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针对变电设备故障具有随机性、诊断过程复杂等问题,基于人工蜂群算法、二叉树和支持向量机模型,提出一种基于电力大数据的变电设备故障诊断方法。首先通过人工蜂群算法对支持向量机的参数进行优化,然后针对变电设备故障类型多的特点构造了基于二叉树的多分类支持向量机,最后通过实例验证和分析该方法的有效性和分类性能。结果表明,所提出的故障诊断方法能够准确地实现变电设备故障分类。 相似文献
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支持向量机(Support Vector Machines,SVM)理论在变压器故障诊断中得到了越来越多的应用,由于变压器故障数据有限,在参数的优化选择方面还存在理论支持问题。为及时监测矿用变压器潜伏性故障和提高故障诊断效率,根据支持向量机原理,采用变压器故障时产生的氢气、甲烷、乙烷、乙烯、乙炔的浓度数据,本文提出了支持向量机的参数和参数的交叉验证算法,寻找最佳的参数和参数,利用优化后的参数对训练集进行训练,最终得到最佳的支持向量机模型,并对测试集进行分类,从而诊断出矿用变压器的故障类型。实例研究结果表明,该方法可行,具有较高的故障诊断准确率。 相似文献
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为了提高电子对抗设备对辐射源的识别能力,采用小波包变换法提取信号的时频谱特征,并引入支持向量机完成对辐射源的分类。小波包变换对信号局部的时频特征具有较好的分辨率,支持向量机分类器结构简单、可获得全局优化、泛化能力强。仿真结果表明,基于支持向量机的辐射源分类方法的正确率优于传统算法。 相似文献
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提出一种基于遗传算法和支持向量机的故障诊断模型.该模型采用故障识别中的分类效果作为遗传算法中的适应度函数对故障信号进行特征提取和选择,得到更能反映故障类别的特征,作为识别特征输入多类支持向量机的输入,实现不同类别故障的识别.将该模型应用于变频器功率变换主电路的故障诊断.仿真结果表明,经过遗传算法提取的特征在保持分类精度的基础上,提高了变频器故障识别的效率. 相似文献
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QD128燃气轮机发电机组在超大型IDC/EDC机房的应用 总被引:1,自引:0,他引:1
简要介绍了QD30C和QD128燃气轮机发电机组的构成和主要技术参数,初步探讨了QD30C和QD128燃气轮机发电机组在超大型IDC/EDC机房的配置。提出了QD128燃气轮机发电机组在超大型IDC/EDC机房应用的建议。 相似文献
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Uluyol O. Kyusung Kim Nwadiogbu E.O. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2006,36(4):476-484
In this paper, we present a synergistic approach to startup fault detection and diagnosis (FDD) in gas turbine engines. The method employs statistics, signal processing, and soft computing techniques in a complementary manner to address fault detection at transient conditions. Traditional turbine engine FDD methods are based on engine data collected at steady-state conditions. However, incipient faults are difficult to diagnose using steady-state engine data; only engine faults that are fairly developed can be detected using conventional methods. Because incipient engine component faults are often manifest in the engine startup characteristics, we present a method to characterize the engine transient startup. Engine sensor data during engine startup are recorded in time series format. The sensor profiles corresponding to "good" and "bad" engine startups are sampled using the bootstrap technique. A feature vector is extracted in two steps, and signal processing is followed by the feature vector selection. In the signal processing step, principal component analysis (PCA) is applied to reduce the samples consisting of sensor profiles into a smaller set. In the feature vector selection step, a cost function is defined, and important discriminating features for fault diagnosis are distilled from the PCA output vector. The features obtained from this step are then classified using neural-network-based methods. The "leave-one-out" approach to cross validation is applied to obtain an objective evaluation of the neural network training. The proposed FDD method is evaluated using actual engine startup data, and the results are presented. 相似文献
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风电机组一旦因组件故障而停机,将耗费较长时间排故,给风电场带来较大的经济损失,因此需加强机组运行状态的实时监测,科学评估机组状态,以指导日常检修、维护等工作,有效降低机组发生故障的概率。在明确机组运行状态监测评估需求的基础上,引入大数据技术实现机组运行调度、故障处理等操作,需做好数据收集、分析和推理。把握大数据应用的技术思路,利用存储模块、收集模块、分析系统等加强技术实践应用,有效实现风电机组运行状态的监测评估,为解决风电机组运行管理问题提供有效的技术方案。 相似文献
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新建超大型IDC/EDC机房备用燃气轮机发电机组的选型探讨 总被引:1,自引:0,他引:1
