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1.
为了提高产品的可靠性,并且在电子设备发生故障时迅速地确定故障源,保障设备的正常运行,基于多信号流模型的诊断建模方法,在多信号流基础上引入了以故障重要先验知识为主的多信号流故障诊断策略,通过引入故障模式的故障概率改进了多信号流诊断技术。该方法已应用于BEPCⅡ磁铁电源接口控制设备故障诊断系统,使用TEAMS测试工具箱建模实现了快速准确的故障诊断和定位,提高了磁铁电源控制设备的故障诊断检测率和隔离率,并且可以方便地扩展到其他设备和系统上。  相似文献   

2.
在利用红外热像仪进行机载电子板卡故障检测中,针对电子板卡结构复杂,解析建模困难的特点,提出了一种基于多信号温度模型的分析诊断方法。通过将机载电子板卡正常工作时的红外温度图像与故障时的进行对比,建立了系统的多信号温度模型,针对多信号温度模型的缺点,提出一种基于贝叶斯网络的测试性建模方法,并给出贝叶斯网络模型的测试性分析方法与指标计算方法,得到模型相关矩阵并进一步进行故障诊断分析,为检测电子元器件故障及老化程度提供了一种有效途径。  相似文献   

3.
随着雷达数字化和智能化,含有多个DSP芯片的高速数字电路模块得到了越来越广泛的应用;针对基于DSP芯片的高速数字电路模块构成的信号处理系统诊断能力弱的问题,提出了通过优化模块BIT软件设计提高模块故障诊断能力的方法;分析了该类模块的BIT测试需求,着重介绍了模块主要BIT测试项目的测试原理和设计方法;通过模块自检软面板对模块BIT测试方法进行了验证;试验结果表明该方法具有实用性强、成本低等优点。  相似文献   

4.
林志文  马锐  万福 《应用声学》2017,25(5):18-20, 25
针对静态故障树诊断序列长、人工可干预度差和不支持多现象并行推理问题,提出了基于D-矩阵和Rollout信息启发搜索算法的故障诊断策略动态生成方法,介绍了基于TEAMS多信号流模型的D-矩阵数据获取方法和Rollout信息启发搜索算法的DLL独立封装技术、输入输出数据规范和动态交互控制方法;基于此开发的交互式智能诊断系统(IIDS)软件平台经实际现场测试诊断验证,对诊断现场出现的多种客观条件,如系统工作模式或测试资源变化、用户干预和多故障现象并发推理等具有很好的适应性,故障覆盖率和隔离率指标高,对提高装备故障诊断的效率、准确性和灵活性具有显著作用。  相似文献   

5.
卞琛  钱育蓉 《应用声学》2014,22(10):3095-30973100
汽车变速箱的故障诊断工作比较复杂,由于传统的诊断方法已不能满足复杂的故障现象, 文中提出了一种基于改进的自适应回归时序模型故障诊断方法;方法采用了基于时间序列故障诊断技术,首先测取工作环境下的振动信号,然后建立被诊断对象的时间序列数学模型,最后用信息距离判别法诊断出故障类型,提高了诊断效率;最后在变速箱进行了实验研究;选用型号为621B40型ICP加速度传感器测取变速箱的振动信号,通过设置模型参数(n,m)来模拟故障检测,实验分析表明,提出的算法可以有效地识别变速箱系统中不同严重程度的故障,且与传统的故障诊断算法相比,提出的算法对提高识别率和降低计算复杂度都有着明显的优势。  相似文献   

6.
为了提高对现代雷达系统的故障诊断能力,开发了一种融合在雷达系统内部的嵌入式测试系统;系统通过在雷达内部布设测试设备,设置故障监测点和加入测试信号,对雷达各部分的工作状态、性能进行监测,用于雷达系统的性能检测和故障诊断,缩短平均维修时间(MTTR); 硬件选用精密的测量仪器和先进的总线通讯技术保证测试精度,软件采用先进的算法,融合了加电BIT、周期BIT和维护BIT等测试手段,保证故障隔离的准确,该系统已在多种雷达系统中得到成功的应用。  相似文献   

