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K-S变换及其电网超谐波时频分析应用

湖南大学学报（自然科学版） 2024年第6期51卷 128-136页

作者：滕召胜梁成斌唐求张雷鹏成达湖南大学电气与信息工程学院湖南长沙410082

依据FFT→优化窗→IFFT思路,突破线性时频变换的窗函数积分性能桎梏,实现高性能优化窗函数的线性时频变换应用,建立新型时频变换算法——K-S变换.对信号x(t)的FFT频谱向量进行频移处理后,与该频移点下Kaiser优化窗的频谱向量进行Hadamar... 详细信息

依据FFT→优化窗→IFFT思路,突破线性时频变换的窗函数积分性能桎梏,实现高性能优化窗函数的线性时频变换应用,建立新型时频变换算法——K-S变换.对信号x(t)的FFT频谱向量进行频移处理后,与该频移点下Kaiser优化窗的频谱向量进行Hadamard乘积,再将乘积结果进行FFT逆变换(IFFT),构造出K-S变换复时频矩阵,由此获得x(t)的时间-频率-幅值、时间-频率-相位三维信息;给出逆变换的数学推导与局部性质、线性性质和变分辨率特性;0~150 kHz电网的稳态与时变超谐波信号仿真实验表明,K-S变换的时域、频域分辨能力均优于流行的短时傅里叶变换、S变换,具有优良的变分辨率性能;0~40 kHz超谐波信号的实测证明,基于K-S变换的超谐波电压幅值测量绝对误差均小于0.032 3 V.

关键词： K-S变换时频分析 Kaiser优化窗变分辨率特性电网超谐波

Improved method for prediction of milled rice moisture content based on Weibull distribution

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 159-165页

作者： Jing Ling zhaosheng teng Haijun Lin School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China College of Polytechnic Hunan Normal UniversityChangsha 410081China

The loss on drying method,which is regarded as the standard method of rice moisture content analysis,provides the most reliable results but is both labor intensive and time *** order to improve the detection efficiency of the loss on drying method,this study investigated the drying characteristics of milled rice and developed an information fusion algorithm with which to predict milled rice moisture content based on the Weibull distribution and Levenberg-Marquardt(LM)*** of the Weibull distribution model was investigated regarding its description of the drying kinetics of milled rice during infrared *** adaptive mechanism was applied to algorithm design,with the starting point of the estimation algorithm determined by calculating the drying rate at each measuring point,and the end-point distinguished using a two-level threshold *** calculated results were then compared with the measured data regarding the infrared drying of milled *** milled rice samples varying in moisture content from 14.44%-17.67%(dry basis),the relative error between predicted and observed values ranged 0.0037-0.0589,with a reduction in test time of 50.71%-67.87%.

关键词： milled rice moisture content Weibull distribution Levenberg-Marquardt(LM)algorithm information fusion loss on drying method

Infrared drying kinetics and moisture diffusivity modeling of pork

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 302-311页

作者： Ling Jing teng zhaosheng Lin Haijun Wen He College of Electrical and Information Engineering Hunan UniversityChangsha 410082China School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021China College of Polytechnic Hunan Normal UniversityChangsha 410081China

This study investigated the drying kinetics of pork slice in infrared drying *** temperature,slice thickness and initial moisture content were selected as influencing factors on the drying characteristics and drying rate of pork *** curves obtained from the experimental data were fitted to semi theoretical and/or empirical thin layer drying *** effects of drying temperature and slice thickness on the model constants were evaluated by the multiple regression *** the models were compared according to three statistical indexes,i.e.,root mean square error,chi-square and modeling *** slice thickness,drying temperature and initial moisture content have significant influences on the effective diffusivity coefficient of *** results showed that the drying rate of pork slices increased with the increases of drying temperature and initial moisture *** decreases of slice thickness also led to an increase of drying *** Henderson and Pabis model can best describe the drying curves of pork.

