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Extra Time Dimension: Deriving Relativistic Space-Time Transformations, Kinematics, and Example of Dimensional Compactification Using Time-Dependent Non-Relativistic Quantum Mechanics
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作者 Sajjad Zahir 《Journal of Modern Physics》 2023年第10期1333-1354,共22页
We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are d... We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are derived, leading to a new expression for the speed limit. Extending the ideas of Einstein’s Theory of Special Relativity, concepts of five-velocity and five-momenta are introduced. We get a new formula for the rest energy of a massive object. Based on a non-relativistic limit, a two-time dependent Schrödinger-like equation for infinite square-well potential is developed and solved. The extra time dimension is compactified on a closed loop topology with a period matching the Planck time. It generates interference of additional quantum states with an ultra-small period of oscillation. Some cosmological implications of the concept of four-dimensional versus five-dimensional masses are briefly discussed, too. 展开更多
关键词 Two-Time Physics Special Theory of Relativity Kaluza-Klein Theory Time-Dependent Schrödinger Equation compactification
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Effects of Compactification on Free Massive Scalar Fields in Five-Dimensional Space-Time with an Extra Time Dimension: Analysing Some Results
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作者 Sajjad Zahir 《Journal of Modern Physics》 2023年第12期1600-1616,共17页
This paper deals with some aspects of two-time physics (i.e., 2T + 3S five-dimensional space) for a Minkowski-like space with distinct speeds of causality for the time dimensions. Detailed calculations are provided to... This paper deals with some aspects of two-time physics (i.e., 2T + 3S five-dimensional space) for a Minkowski-like space with distinct speeds of causality for the time dimensions. Detailed calculations are provided to obtain results of Kaluza-Klein type compactification for free massive scalar fields and abelian free gauge fields. As already indicated in the literature, a tower of massive fields results from the compactification with mass terms having signs opposite to those of the ones appearing in other five-dimensional theories with an extra space dimension. We perform elaborate numerical calculations to highlight the magnitude of the imaginary masses and ask if we need to explore alternative compactification techniques. 展开更多
关键词 Two-Time Physics Theory of Special Relativity Kaluza-Klein Theory compactification Klein-Gordon Equation TACHYONS Abelian Gauge Theory
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On the Inverse Limit of Higson Compactifications 被引量:1
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作者 曹阳 孙以丰 《Northeastern Mathematical Journal》 CSCD 2002年第2期95-98,共4页
Higson have introduced the conception of "Higson’s corona" (see [1]). For a given metric space X, it is a kind of compactification of X related to the metric d on it. Denote by BR(X) the set {y ∈ X\d(x,y) ... Higson have introduced the conception of "Higson’s corona" (see [1]). For a given metric space X, it is a kind of compactification of X related to the metric d on it. Denote by BR(X) the set {y ∈ X\d(x,y) < R}. Recall that a slowly oscillating function on X is a function f G C*(X) satisfying the following condition: 展开更多
关键词 Stone-Cech corapactification Higson compactification coarse equivalent
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Resolvable Spaces and Compactifications
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作者 Monerah Al-Hajri Karim Belaid 《Advances in Pure Mathematics》 2013年第3期365-367,共3页
This paper deals with spaces such that their compactification is a resolvable space. A characterization of space such that its one point compactification (resp. Wallman compactification) is a resolvable space is given.
