信息化施工,现场技术负责人及其施工现场技术管理在钻孔联合地质剖面探测工作中起着重要作用. 展开更多
关键词 活动断层 钻孔联合地质剖面 断层活动性鉴定 断层上断点 岩芯采取率
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基于受扰后平衡点延拓的在线暂态稳定控制策略——受扰后平衡点计算
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作者 李崇涛 张建新 +4 位作者 何劲捷 刘宇明 李诗旸 高琴 段超 《西安交通大学学报》 北大核心 2025年第9期11-21,32,共12页
针对传统潮流计算模型在电力系统受扰后平衡点计算中的局限性,提出一种考虑动态元件稳态运行特性的受扰后系统平衡点计算方法。首先,从代数方程角度出发,构建了包含电源、负荷及网络的受扰后平衡点分析模型;之后,基于同伦法给出了受扰... 针对传统潮流计算模型在电力系统受扰后平衡点计算中的局限性,提出一种考虑动态元件稳态运行特性的受扰后系统平衡点计算方法。首先,从代数方程角度出发,构建了包含电源、负荷及网络的受扰后平衡点分析模型;之后,基于同伦法给出了受扰后系统平衡点的高效求解步骤,解决了严重扰动下牛顿法收敛困难的问题;最后,采用IEEE 39节点标准算例及省级实际电网算例验证了所提方法。结果表明:所建模型适用于包括新能源在内的动态元件,具有较强的通用性;所提计算方法与暂态仿真计算方法的收敛结果完全相符,且收敛耗时减少了95%以上,准确性相比传统的潮流方法提高了至少3个数量级,为受扰后系统的快速在线稳定性评估提供了高效解析工具。 展开更多
关键词 电力系统 受扰后平衡点 暂态稳定 同伦法
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基于波形相似性的柔性互联配电网短路故障区段定位方法 被引量:2
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作者 陈继明 陈文淙 +2 位作者 仉志华 于馨玮 徐乾 《电力工程技术》 北大核心 2025年第1期104-114,共11页
由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段... 由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。 展开更多
关键词 柔性互联配电网(FDN) 柔性多状态开关(SNOP) 故障分析 波形相似性 故障定位 电流正序分量
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基于多策略融合的光伏系统故障诊断方法
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作者 李斌 王于绰 《系统仿真学报》 北大核心 2025年第12期3018-3032,共15页
为解决光伏系统故障频发的问题,提出一种基于改进旅鼠算法优化多模态融合故障诊断模型。通过马尔可夫转换场将光伏电流、电压一维时序信号转换为二维图像,利用多尺度卷积神经网络挖掘原始波形的空间特征;采用BiGRU提取原始波形的时序动... 为解决光伏系统故障频发的问题,提出一种基于改进旅鼠算法优化多模态融合故障诊断模型。通过马尔可夫转换场将光伏电流、电压一维时序信号转换为二维图像,利用多尺度卷积神经网络挖掘原始波形的空间特征;采用BiGRU提取原始波形的时序动态特征,通过特征融合层实现时空特征的互补增强。引入改进旅鼠算法对BiGRU隐藏层神经元数量、模型的学习率等参数进行自适应优化,结合注意力机制强化故障敏感特征的权重分配。仿真实验结果表明:所提模型仿真与实测数据的诊断准确率分别达到97.9%和95.4%,相较对比模型,诊断准确率提升最高4.1%,为光伏系统智能化运维提供了新的技术路径。 展开更多
关键词 马尔可夫场 双向门控循环单元 改进旅鼠算法 故障诊断 MPPT(maximum power point tracking)故障 逆变器故障
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Study of the Relation Between the Features of Fault Deformation Tendency Anomaly and Earthquake Activity in the West of China
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作者 Chen Bing Jiang Zaisen Zhao Zhencai 《Earthquake Research in China》 2000年第3期72-83,共12页
Using the tendentious accumulation rate of crustal deformation,DC,the spatial distributionfeatures of deformation across fault in the West of China was studied;the regional patterns ofdeformation accumulation induced ... Using the tendentious accumulation rate of crustal deformation,DC,the spatial distributionfeatures of deformation across fault in the West of China was studied;the regional patterns ofdeformation accumulation induced by fault activity was established and its seismogenicmeaning was discussed.The types of fault deformation evolution in the time domain and thefeatures of change of large extent anomaly in fault deformation which occurred in 1995~1996was analyzed comprehensively.It was indicated definitely that 1995~1996 is the turningpoint of fault network activity in the West of China since the 1990s;it is closely related to thechange of main seismic active regions in the West of China,i.e,the alternation of strong/weak stages and the change of action range of tectonic stress field in the Qinghai-Tibet blockand its environs;and hence it is of medium-and short-term precursor meaning for the changeof the overall pattern of earthquake activity in the West of China in the year 1996.On such abasis,a 展开更多
