Research on Methods of Modeling and Fault Diagnosis for Micro Direct-Current Motors [PDF]
, 2015 直流微电机以体积小、重量轻、便于控制等优点被广泛应用于生产消费领域，在微型精密仪器中尤为重要。为了保证产品出厂品质，生产过程必须对直流微电机进行100%检测。目前检测主要依靠人工的经验来判断电机的好坏，其工作量大，生产效率低，漏检现象严重，导致电机出厂质量不稳定。因此有必要寻找一种简便和可靠的直流微电机在生产线上的故障检测技术。该技术即可以对出厂前的直流微电机进行自动在线检测，以保证直流微电机的出厂合格率；又可以推广应用于其他永磁直流电机的故障检测与诊断。 通过分析空载下直流电机的动态数学模型 ...
谢志平
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Research of Sensor Faults Detection Based on Particle-Filtering methods [PDF]
, 2016 传感器故障诊断一直以来都是工业界与学术界研究的热点话题。由于传感器通常安装在现场，一般在工作一段时间以后，其性能会受到现场恶劣环境的影响，甚至发生故障。据统计，在控制系统的各种故障中，传感器和执行器的故障占80%左右，所以在控制系统的诊断中，首先应进行传感器的故障诊断，对其状态进行有效的监视和评估。 本文研究的内容主要为：针对非线性系统中的传感器故障问题，提出了一种基于粒子滤波与假设检验方法的故障诊断算法，对几种常见类型的传感器故障进行在线、实时诊断 ...
戴思弘
core
Research on Fault Diagnosis Method of Photovoltaic Arrays Based on Improved Grey Wolf Algorithm Optimized Extreme Learning Machine [PDF]
ObjectivesPhotovoltaic arrays operating under complex outdoor conditions encounter various fault types with varying degrees of severity. To accurately assess the working status of photovoltaic arrays, a fault diagnosis method based on an improved grey ...
HAN Maolin +4 more
core +1 more source
Analysis of Current Situation and Future Development of Offshore Wind Power Industry [PDF]
, 2023 [Introduction] Under the trend of accelerating the clean transformation of coastal energy and adjusting the industrial structure, offshore wind power will become an important support for the safe, clean and efficient transformation of power energy in ...
Jiachang LIU +3 more
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断路器合闸输电线路单相接地短路故障线路两侧短路电流计算与分析
Gaoya dianqi, 2019 输电线路发生单相接地故障,当短路故障不能及时消除时,线路两侧的断路器在重合闸操作过程中可能存在合闸短路故障的工况。运行经验表明,线路两侧断路器在合闸短路故障时,流过断路器的短路电流存在延迟过零的现象,从而导致断路器开断失败。文中通过建立单相等值电路模型,理论分析了在不同的合闸短路工况下故障线路两侧断路器流过的短路电流表达式,结论表明,由于后合闸断路器对电路拓扑的改变,使得先合闸断路器中流过的短路电流可能会出现延迟过零。又进一步分析与讨论了合闸初始相角α、间隔时间Δt、幅值比K对短路电流的影响规律。最后 ...
张瑞, 王克杰
doaj
Fault Characteristic Study Based on FLUX 2D for Large Synchronous Generators With Stator Winding Inter-turn Short Circuits Under Rated Operating Conditions [PDF]
, 2013 该文采用单一绕组分析和有限元分析相结合的方法,研究大型同步发电机在额定运行方式下定子绕组匝间短路故障特性。该方法同样适用于确定故障条件下的电流和转矩。对于内部故障情况的电磁瞬态仿真必须考虑到一些特殊措施,如单一绕组和电网之间正确的连接对于模拟内部故障是相当关键的。以往的结果表明,在内部磁场非对称的情况下,基于等效电路的经典算法是不适用的。该文通过对汽轮发电机匝间短路故障进行系统的研究,表明:其短路电流、相电流、转矩和径向力与短路的位置及匝数紧密相关。在一些短路情况下,发电机将产生很大的局部电流 ...
J.Rosendahl +3 more
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Gaoya dianqi, 2013 阀故障电流试验作为考核换流阀短路电流耐受能力的运行型式试验项目,必须在与实际运行工况最为等价的试验回路上进行。短路发电机系统既能提供阀故障电流试验要求的短路电流,同时又能够在短路电流过零时刻立即提供预期恢复电压,具有较高的等价性,是进行阀故障电流试验的一种理想回路。短路发电机系统进行阀故障电流试验时,先利用阀运行试验合成回路提供换流阀正常工况下的运行条件,在换流阀结温及运行参数满足要求时,通过短路发电机系统模拟实际运行中的突发短路故障,使换流阀流过标准规定的短路故障电流,并承受恢复电压 ...
胡治龙 +4 more
doaj
Analysis Based on the Simplified Sequence Component Method [PDF]
, 2013 分析了对称分量存在不足,结合平衡线路的模变换数学特性,得出简化序分量法在输电线路的故障分析原理。提出了简化序分量法在短路和断线故障分析及选相原理,解决了距离保护作为yd变压器远后备保护存在的问题。On the basis of an analysis of the disadvantages of symmetrical component,under consideration of mathematical characteristics of the modular transformation ...
谢珍贵, 黄兴平
core
Research on Doubly-Fed Wind Turbine Shaft System With Virtual Inertia for Torsional Vibration Analysis [PDF]
ObjectivesShafting mathematical model of wind turbine is the basis of torsional vibration characteristics analysis. Shafting model is very important for the reliability of analysis results.
SAN Jiqiang, SUN Zhenglong
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Fault diagnosis of ship diesel power distribution system based on WOA-RF algorithm [PDF]
ObjectiveThe marine diesel generator (DG) power distribution system is crucial for ship navigation. However, due to the harsh marine environment, frequent failures occur. Therefore, a fault diagnosis method based on whale optimization algorithm-optimized
Daojie RUAN +5 more
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