关键词 RESOLVABLE SPACE Alexandroff compactification Wallman compactification
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A&zeta;x- and Open <i>C<sub>D</sub><sup>*</sup></i>-Filters Process of Compactifications and Any Hausdorff Compactification
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作者 Hueytzen J. Wu Wan-Hong Wu 《Advances in Pure Mathematics》 2012年第4期296-300,共5页
By means of a characterization of compact spaces in terms of open CD*-filters induced by a , a - and open CD*-filters process of compactifications of an arbitrary topological space Y is obtained in Sec. 3 by embedding... By means of a characterization of compact spaces in terms of open CD*-filters induced by a , a - and open CD*-filters process of compactifications of an arbitrary topological space Y is obtained in Sec. 3 by embedding Y as a dense subspace of , YS = {ε |ε is an open CD*-filter that does not converge in Y}, YT = {A|A is a basic open CD*-filter that does not converge in Y}, is the topology induced by the base B = {U*|U is open in Y, U ≠φ} and U* = {F∈Ysw (or YTw)|U∈F}. Furthermore, an arbitrary Hausdorff compactification (Z, h) of a Tychonoff space X?can be obtained from a by the?similar process in Sec.3. 展开更多
关键词 Net OPEN FILTER OPEN CD*-Filter Base Basic OPEN CD*-Filter OPEN CD*-Filter -Filter x-Filter Tychonoff Space Normal T1-Space Compact Space compactificationS Stone-Cech compactification Wallman compactification
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Proof That Spatial Transitions Release/Absorb Energy That Compactification Necessarily Leads to Changes in Volume, Energy and Entropy
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第2期310-320,共11页
Using simple box quantization, we demonstrate explicitly that a spatial transition will release or absorb energy, and that compactification releases latent heat with an attendant change in volume and entropy. Increasi... Using simple box quantization, we demonstrate explicitly that a spatial transition will release or absorb energy, and that compactification releases latent heat with an attendant change in volume and entropy. Increasing spatial dimension for a given number of particles costs energy while decreasing dimensions supplies energy, which can be quantified, using a generalized version of the Clausius-Clapyeron relation. We show this explicitly for massive particles trapped in a box. Compactification from N -dimensional space to (N - 1) spatial dimensions is also simply demonstrated and the correct limit to achieve a lower energy result is to take the limit, Lw → 0, where Lw is the compactification length parameter. Higher dimensional space has more energy and more entropy, all other things being equal, for a given cutoff in energy. 展开更多
关键词 SPATIAL TRANSITIONS Box Quantization compactification
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An Expository on Some Nonstandard Compactifications
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作者 Alagu Somasundaram Rukhmoni Kala 《Advances in Pure Mathematics》 2021年第10期807-815,共9页
Three classical compactification procedures are presented with nonstandard flavour. This is to illustrate the applicability of Nonstandard analytic tool to beginners interested in Nonstandard analytic methods. The gen... Three classical compactification procedures are presented with nonstandard flavour. This is to illustrate the applicability of Nonstandard analytic tool to beginners interested in Nonstandard analytic methods. The general procedure is as follows: A suitable equivalence relation is defined on an enlargement <sup>*</sup><em>X </em>of the space <em>X</em> which is a completely regular space or a locally compact Hausdorff space or a locally compact Abelian group. Accordingly, every <em>f</em> in <em>C</em>(<em>X</em>,<em>R</em>) (the space of bounded continuous real valued functions on <em>X</em>) or <em>Cc</em>(<em>X</em>,<em>R</em>) (the space of continuous real valued functions on <em>X</em> with compact support) or the dual group <span style="white-space:nowrap;">&#915; </span>of the locally compact Abelian group <em>G</em> is extended to the set <img alt="" src="Edit_b9535172-924d-44f0-bab3-c49db17a3b7a.png" /> of the above mentioned equivalence classes. A compact topology on <img alt="" src="Edit_9d7962a3-b8a3-4693-b62a-078c8c4b4853.png" /> is obtained as the weak topology generated by these extensions of <em>f</em>. Then <em>X</em> is naturally imbedded densely in <img alt="" src="Edit_f7d403b2-eff3-4555-b8e7-1b106e06d2e7.png" />. 展开更多
关键词 Non-Standard compactification Completely Regular Space Locally Compact Hausdorff Space Locally Compact Abelian Group
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QUOTIENT SPACE OF LMC-COMPACTIFICATION AS A SPACE OF z-FILTERS
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作者 Mohammad Akbari Tootkaboni 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期2010-2020,共11页
The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological semigroup.In this paper an internal construction of a quotient space of the left multiplicative cont... The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological semigroup.In this paper an internal construction of a quotient space of the left multiplicative continuous compactification of a semitopological semigroup is constructed as a space of z-filters 展开更多
关键词 LMC-compactification z-filters quotient space
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More Compactification for Differential Systems