关键词 fault deformation Tendentious ACCUMULATION rate Crowd ANOMALY TURNING point
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Fold catastrophe model of strike-slip fault earthquake
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作者 潘岳 李爱武 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第3期349-362,共14页
Using a differential form of the potential energy function and taking the effect of work applied by external force in far field into account, the mechanism of strike-slip fault earthquake is analyzed. The research ind... Using a differential form of the potential energy function and taking the effect of work applied by external force in far field into account, the mechanism of strike-slip fault earthquake is analyzed. The research indicates that each characteristic displayed with a fold catastrophe model in the catastrophe theory corresPonds to a specific primary characteristic of the strike-slip fault earthquake. The fold catastrophe can describe the positions of starting and end points of a fault failure and the distance of fault dislocation. These include the description of stability of the surrounding rock-fault system before and after the earthquake. Two different illustrations about elastic energy releasing amount of the surrounding rock with the fault failure are shown with the primary characteristics mutually demonstrated. The intensity of strike-slip fault earthquake is related to the surrounding rock press and the stiffness ratio of surrounding rock and fault. The larger the surrounding rock press, the smaller the stiffness ratio. The larger the included angle between the tangential stress axis and the causative fault surface, the stronger the earthquake. 展开更多
关键词 fault earthquake fold catastrophe model end point of failure failure criterion energy import rate elastic energy releasing amount
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采用单测点电流行波的输电线路故障区段辨识与测距
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作者 张广斌 舒帮贵 +1 位作者 束洪春 司大军 《电力系统自动化》 北大核心 2025年第19期196-207,共12页
目前,输电线路所装设的沿线分布式行波测点需配对使用且仅能完成严格依赖时钟同步的多端测距,仅利用单测点行波无法独立判别区段和测距。文中提出采用单测点电流行波的输电线路故障区段辨识与测距方法。首先,分析输电线路两端多出线拓... 目前,输电线路所装设的沿线分布式行波测点需配对使用且仅能完成严格依赖时钟同步的多端测距,仅利用单测点行波无法独立判别区段和测距。文中提出采用单测点电流行波的输电线路故障区段辨识与测距方法。首先,分析输电线路两端多出线拓扑结构特点,利用其所决定的极性能够辨识沿线单测点后续电流行波的性质。进一步,基于行波进入区段后是否存在故障点反射这一故障区段与健全区段的本质差异,利用沿线测点把线路划分成两个不等长区段且测点处的波阻抗连续特点,将故障区段判定和单端测距均转化为对区段入射波和反射波间时延的检测。利用相对极性和区段固有到达时差实现波头的辨识,最终实现故障区段判定和故障测距。基于现场大量实测数据与仿真验证了所提方法的有效性,其不受故障类型、过渡电阻等因素影响,无死区且行波测点安装位置灵活。 展开更多
关键词 输电线路 行波 测点 固有时差 故障区段辨识 故障测距
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基于震前-震后高精度地形点云数据提取三维地表同震位移场信息