简要介绍QD30C和QD128燃气轮机发电机组的构成和主要技术参数,初步探讨QD30C和QD128燃气轮机发电机组在超大型IDC/EDC机房的配置和选型问题。 相似文献
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为研究送粉参量(送粉量和送粉气流量)变化对激光熔覆过程同轴载气粉末粒子运动行为的影响,建立了数字粒子图像测速试验装置,开发了图像处理软件,得到了不同送粉参量精确的速度场云图以及z轴方向(垂直方向)浓度分布情况。结果表明,在送粉量一定的情况下,随送粉气流量的增加,粉末粒子的初始速度呈线性增大,并使z轴方向速度的增加值加大,而对粉末流浓度影响较小。在气流量一定的情况下,送粉量与粒子速度在一定范围内有一定比例关系,超出送粉量0.33g/s~0.83g/s范围,其影响将减弱。由于粉嘴结构的原因,沿出粉方向存在粉末发散汇聚再发散的变化。汇聚的实现与气体流量关系较大。 相似文献
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Kai Zhu Syed K. Islam Mohammad R. Haider Melika Roknsharifi Jeremy Holleman 《Analog Integrated Circuits and Signal Processing》2012,72(2):383-393
This paper reports a wireless sensor readout circuit for continuous physiological parameters monitoring including a potentiostat, a data generation unit and a frequency-shift-keying (FSK) modulator unit with the low drop-out (LDO) regulator for biomedical implant system. The potentiostat can generate an output potential of 0.7?V for the data generation unit. The data generation unit is designed based on a relaxation oscillator scheme and can be used to sense a current signal from any amperometric biomedical sensor and convert the signal to a square waveform in which the frequency of the square wave signal is proportional to the sensor current. FSK modulation scheme has been selected for wireless transmission. Designed with a very simple ring oscillator, this modulator integrates the modulation functionality into the oscillator itself by using the data signal to control the oscillation frequency. The prototype circuits have been fabricated in a 0.35???m bulk complementary metal-oxide semiconductor (CMOS) process. Working with a regulated 1.8?V supply, the potentiostat consumes only 2???A of current while the data generation unit can generate around 15.7?kHz output frequency with an input current of 1???A. The FSK modulator consumes a total current of around 19???A for a carrier frequency around 1?MHz. An off-chip demodulator is constructed to demodulate the data signal from the FSK modulator and the demodulated signal has less than 1.6?% variation of frequency. 相似文献
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Civardi L. Gatti U. Maloberti F. Torelli G. 《Vehicular Technology, IEEE Transactions on》1994,43(1):40-46
Automotive pollution can be reduced by suitably controlling the mixture that is fed to the cylinders. This can be performed by means of a feedback loop including a lambda sond and a processing unit which controls the electronic fuel injectors. This paper describes a CMOS interface which adapts the output signal of a lambda sensor to allow its feeding into the processing unit. It provides a differential to a single-ended conversion with a good common mode rejection, a level shifting around a given reference voltage, and an accurate voltage gain. Both design considerations and the measurements performed on an integrated test structure are presented. The measured variation of the large-signal voltage gain for an input signal of 0 to 1 V is within ±5% when the input common mode voltage ranges from -1 V to 1 V with respect to the negative supply voltage. An output voltage with a precision within ±1 mV is obtained in the presence of an input voltage corresponding to the stochiometric composition of the mixture 相似文献
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为给舰用发动机提供先进和可靠的动力装置控制系统,针对国内某型舰用燃气轮机实施了控制系统的数字化改造.新研制的数字控制系统由电子控制器、适合数字式控制的燃油供油装置、燃油计量装置和原有燃油泵组成.该系统通过了半物理仿真试验,试验结果证明,与原机械液压控制系统相比,该系统具有控制精度高、便于调节控制规律、安全可靠等优点. 相似文献