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作者 Harry Gingold Daniel Solomon 《Advances in Pure Mathematics》 2013年第1期190-203,共14页
This article is a review and promotion of the study of solutions of differential equations in the “neighborhood of infinity” via a non traditional compactification. We define and compute critical points at infinity ... This article is a review and promotion of the study of solutions of differential equations in the “neighborhood of infinity” via a non traditional compactification. We define and compute critical points at infinity of polynomial autonomuos differential systems and develop an explicit formula for the leading asymptotic term of diverging solutions to critical points at infinity. Applications to problems of completeness and incompleteness (the existence and nonexistence respectively of global solutions) of dynamical systems are provided. In particular a quadratic competing species model and the Lorentz equations are being used as arenas where our technique is applied. The study is also relevant to the Painlevé property and to questions of integrability of dynamical systems. 展开更多
关键词 Nonlinear Polynomial compactification Ultra Extended Euclidean Space CRITICAL POINT Equilibrium POINT CRITICAL POINT at INFINITY CRITICAL Direction at INFINITY BASIN of Divergence BASIN of Convergence Ideal Solutions Asymptotic Stability Global Globally Asymptotically Stable Jacobian Painleve Analysis Competing Species Model Lorenz Equations Periodic Surface Differential Geometry Attractor REPELLER
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A Modified Wallman Method of Compactification
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作者 Hueytzen J.Wu Wan-Hong Wu 《Advances in Pure Mathematics》 2013年第6期590-597,共8页
Closed and basic closed C*D-filters are used in a process similar to Wallman method for compactifications of the topological spaces Y, of which, there is a subset of C*(Y) containing a non-constant function, where C*(... Closed and basic closed C*D-filters are used in a process similar to Wallman method for compactifications of the topological spaces Y, of which, there is a subset of C*(Y) containing a non-constant function, where C*(Y) is the set of bounded real continuous functions on Y. An arbitrary Hausdorff compactification (Z,h) of a Tychonoff space X can be obtained by using basic closed C*D-filters from in a similar way, where C(Z) is the set of real continuous functions on Z. 展开更多
关键词 Closed █_(x)-Filter Open and Closed C^(*)_(D)-Filter Bases Basic Open and Closed C^(*)_(D)-Filters compactification Stone-Cech and Wallman compactifications
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Inverse Faraday effect of weakly relativistic full Poincaré beams in plasma
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作者 Wei Liu Qing Jia Jian Zheng 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2023年第1期43-52,共10页
The inverse Faraday effect(IFE),which usually refers to the phenomenon in which a quasi-static axial magnetic field is self-generated when a circularly polarized beam propagates in a plasma,has rarely been studied for... The inverse Faraday effect(IFE),which usually refers to the phenomenon in which a quasi-static axial magnetic field is self-generated when a circularly polarized beam propagates in a plasma,has rarely been studied for lasers with unconventional polarization states.In this paper,IFE is reconsidered for weakly relativistic full Poincarébeams,which can contain all possible laser polarization states.Starting from cold electron fluid equations and the conservation of generalized vorticity,a self-consistent theoretical model combining the nonlinear azimuthal current and diamagnetic current is presented.The theoretical results show that when such a laser propagates in a plasma,an azimuthally varying quasi-static axial magnetic field can be generated,which is quite different from the circularly polarized case.These results are qualitatively and quantitatively verified by three-dimensional particle-in-cell simulations.Our work extends the theoretical understanding of the IFE and provides a new degree of freedom in the design of magnetized plasma devices. 展开更多
关键词 poincarÉ WEAKLY FARADAY
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A Inherent Characterization of L-fuzzy Compactification
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作者 孟培源 周武能 《湖北科技学院学报》 1994年第1期1-9,共9页
AInherentCharacterizationofL-fuzzyCompactification¥Mengpeiyuan(XianningTeachers'College,Hubei,China)Zhouwune... AInherentCharacterizationofL-fuzzyCompactification¥Mengpeiyuan(XianningTeachers'College,Hubei,China)Zhouwuneng(YunyangTeacher... 展开更多
关键词 α-ultra-closed filter Nice-compactness T_(1)-seperation L-fuzzy topological space compactification
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基于Euler-poincare方程高效率的机械多体系统动力学建模
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作者 郝永江 李炳志 王爽 《现代信息科技》 2023年第24期147-151,156,共6页
伪速度的引入导致了拉氏方程的广义化,使得通过欧拉-庞卡莱方程建立多体系统的动力学模型,实现了动力学的全局描述,并保持了潜在理论结构和拉氏方程的优点。并且其惯量矩阵相对简单,对于完整或非完整约束系统都适用。空间算子代数中的... 伪速度的引入导致了拉氏方程的广义化,使得通过欧拉-庞卡莱方程建立多体系统的动力学模型,实现了动力学的全局描述,并保持了潜在理论结构和拉氏方程的优点。并且其惯量矩阵相对简单,对于完整或非完整约束系统都适用。空间算子代数中的移位算子结合了关联矩阵、通路矩阵和低序体阵列的特点,而且形式更简单,更容易在计算机上实现,最重要的是它包含了运动学和动力学递推关系。将其引入动能函数的计算,提高了效率,避免了重复计算、交叉运算。最后给出了算例及仿真。 展开更多
关键词 伪速度 欧拉-庞卡莱方程 移位算子 高效率 动力学模型
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Poincaré级数判定法中齐次解的存在性问题
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作者 蒋逸卿 刘姗姗 申屠梦灵 《大学数学》 2023年第1期120-125,共6页
进一步发现利用傅里叶级数的方法,通过补充若干细节,仍然可以给出Poincaré级数法的完整论证.
