共查询到20条相似文献,搜索用时 31 毫秒
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XIEChun-li XIAHong LIUYong-kuo 《船舶与海洋工程学报》2005,4(1):30-33
The work condition of nuclear power plant (NPP) is very bad, which makes it has faults easily. In order to diagnose the faults real time, the fusion diagnosis system is built. The data fusion fault diagnosis system adopts data fusion method and divides the fault diagnosis into three levels, which are data fusion level, feature level and decision level. The feature level uses three parallel neural networks whose structures are the same. The purpose of using neural networks is mainly to get basic probability assignment (BPA) of D-S evidence theory, and the neural networks in feature level are used for local diagnosis, D-S evidence theory is adopted to integrate the local diagnosis results in decision level. The reactor coolant system is the study object and we choose 2# steam generator Utubes break of the reactor coolant system as a diagnostic example, The experiments prove that the fusion diagnosis system can satisfy the fault diagnosis requirement of complicated system, and verify that the fusion fault diagnosis system can realize the fault diagnosis of NPP on line timely. 相似文献
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船舶柴油发电机转速神经网络容错控制 总被引:2,自引:0,他引:2
结合人工神经网络与智能容错控制,形成船舶柴油发电机转速神经网络容错控制。对由故障诊断后获取的特征值进行归一化处理,把经过处理的特征值作为神经网络的输入样本集,设计输出样本集,建立BP神经网络和ELMAN神经网络,用整理后的数据训练神经网络,使神经网络具有容错控制功能,并对神经网络模型进行仿真测试。仿真试验显示可以实现对船舶电力系统容错控制,保证船舶的安全运行。 相似文献
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A marine propulsion system is a very complicated system composed of many mechanical components.As a result,the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft.It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis.For this reason,a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems.To monitor the gear conditions,the bispectrum analysis was first employed to detect gear faults.The amplitude-frequency plots containing gear characteristic signals were then attained based on the bispectrum technique,which could be regarded as an index actualizing forepart gear faults diagnosis.Both the back propagation neural network (BPNN) and the radial-basis function neural network (RBFNN) were applied to identify the states of the gearbox.The numeric and experimental test results show the bispectral patterns of varying gear fault severities are different so that distinct fault features of the vibrant signal of a marine gearbox can be extracted effectively using the bispectrum,and the ANN classification method has achieved high detection accuracy.Hence,the proposed diagnostic techniques have the capability of diagnosing marine gear faults in the earlier phases,and thus have application importance. 相似文献
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船舶动力装置工作过程中会产生大量多域故障信号,通过收集、挖掘隐藏的关联信号,可以解决船舶动力装置在故障诊断中面临的诊断时长问题.文章采用K-均值聚类算法(K-means)对数据进行聚类,聚类结果输入BP神经网络进行模型训练,并在此基础上,设计了主成分分析法(PCA)对模型进行优化.结果 显示,2种算法都能有效降低网络诊... 相似文献
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基于神经网络的柴油机遥控系统故障智能诊断研究 总被引:1,自引:0,他引:1
为了克服传统模拟电路故障诊断方法的不足,通过对船舶柴油机遥控系统工作原理的分析,提出采用BP神经网络诊断船舶主机遥控系统的智能诊断方法。介绍BP神经网络结构确定方法及其数值优化技术,并以具体电路模块为例探讨神经网络在船舶柴油机遥控系统故障诊断中的应用。通过Matlab仿真可以发现基于BP神经网络的电路故障诊断方法具有自适应性好、训练时间短、准确性高等特点。 相似文献
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通过分析测控装备故障诊断专家系统的目的和任务,将模糊神经网络理论与专家系统相结合用于测控装备故障诊断,建立了故障诊断专家系统的模型。探讨了故障诊断专家系统中知识库的构建及维护、不精确推理等问题。用面向对象分析方法分析故障诊断专家系统,并用软件加以实现。 相似文献
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基于虚拟仪器技术,利用LabVIEW7.1编写采集分析程序,并以Matlab Script节点形式调用在Matlab里训练成功后的BP神经网络程序,开发了柴油机供油系故障诊断系统。该系统由PCI-6221采集卡获取测取燃油压力波形,利用小波包分解提取特征信号,并组成特征向量输入训练成功的BP神经网络进行典型故障识别,诊断结果通过人机界面输出,从而实现了故障诊断的智能化。 相似文献
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基于模糊神经网络的燃气轮机故障诊断专家系统研究 总被引:1,自引:0,他引:1
针对神经网络和传统专家系统在燃气轮机故障诊断过程中各自存在的局限性,提出了一种将模糊神经网络和专家系统相结合的方法.解决了以往专家系统专家知识获取困难和不能描述模糊性知识的缺陷.通过已开发的某型三轴燃气轮机运行模拟器取得典型的故障样本完成了对模糊神经网络的训练工作,最后选取一定数量的测试样本对网络进行了测试,证明了系统的可行性.结果表明,该方法行之有效,在燃气轮机故障诊断领域中有很好的应用价值. 相似文献
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