共查询到20条相似文献,搜索用时 15 毫秒
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A method of calculating transients in three-phase modelled power grids is presented. First, important devices are modelled by transient device admittance matrices. According to the configuration of the grid, these matrices are put together to form a transient node admittance matrix. Based on this result, transient gate impedance, admittance and hybrid matrices are derived. Their main properties are discussed. 相似文献
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研究了一般离散时间代数Riccati方程(GDTARE)的解矩阵的估计问题。利用矩阵特征值的性质等推导出GDTARE的解矩阵的上下界,并建立了求解上下界的迭代格式,使用迭代格式可对上下界进行改进。最后,通过比较分析和算例验证说明了本文所得结果较已有研究结果更具有一般性和较小的保守性。 相似文献
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研究区间多项式矩阵族的.鲁棒D稳定性问题,给出检验区间多项式矩阵族的鲁棒D稳定的充分条件。该多项式矩阵仿射地依赖于独立摄动的不确定参数,考虑D域为广义二阶线性矩阵不等式(LMI)域,采用LMI方法,证明了该问题等价于LMI可解性问题,同时采用多方向线性搜索和LMI可解性问题相结合,给出了求解区间多项式矩阵族的稳定半径和各摄动方向的最大稳定域的算法,并通过一个实例说明该方法的有效性。 相似文献
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Federico Bizzarri Angelo Brambilla Giancarlo Storti Gajani 《International Journal of Circuit Theory and Applications》2013,41(7):743-752
Conventional shooting methods cannot be used to determine the steady‐state solution of circuits whose model is characterised by a vector field exhibiting zero order discontinuities. In the analysis of circuits working on a stable limit cycle, this limitation prevents the use of methods that exploit Floquet theory to compute the variational model and thus the properties of the fundamental matrix and, for example, phase noise in oscillators. In this paper, we use an improved shooting method that solves this drawback by resorting to saltation matrices and show how this method makes possible the correct computation of the first left eigenfunction (known as ppv ) of the fundamental matrix. ppv s are a key aspect in determining phase noise. The results obtained through numerical simulations are compared with measurements on a relaxation oscillator serving as a simple but significant comparison vehicle. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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分析了具有等价行向量组的两矩阵之间行向量组、列向量组及矩阵所对应的齐线性方程组的解之间关系,通过对行最简式定义的分析,得出两个结论:1.行最简式相同是矩阵行向量组等价的充要条件,2.矩阵行最简式是唯一的。使得对向量组等价性的研究转化为只需对矩阵作行初等变换即可实现,得到了研究向量组等价性的一种简洁、有效的方法,同时使得行最简式在矩阵研究中变得更为重要。 相似文献
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基于关联矩阵的电网拓扑辨识 总被引:42,自引:9,他引:33
提出了基于关联矩阵的电网拓扑辨识算法。该算法使用节点-支路关联矩阵表示电网路的基本拓扑结构,定义了矩阵的“与-或”乘法运算,利用连通性的传递性质,实现对电网络的拓扑辨识。在此基础上,利用节点-支路关联矩阵和节点-节点连通矩阵的对称性,提出了加快计算的技术和实现方法,该算法即可以通过汇编语言或高级语言编程实现,也可以由单片机系统或ASIC等硬件方法实现。 相似文献
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Mahmoud Atashbar Mohammad Hossein Kahaei 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(1):97-99
The l1‐SVD is an efficient method for spatial sparsity based direction of arrival (DOA) estimation of narrowband signals. We propose a coherent strategy for extension of the l1‐SVD method to wideband signals. In this method, focusing matrices are used for transferring different frequency bins data to the reference bin, and then the transformed data are combined. Finally the l1‐SVD is applied for the combined data. The proposed method outperforms the non‐coherent strategy with a lower computational burden. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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在直流系统可靠性评估中,传统FD法需要建立状态空间图,求解过程繁琐。提出一种基于参数矩阵化的FD法,即将所有子系统的相关参数矩阵化,包含容量矩阵、容量概率矩阵、状态转移率矩阵。通过矩阵运算实现子系统组合,从而避免建立状态空间图,在保证计算精度的同时,使子系统组合计算简明快速,克服了传统方法在元件众多结构复杂时计算困难的弊端。对一个双极两端柔性直流输电系统进行了可靠性建模与评估,并研究了元件故障率变化对柔性直流输电系统可靠性的影响。 相似文献