关键词： infrared drying pork slice drying kinetics effective moisture diffusivity multiple regression analysis

Hanning self-convolution window and its application to harmonic analysis

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Science China(Technological Sciences) 2009年第2期52卷 467-476页

作者： WEN He teng zhaosheng GUO SiYu WANG JingXun YANG BuMing WANG Yi CHEN Tao College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

The Hanning self-convolution window (HSCW) is proposed in this paper. And the phase difference correction algorithm based on the discrete spectrum and the HSCW is given. The HSCW has a low peak side lobe level, a high side lobe roll-off rate, and a simple spectrum representation. Hence, leakage errors and harmonic interferences can be considerably reduced by weighting samples with the HSCW, the parameter estimation by the HSCW-based phase difference correction algorithm is free of solving high order equations, and the overall method can be easily implemented in embedded systems. Simulation and application results show that the HSCW-based phase difference correction algorithm can suppress the impacts of fundamental frequency fluctuation and white noise on harmonic parameter estimation, and the HSCW is advantageous over existing combined cosine windows in terms of harmonic analysis performance.

关键词： hanning self-convolution window FFT phase difference spectral leakage frequency fluctuation

基于多CPU与相位差校正的高精度谐波功率测量

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电力系统自动化 2009年第11期33卷 89-93页

作者：曾博滕召胜湖南大学电气与信息工程学院湖南省长沙市410082

快速傅里叶变换(FFT)应用于谐波分析与测量时容易因频谱泄漏影响测量准确度。研究Rife-Vincent窗的旁瓣特性,提出了一种基于Rife-Vincent窗频谱相位差校正的谐波分析与谐波功率测量方法。在此基础上设计了一种新型三相谐波电能表,给出... 详细信息

快速傅里叶变换(FFT)应用于谐波分析与测量时容易因频谱泄漏影响测量准确度。研究Rife-Vincent窗的旁瓣特性,提出了一种基于Rife-Vincent窗频谱相位差校正的谐波分析与谐波功率测量方法。在此基础上设计了一种新型三相谐波电能表,给出了基于TDK6513H+ADSP-BF533+M30624FGPFP的多CPU电力谐波精确测量解决方案。实验结果表明,应用所提出的谐波分析算法时,仪器的性能优于GB/T 17833—1999及GB/T 14549—1993的要求,基波有功功率测量误差小于0.2%,谐波电压测量相对误差小于1%,谐波电流测量相对误差小于3%,谐波相位测量误差绝对值小于2°,适合于高精度谐波功率测量。

关键词：谐波功率谐波分析 Rife-Vincent窗相位差校正

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基于CAN总线的储粮水分自动测试系统

电工技术学报 2000年第4期15卷 76-79,75页

作者：滕召胜湖南大学电气与信息工程学院 410082

粮食的安全储藏是关系到国计民生的重大战略问题。本文提出了一种基于CAN总线的储粮水分自动测试系统 ,介绍了系统的工作原理、硬件结构和软件流程。实际应用表明 ,这种自动测试系统能够实时检测仓储粮食的水分含量 ,准确提供储粮状态信... 详细信息

粮食的安全储藏是关系到国计民生的重大战略问题。本文提出了一种基于CAN总线的储粮水分自动测试系统 ,介绍了系统的工作原理、硬件结构和软件流程。实际应用表明 ,这种自动测试系统能够实时检测仓储粮食的水分含量 ,准确提供储粮状态信息 ,提高储粮的安全性 ,因而具有广泛的应用前景。

关键词： CAN总线储粮水分自动测试系统

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谱质心在电力谐波分析中的应用

中国电机工程学报 2013年第31期33卷 73-80,9页

作者：曾金芳滕召胜湖南大学电气与信息工程学院湖南省长沙市410082

该文给出了连续频谱和离散频谱的谱质心计算公式,讨论了谱质心应用于频谱校正的原理和步骤。通过计算离散频谱正频率段的谱质心估计信号频率,根据邻近谱质心的峰值谱线估计信号幅值和相位。对于谐波信号,引入子带谱质心概念,根据谐波次... 详细信息

该文给出了连续频谱和离散频谱的谱质心计算公式,讨论了谱质心应用于频谱校正的原理和步骤。通过计算离散频谱正频率段的谱质心估计信号频率,根据邻近谱质心的峰值谱线估计信号幅值和相位。对于谐波信号,引入子带谱质心概念,根据谐波次数将谐波分成多个子带,计算每个子带的谱质心估计各次谐波参数。仿真实例表明,谱质心法能提高谐波分析的准确度,有效克服基波频率波动和噪声对谐波分析的影响。与传统的比值法、相位差法和能量重心法相比,谱质心法可以避免繁琐的峰值搜索和复杂的谱线插值计算,不需要推导窗函数的能量特性,是一种简单实用的电力谐波分析方法。

关键词：谱质心子带谱质心频谱分析参数估计电力谐波分析余弦相似度