关键词 poincaré级数法 傅里叶级数 齐次解
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旋转行波型超声电机定子的非线性动力学分析
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作者 陶征 赵丹 高建设 《机械设计与制造》 北大核心 2024年第2期210-213,共4页
超声电机作为一种新型电机,独特的性能使其在如太空探索、精密仪器等一些特殊领域有着广阔的应用前景。然而,超声电机的强机电耦合非线性特性使其在工作过程中往往会产生频率漂移、跳跃等非线性现象,从而影响电机工作的稳定性。用四阶Ru... 超声电机作为一种新型电机,独特的性能使其在如太空探索、精密仪器等一些特殊领域有着广阔的应用前景。然而,超声电机的强机电耦合非线性特性使其在工作过程中往往会产生频率漂移、跳跃等非线性现象,从而影响电机工作的稳定性。用四阶Runge-Kutta法、Lyapunov指数、Poincaré截面等方法获得了旋转行波超声电机定子在单相激励下的非线性振动响应特性,研究了定子振动响应的Hopf分岔以及由Hopf分岔通向周期解的变化过程,该结果对进一步改善行波型超声电机输出特性的研究具有一定的参考意义。 展开更多
关键词 超声电机 非线性动力学 HOPF分岔 poincarÉ截面
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Poincare映射的数值算法及其在永磁同步电机混沌分析中的应用 被引量:30
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作者 张波 李忠 +1 位作者 毛宗源 庞敏熙 《控制理论与应用》 EI CAS CSCD 北大核心 2001年第5期796-800,共5页
给出了Poincare映射的一个数值算法 ,并在提出的永磁同步电机 (PMSM )混沌模型的基础上 ,应用Poincare映射分析了PMSM的混沌现象 .仿真结果表明Poincare映射可以更直观地反映其相应的状态空间图形 ,而从一个新的角度证实了PMSM的混沌运... 给出了Poincare映射的一个数值算法 ,并在提出的永磁同步电机 (PMSM )混沌模型的基础上 ,应用Poincare映射分析了PMSM的混沌现象 .仿真结果表明Poincare映射可以更直观地反映其相应的状态空间图形 ,而从一个新的角度证实了PMSM的混沌运动的存在性 . 展开更多
关键词 poincarE映射 永磁同步电机 混沌 数值算法
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基于Poincare变换的滑动轴承非线性油膜力数据库方法 被引量:34
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作者 孟志强 徐华 朱均 《摩擦学学报》 EI CAS CSCD 北大核心 2001年第3期223-227,共5页
运用状态空间 Poincare变换使径向滑动轴承动力系统的部分状态变量由无限区间变换到有限区间 .在经过变换的状态空间中求解 Reynolds方程 ,建立了径向滑动轴承非线性油膜力数据库及相应的插值拟合程序 ,实现了非线性油膜力的快速准确获... 运用状态空间 Poincare变换使径向滑动轴承动力系统的部分状态变量由无限区间变换到有限区间 .在经过变换的状态空间中求解 Reynolds方程 ,建立了径向滑动轴承非线性油膜力数据库及相应的插值拟合程序 ,实现了非线性油膜力的快速准确获得 .通过滑动轴承 -转子系统运动瞬态分析和 展开更多
关键词 滑动轴承 非线性油膜力 poincare变换 数据库
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心率的Poincare散点图量化指标 被引量:16
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作者 徐征 葛霁光 +1 位作者 徐秋萍 张辉 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2000年第4期433-436,共4页