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作者 魏占玉 何宏林 +1 位作者 邓亚婷 席茜 《地震地质》 北大核心 2025年第1期167-188,共22页
地震破裂带附近同震位移和变形模式对于深入理解地震破裂过程、断层行为及活动断层与地形地貌关系等至关重要。文中提出一种迭代最近点(ICP)算法,利用地震前后地形点云进行差分确定断层近场三维同震地表位移。在川西大凉山断裂带交际河... 地震破裂带附近同震位移和变形模式对于深入理解地震破裂过程、断层行为及活动断层与地形地貌关系等至关重要。文中提出一种迭代最近点(ICP)算法,利用地震前后地形点云进行差分确定断层近场三维同震地表位移。在川西大凉山断裂带交际河断层上选取2期SfM地形点云叠加同震位移场模拟震前-震后点云,测试ICP方法获取同震位移场的精度。该方法在网格边长>50m的条件下可准确恢复同震位移场的方向和幅度,水平和垂直精度分别为20~10cm,这与地形点云定位精度相当。随着点云密度和网格窗口尺寸减小,该方法恢复同震位移场等的精度将降低。通过分析树木生长、房屋建设、河流侵蚀等地形变化对恢复位移场的潜在影响,研究结果表明扩大网格尺寸可使震前-震后点云具有足够地形结构进行匹配,以减小局部地形变化对恢复位移场的影响,网格窗口尺寸是在具有足够地形结构的大尺度和具有更精细分辨率的小尺度之间的权衡。文中所述的ICP方法利用震前-震后高精度点云可获取地震破裂带附近精细的三维地表位移场,为浅层断层滑动和破裂带变形提供了新的约束,有助于研究地震破裂过程和断层生长过程。 展开更多
关键词 三维同震位移场 ICP算法 地形点云 地震破裂 活动断层
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多逆变器并联系统暂态稳定性分析及其暂态电流注入策略 被引量:2
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作者 王继磊 张兴 《高电压技术》 北大核心 2025年第1期390-400,I0045,I0046,共13页
在电网故障期间,逆变器之间以及逆变器与电网之间的交互作用易引发多逆变器并联系统暂态稳定性问题。此外,以往的逆变器暂态稳定性分析结果与改进策略的研究对象大多为单逆变器并网系统,可能并不适用于多逆变器并联系统。针对这一问题,... 在电网故障期间,逆变器之间以及逆变器与电网之间的交互作用易引发多逆变器并联系统暂态稳定性问题。此外,以往的逆变器暂态稳定性分析结果与改进策略的研究对象大多为单逆变器并网系统,可能并不适用于多逆变器并联系统。针对这一问题,首先建立了多逆变器并联系统暂态同步模型,指出多机交互作用会改变系统平衡点存在性和暂态特征参数。然后,在不同电网故障初始状态和逆变器输出特性下,采用等面积准则和相平面图分析了多机交互作用对系统暂态稳定性的影响规律。基于此,提出了一种实现电网故障前后平衡点近似恒定的暂态电流注入策略,以确保各逆变器暂态稳定运行,为电网故障期间暂态电流的设置提供参考。最后,基于Matlab/Simulink仿真软件和实验平台进行了仿真和实验验证,结果表明所提暂态同步模型能够准确反映系统暂态响应特性,所提策略能够最大化系统暂态稳定裕度。 展开更多
关键词 多逆变器并联系统 暂态稳定性 多机交互作用 暂态电流注入策略 电网故障 平衡点存在性
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基于频率特征的变速抽蓄机组转子侧单相接地故障区域定位 被引量:1
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作者 邢恺 桂林 +2 位作者 张琦雪 王凯 陈龙翔 《电力系统自动化》 北大核心 2025年第13期187-194,共8页
抽水蓄能电站因其技术成熟、容量大、经济性高,已成为新型电力系统的重要调节手段。双馈变速抽蓄机组因其高效的运行性能和快速调节能力备受关注。相较于常规同步发电机,双馈变速抽蓄机组的转子绕组和励磁系统更复杂,长期运行更易出现... 抽水蓄能电站因其技术成熟、容量大、经济性高,已成为新型电力系统的重要调节手段。双馈变速抽蓄机组因其高效的运行性能和快速调节能力备受关注。相较于常规同步发电机,双馈变速抽蓄机组的转子绕组和励磁系统更复杂,长期运行更易出现单相接地故障。现有的接地故障保护方案主要针对常规定速机组,难以有效覆盖双馈变速抽蓄机组的转子绕组和励磁系统。为解决这一问题,首先,对故障区域进行划分,并进一步分析了不同区域的单相接地故障特征。然后,通过建模仿真验证了各区域的故障特征分析,并提出了基于中性点电压特征频率分量判据与接地过渡电阻判据的故障区域定位方法,为双馈变速抽蓄机组提供了一种有效的转子接地故障保护方案。 展开更多
关键词 新型电力系统 变速抽蓄机组 转子 单相接地故障 故障定位 中性点电压
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基于声音信号的转辙机故障诊断研究 被引量:1
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作者 梁续继 戴胜华 《铁道标准设计》 北大核心 2025年第2期183-190,共8页
铁路信号系统中转辙机的故障率较高,需要采用智能化解决方案对故障进行诊断。传统的解决方案基于电信号,未能充分利用机械电子设备的物理特征。针对这一问题,基于转辙机动作时的声音进行故障诊断。首先,根据转辙机的动作特性提出6种会... 铁路信号系统中转辙机的故障率较高,需要采用智能化解决方案对故障进行诊断。传统的解决方案基于电信号,未能充分利用机械电子设备的物理特征。针对这一问题,基于转辙机动作时的声音进行故障诊断。首先,根据转辙机的动作特性提出6种会影响声音信号的常见机械故障。然后,根据声音诊断在特征提取方面的不同路线,采用3种技术方案。端到端方案通过wav2vec2.0语音识别框架直接进行训练和识别;特征矩阵方案提取声音信号的梅尔倒谱系数(MFCC),通过主成分分析(PCA)得到固定尺寸的特征矩阵,由多分类支持向量机(SVM)进行故障分类;声音图像化方案生成声音信号的语谱图,同时建立卷积神经网络VGG16的轻量化改进模型,将语谱图输入至该模型中进行训练和识别。实验结果表明,3种技术方案均能有效地对包括正常工作和6种故障类型的7种工作状态实现诊断,准确率分别为99.8%、94.2%和96.6%。验证了基于声音进行转辙机故障诊断的3种技术方案的可行性,并体现了语音领域技术在转辙机故障诊断中的应用价值。 展开更多
关键词 转辙机 故障诊断 声音信号 特征提取 wav2vec2.0 MFCC 语谱图
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