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基于非对称模型的发电机转子-轴承系统动力特性分析 总被引:7,自引:5,他引:2
该文在旋转坐标下建立了发电机非对称转子 -轴承系统的数学模型 ,推导了非对称转子、轮盘和轴承的传递矩阵。针对传统传递矩阵法存在的对多自由度非对称转子 -轴承系统的数值不稳定问题 ,该文在构造系统非对称部件的传递矩阵时 ,引入了Riccati变换 ,使之适合于复杂实际非对称转子动力特性的求解。将这种方法应用于某 6 5 0MW核电发电机转子 轴承系统的动力特性计算 ,计算结果与实验结果吻合的较好 ,证明该方法能解决传统方法不能解决的实际非对称转子 轴承系统动力特性 (临界转速、不平衡响应和稳定性等 )的计算问题 ,为非对称电机转子的设计提供了更准确的计算方法。 相似文献
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一种非接地配电系统潮流计算的改进方法 总被引:2,自引:0,他引:2
针对配电网潮流计算中采用相电压分量作为计算变量引起的变压器导纳矩阵出现奇异等问题,提出了一种非接地配电系统潮流计算的改进方法.该方法采用线电压分量作为计算变量,基于此建立了相应的传输线、变压器、感应电动机等元件模型,并将这些模型应用于回推-前推潮流算法中.该方法解决了非接地配电网潮流计算中变压器导纳矩阵出现奇异的问题,克服了非接地系统中参考点的任意选取导致潮流计算结果出现不唯一的情况,更加符合实际物理情形,同时减小了计算量.理论分析和实例计算表明,该方法是一种有效的非接地配电系统潮流计算方法. 相似文献
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在一些对采样数据速率有严格要求的实际应用中,对低采样率的压缩感知具有广泛需求。基于LDPC矩阵的特点,提出了一种类似托普利兹矩阵的压缩感知测量矩阵,所提出的测量矩阵构成方法易于实现。仿真结果表明,在低采样率的情况下,采用本文所提方法构造的测量矩阵不仅有着与常用稀疏测量矩阵相比更好的稀疏性,且将其用于图像压缩感知时可获得较好的图像重构质量。 相似文献
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G.N. KorresAuthor Vitae 《Electric Power Systems Research》2011,81(7):1388-1402
This paper presents an efficient numerical method for observability analysis of systems including both conventional (SCADA) measurements and synchronized phasor (PMU) measurements, using integer preserving Gaussian elimination of integer coefficient matrices. The observable islands are identified in a noniterative manner, by performing backward substitutions on the integer triangular factors of the integer gain matrix. Multiple placement of conventional and phasor measurements for a system that is found to be unobservable is done by a direct method, using the integer triangular factors of a Gram matrix associated with a reduced size Jacobian matrix. Since all computations performed are exact, no round-off error, numerical instability, or zero identification problems occur. The IEEE 14-bus system is used to illustrate the steps of the proposed method. Test results for the IEEE 300-bus and the FRCC 3949-bus systems are provided to demonstrate the features of the proposed algorithms. 相似文献
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本文提出了一种在多机电力系统中选择灵活交流,输电稳定器(FACTS-basedstabilizer)安装地点和反馈信号的新方法-降价模态分析法,这一方法形成于一组降价模态分析公式,它由电力系统推广Philips-Heffron模型得到,与由全系统状态矩阵进行的通常模态分析完全等效,降价模态分析法能够保证,所有参加分析 矩阵的维数均不超过系统中的发电机数,这样,不仅大大降低了分析所需的运算量和计算机 相似文献
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Vincent Mussot Guillaume Mercère Thibault Dairay Vincent Arvis Jérémy Vayssettes 《International Journal of Adaptive Control and Signal Processing》2021,35(4):591-611
A problem frequently encountered in Kalman filtering is the tuning of the noise covariance matrices. Indeed, misspecifying their values can drastically reduce the performance of the Kalman filter. Unfortunately, in most practical cases, noise statistics are not known a priori. This paper focuses on a method relying on subspace model identification theory to determine them accurately. This solution is developed for linear time invariant systems with stationary random disturbances having constant covariance matrices. Practically, these noise covariance matrices are determined from the comparison between an estimated state space representation and the discrete time state space representation involved in the Kalman filter equations. The method developed in this paper departs from most of the solutions available in the literature by the fact that it does not need any tuning parameter to be chosen by the user. After discussing theoretical results, several numerical examples are given to demonstrate the efficiency of the approach. 相似文献