7.
矫永康  李小民  毛琼 《应用声学》2014,22(5):1613-1615
在分析虚拟维修训练需求和故障机理的基础上,提出基于多信号模型的电子装备故障建模方法,研究了虚拟环境中故障数据生成与实时检测、故障现象模拟及仿真运行流程等问题;在VC++环境下开发虚拟仪表,并借助实时通信模块获取Virtools环境中虚拟样机上的测试信号;最后,在Virtools中实现了某型无人机飞行指挥与控制系统故障建模与仿真,验证了该方法的可行性;多信号模型可以完整地描述故障的传递轨迹,高效、灵活地构建故障故障机理模型,为受训人员提供了一个实施诊断逻辑的良好训练环境。  相似文献   

8.
为了在多故障情况下对自动驾驶仪故障做出正确诊断,提出了基于相关性矩阵的多故障诊断完备性分析方法,并给出了严格的数学证明;首先对系统的软硬件模块进行分析与划分,利用信息流模型建立故障与测试间的相关性矩阵模型;再根据多故障情况下的诊断完备性分析方法对相关性矩阵进行行列变换,说明在多故障情况下此自动驾驶仪的故障诊断正确率理论上能达到100%,最后构建其故障诊断方法;实际应用表明,此方法对于自动驾驶仪的分析是有效的,可满足系统的指标要求。  相似文献   

9.
军用大型复杂装备组成涉及多个子系统或多个装备,故障诊断涉及上百个分散测试点数据采集和分离模块的诊断推理。传统装备采用集中测试和诊断方法,配套测试系统结构设计复杂、系统故障诊断算法效率低。本文基于D-矩阵故障诊断原理,提出基于多区域Agent的分布式故障诊断结构模型和区域Agent数据协同、区域Agent测试结果仲裁等问题的解决办法,并以某型舰船装备为例,验证了基于多区域代理的分布式故障诊断技术的有效性。  相似文献   

10.
以数字化部件为基础,选取某控制系统为电气系统的代表子系统,开展电气系统BIT技术研究。根据子系统的典型故障,给出了相应的故障检测方法,并设计了故障诊断电路。以样机为基础,采用上电BIT、周期BIT和维护BIT三种方式,对系统的典型故障进行了验证。  相似文献   

11.
鉴于特殊的飞行任务需求,某型号航电综合单一的故障逻辑难以满足多元故障状态下自主重构需求,降低了系统容错性。为解决航电综合多元故障模式难以量化表征影响故障重构的工程难题,创新的提出了一种适用于航电综合的故障检测和重构方法,基于决策表数据挖掘技术的航电综合故障预测流程和多源信息故障检测技术确保常规故障检测率大于98%,航电系统重构状态的量化表征分类方式确保了系统快速重构设计,本文提出的故障检测和重构方法极大地提高航电综合系统的故障检测率与容错能力。  相似文献   

12.
In this paper, a tolerance analog circuit fault diagnosis method based on hierarchical fault dictionary is proposed. During the simulation before test, firstly, the Worse-Case Analysis is used to get the normal characteristics output interval of the circuit under test and the output interval is saved as the first class fault dictionary, which will be used to fault detection; secondly, node-voltage sensitivity sequence is used as fault characteristics to build the second class fault dictionary for locating fault component; thirdly, based on simulation before test according to dividing the component parameters into seven segments, the third class fault dictionary is built to identify the parameter interval of components. In the fault diagnosis stage, based on the established three-class fault dictionary, fault detection, fault locating and component parameter interval identification can be realized respectively according to practical application. The proposed method can improve the efficiency of diagnosis after test and the solution will be a meaningful reference for practical applications. Finally, the simulation experiment demonstrates the effectiveness of the proposed method.  相似文献   

