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Very Short-Term Wind Direction Multistep Forecast Based on VMD-LSTM [PDF]
, 2023 [Introduction] In order to accurately forecast the wind direction in the next 4 hours, a very short-term wind direction multistep forecast algorithm based on VMD-LSTM（Variational Mode Decomposition-Long Short-Term Memory） is proposed.
Desheng MIAO +5 more
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Modal Parameter Identification of Low Frequency Oscillation in Power System Based on Ambient Data [PDF]
, 2022 Low frequency oscillation is one of the key problem affecting the safe and stable operation of interconnected power system, variational modal decomposition (VMD) was used to extract low-frequency oscillation signals from ambient data, and a method of low-
GAO Yanfeng, HWANG Jin Kwon, YAN Hongyan
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Multi frequency hopping network station sorting based on joint feature clustering in complex environment [PDF]
, 2023 In order to remove interference from hybrid signals and sort each frequency hopping station signal, a multi frequency hopping network station sorting algorithm based on joint feature clustering was proposed.Firstly, short-time Fourier transform was ...
Jiazheng WANG +4 more
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Gaoya dianqi, 2021 为了及时有效地诊断变压器绕组松动故障,针对变压器空载合闸振动信号,提出了一种基于变分模态分解(VMD)的分析方法。首先运用VMD对绕组松动前后变压器表面合闸振动信号进行最优模态分解,建立信息熵—峭度—相关系数综合评价模型,并运用熵权—TOPSIS法提取特征模态分量;通过计算变压器振动信号能量熵进一步判定绕组状态;最后搭建测试平台进行实验验证。结果表明,绕组松动和正常状态下变压器振动信号在特征频率和能量分布上均存在明显差异,该方法为变压器绕组松动故障诊断提供了新的思路。
张九思 +4 more
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Gaoya dianqi, 2022 高压断路器合分闸线圈电流中含有大量信息，监测和分析线圈电流信号对于高压断路器故障检测和诊断意义重大。文中提出基于变分模态分解的方法提取线圈电流特征值，采用变分模态法分解断路器合分闸线圈电流信号，并对所得到的经验模态分量求其中心频率，根据频谱中峰值所对应的时间点，提取线圈电流信号的特征值。实验结果表明：使用该方法能够准确且有效地提取合分闸线圈电流信号的特征值。
庄瑞锋, 陈丽安, 肖梁贤
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Gaoya dianqi, 2023 随着电力系统中变压器容量的不断增加，变压器绕组松动缺陷引起的影响也愈发严重，故需进行故障诊断。针对利用振动信号进行变压器绕组松动缺陷诊断问题，提出基于变分模态分解（VMD）排列熵（PE）的变压器振动信号特征提取方法与天牛须搜索（BAS）优化支持向量机（SVM）的变压器绕组松动缺陷诊断方法。首先对一台实际110 kV变压器设置不同松动状态，采集绕组正常与不同松动程度状态下振动信号；其次，采用变分模态分解结合排列熵进行变压器绕组松动缺陷特征提取；再次，采用天牛须搜索优化支持向量机算法进行绕组松动状态模式识别。
顾仲翔 +4 more
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Dizhen xuebao, 2022 针对低信噪比条件下微震初至拾取准确度低的问题，基于信号幅度变化引入权重因子，对传统长短时窗比值（STA/LTA）算法进行改进，提高初次拾取精度。为了进一步降低拾取误差，对变分模态分解（VMD）算法进行优化，基于互相关系数和排列熵准则自适应确定VMD分解层数，对初次拾取结果前后2—3 s的记录进行优化VMD，并计算分解后各本征模函数（IMF）的峰度赤池信息准则值，得到各IMF的到时，以各IMF的拾取结果及能量比综合加权得到二次拾取到时。仿真实验表明：改进后的STA ...
Juan Meng, Yanxiong Wu, Yanan Li
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基于CEEMDAN-SG-BiLSTM的变压器油中溶解气体体积分数预测
Gaoya dianqi, 2023 变压器油中溶解气体体积分数可对变压器潜伏故障诊断提供重要依据，为了更精确的预测变压器油中溶解气体体积分数，提出了CEEMDAN结合BiLSTM网络的组合预测方法，先针对EMD中的模态混叠现象和EEMD重构误差较大的问题，提出了CEEMDAN，将气体序列分解，得到模态分量，并对高频波动分量进行Savitzky-Golay(SG)滤波，消弱高频分量中的极值点和噪声干扰。然后利用BiLSTM网络对各个分量进行预测，进一步提高特征提取的完整性。叠加重构所有分量的预测结果，得到变压器油中溶解气体体积分数预测值 ...
陈铁 +5 more
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Research on language recognition algorithm based on improved CFCC feature extraction [PDF]
, 2022 Aiming at the problem of low language recognition rate under low signal-to-noise ratio, a language recognition method based on fractional wavelet transform was proposed.Firstly, the adaptive filtering algorithm was used to filter the noise of the noisy ...
Hua LONG +4 more
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Mine cable partial discharge denoising method based on multivariate variational mode decomposition and improved wavelet threshold [PDF]
The insulation state of the mine cable plays an important role in the stable operation of the mine power supply system. Partial discharge on-line monitoring is an important means of cable insulation state monitoring.
Jiyuan CAO +6 more
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