Poincare散点图是非线性研究的重要方法之一 ,它可以有效地描述吸引子的形状 ,以往的研究大多停留在图形样式的角度上 ,这给研究带来了描述上的不确定和应用上的不便。因此我们在散点图图形基础上提取出四个定量参数 ,它们是散点图面积... Poincare散点图是非线性研究的重要方法之一 ,它可以有效地描述吸引子的形状 ,以往的研究大多停留在图形样式的角度上 ,这给研究带来了描述上的不确定和应用上的不便。因此我们在散点图图形基础上提取出四个定量参数 ,它们是散点图面积、长轴、短轴和角度。并根据心率的散点图特点 ,研究出较有效的“龟爬行计数法”将四个定量参数在计算机上得以实现。将四个定量参数应用于临床冠脉病变患者的心率变异研究上 ,发现这四个定量参数可以很好地描述散点图 ,也具有一定的特异性 ,提示这有很好的临床应用价值。 展开更多
关键词 心率 poincarE散点图 定量参数
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心率变异性Poincare散点图分析与BIS对麻醉深度监测的相关性研究 被引量:12
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作者 李佩 申岱 +1 位作者 贾晓宁 诸葛万银 《临床麻醉学杂志》 CAS CSCD 北大核心 2011年第2期116-118,共3页
目的观察全身麻醉时心率变异性分析中散点图分析和脑电双频指数(BIS)的变化,探讨散点图分析和BIS在监测麻醉深度时的相关性。方法选择ASAⅠ或Ⅱ级择期手术患者28例,测定手术前一天(T1)、麻醉诱导前(T2)、诱导插管(T3)、手术开始1h(T4)... 目的观察全身麻醉时心率变异性分析中散点图分析和脑电双频指数(BIS)的变化,探讨散点图分析和BIS在监测麻醉深度时的相关性。方法选择ASAⅠ或Ⅱ级择期手术患者28例,测定手术前一天(T1)、麻醉诱导前(T2)、诱导插管(T3)、手术开始1h(T4)、苏醒时(T5)、术后1d(T6)6个时点各5min的HR、MAP、散点图的短轴(SD1)、长轴(SD2)的变化以及T2~T5时BIS变化。结果与T1时比较,T6时MAP、SD2明显下降(P<0.05)。与T2时比较,T3时HR明显增快、MAP、SD2明显升高(P<0.01);T4、T5时MAP、SD2明显下降(P<0.05或P<0.01);T3~T5时BIS、SD1明显下降(P<0.01)。结论心率变异性非线性分析SD1能描述围术期心脏自主神经功能状态的变化,与反应麻醉镇静程度的BIS有很好的相关性。 展开更多
关键词 poincarE散点图 脑电双频指数 全身麻醉 心率变异性
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采用周期轨Poincaré映射的非线性电力电子系统小干扰稳定性分析 被引量:6
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作者 王刚 范学鑫 +2 位作者 付立军 纪锋 马海鑫 《中国电机工程学报》 EI CSCD 北大核心 2012年第1期84-92,14,共9页
拓扑结构切换、占空比控制方法和非线性元件均可使电力电子系统具有非线性特性,因此其小干扰稳定问题属于微分方程周期轨的稳定问题。由于状态空间平均法误差较大、难以预测分叉,而数值仿真法物理概念不清晰,因此,提出了基于梯形积分法... 拓扑结构切换、占空比控制方法和非线性元件均可使电力电子系统具有非线性特性,因此其小干扰稳定问题属于微分方程周期轨的稳定问题。由于状态空间平均法误差较大、难以预测分叉,而数值仿真法物理概念不清晰,因此,提出了基于梯形积分法的非线性电力电子系统周期轨稳定性分析方法。利用梯形积分法描述系统占空比方程和每阶段的非线性状态方程,由隐函数求导法和链式求导法计算周期轨Poincaré映射的雅可比(Jacobian)矩阵,提出了系统稳定裕度指标,建立了基于周期轨Poincaré映射的非线性电力电子系统小干扰稳定性分析方法。该方法能够克服小干扰稳定传统分析方法的困难,揭示非线性电力电子系统失稳的动力系统机制。仿真分析验证了算法的有效性。 展开更多
关键词 非线性电力电子系统 小干扰稳定性 周期轨 poincarÉ映射
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