13.
Fault diagnosis of mechanical equipment is mainly based on the contact measurement and analysis of vibration signals. In some special working conditions, the non-contact fault diagnosis method represented by the measurement of acoustic signals can make up for the lack of contact testing. However, its engineering application value is greatly restricted due to the low signal-to-noise ratio (SNR) of the acoustic signal. To solve this deficiency, a novel fault diagnosis method based on the generalized matrix norm sparse filtering (GMNSF) is proposed in this paper. Specially, the generalized matrix norm is introduced into the sparse filtering to seek the optimal sparse feature distribution to overcome the defect of low SNR of acoustic signals. Firstly, the collected acoustic signals are randomly overlapped to form the sample fragment data set. Then, three constraints are imposed on the multi-period data set by the GMNSF model to extract the sparse features in the sample. Finally, softmax is used to as a classifier to categorize different fault types. The diagnostic performance of the proposed method is verified by the bearing and planetary gear datasets. Results show that the GMNSF model has good feature extraction ability performance and anti-noise ability than other traditional methods.  相似文献   

14.
目前在模拟电路故障诊断及测试过程中存在两个问题:测试信号的连续性及容差特性造成的测试信号数量巨大,故障知识表示复杂,测试程序(Test Program,简称TP)的编写多用基于决策知识的人工生成方法。通过对IEEE1232标准的体系结构和诊断推理机要求的分析,论文对IEEEE1232模型体系进行扩充,提出一种包含特征提取技术和多种AI诊断方法的诊断知识库生成协议,设计并实现了符合1232标准知识库的TPS自动生成测试系统。提高了诊断知识的移植性,实现了TPS的自动生成。仿真结果证明了该方案的可行性  相似文献   

15.
提高故障诊断能力对于确保水下机器人系统的稳定运行具有重要意义,故障分类是目前水下机器人故障诊断所面临的一个重要问题。针对水下机器人推进器系统数据特征,提出一种基于信息增益率的加权朴素贝叶斯故障分类算法。首先,计算故障训练样本的先验概率,将各属性的信息增益率作为权值;其次,构建基于增益率加权的朴素贝叶斯分类模型;然后,对检测的故障数据利用分类模型获取具有最大后验概率的故障模式,实现故障分类。与朴素贝叶斯算法和决策树算法相比,仿真实验结果表明基于信息增益率加权的朴素贝叶斯算法的分类成功率更高,能够有效地实现水下机器人的故障分类。  相似文献   

16.
针对模拟电路故障诊断中的容差问题,提出了基于节点导纳矩阵(NAM)的模拟电路故障诊断方法。该方法以NAM为基础,提取被测电路(CUT)的故障特征向量。测试前,用仿真的方法生成被测电路中某一故障对应的故障样本子集,所有类别的故障样本子集构成故障样本集。测试时,测量被测电路的故障特征向量,并根据其与故障样本集中样本的相似性来判断电路发生的故障类型。由于电路的NAM对元件容差不敏感,所以可以很好地克服模拟电路故障诊断中的容差问题。实验结果证明了该方法的有效性。  相似文献   

17.
In order to accurately diagnose the fault type of power transformer, this paper proposes a transformer fault diagnosis method based on the combination of time-shift multiscale bubble entropy (TSMBE) and stochastic configuration network (SCN). Firstly, bubble entropy is introduced to overcome the shortcomings of traditional entropy models that rely too heavily on hyperparameters. Secondly, on the basis of bubble entropy, a tool for measuring signal complexity, TSMBE, is proposed. Then, the TSMBE of the transformer vibration signal is extracted as a fault feature. Finally, the fault feature is inputted into the stochastic configuration network model to achieve an accurate identification of different transformer state signals. The proposed method was applied to real power transformer fault cases, and the research results showed that TSMBE-SCN achieved 99.01%, 99.1%, 99.11%, 99.11%, 99.14% and 99.02% of the diagnostic rates under different folding numbers, respectively, compared with conventional diagnostic models MBE-SCN, TSMSE-SCN, MSE-SCN, TSMDE-SCN and MDE-SCN. This comparison shows that TSMBE-SCN has a strong competitive advantage, which verifies that the proposed method has a good diagnostic effect. This study provides a new method for power transformer fault diagnosis, which has good reference value.  相似文献   

18.
Domain adaptation-based bearing fault diagnosis methods have recently received high attention. However, the extracted features in these methods fail to adequately represent fault information due to the versatility of the work scenario. Moreover, most existing adaptive methods attempt to align the feature space of domains by calculating the sum of marginal distribution distance and conditional distribution distance, without considering variable cross-domain diagnostic scenarios that provide significant cues for fault diagnosis. To address the above problems, we propose a deep convolutional multi-space dynamic distribution adaptation (DCMSDA) model, which consists of two core components: two feature extraction modules and a dynamic distribution adaptation module. Technically, a multi-space structure is proposed in the feature extraction module to fully extract fault features of the marginal distribution and conditional distribution. In addition, the dynamic distribution adaptation module utilizes different metrics to capture distribution discrepancies, as well as an adaptive coefficient to dynamically measure the alignment proportion in complex cross-domain scenarios. This study compares our method with other advanced methods, in detail. The experimental results show that the proposed method has excellent diagnosis performance and generalization performance. Furthermore, the results further demonstrate the effectiveness of each transfer module proposed in our model.  相似文献   

19.
The sparse decomposition based on matching pursuit is an adaptive sparse expression of the signals. An adaptive matching pursuit algorithm that uses an impulse dictionary is introduced in this article for rolling bearing vibration signal processing and fault diagnosis. First, a new dictionary model is established according to the characteristics and mechanism of rolling bearing faults. The new model incorporates the rotational speed of the bearing, the dimensions of the bearing and the bearing fault status, among other parameters. The model can simulate the impulse experienced by the bearing at different bearing fault levels. A simulation experiment suggests that a new impulse dictionary used in a matching pursuit algorithm combined with a genetic algorithm has a more accurate effect on bearing fault diagnosis than using a traditional impulse dictionary. However, those two methods have some weak points, namely, poor stability, rapidity and controllability. Each key parameter in the dictionary model and its influence on the analysis results are systematically studied, and the impulse location is determined as the primary model parameter. The adaptive impulse dictionary is established by changing characteristic parameters progressively. The dictionary built by this method has a lower redundancy and a higher relevance between each dictionary atom and the analyzed vibration signal. The matching pursuit algorithm of an adaptive impulse dictionary is adopted to analyze the simulated signals. The results indicate that the characteristic fault components could be accurately extracted from the noisy simulation fault signals by this algorithm, and the result exhibited a higher efficiency in addition to an improved stability, rapidity and controllability when compared with a matching pursuit approach that was based on a genetic algorithm. We experimentally analyze the early-stage fault signals and composite fault signals of the bearing. The results further demonstrate the effectiveness and superiority of the matching pursuit algorithm that uses the adaptive impulse dictionary. Finally, this algorithm is applied to the analysis of engineering data, and good results are achieved.  相似文献   

20.
兆瓦级NBI加热系统弧流电源故障诊断方法探究   总被引:1,自引:0,他引:1  
针对中国环流器2号A(HL-2A)装置弧流电源的特点,以及弧流电源故障诊断的条件与现状,提出了结合中性束注入(NBI)控制系统的相关功能模块与基于Matlab/Simulink仿真技术构建的故障字典,以实现弧流电源运行状态的在线监测及其故障模式的诊断。NBI控制系统在监测到弧流电源故障状态后,调用存储的弧流电源输出信号进行分析,提取信号的特征值,然后通过查找弧流电源故障字典以诊断出可能的故障模式。结合实验数据论证了该故障诊断法对弧流电源简单故障定位准确,对复杂故障能缩小定位范围,具有原理简单、可操作性强等优点。  相似文献   

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