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Boundedness of Hausdorff operators on the power weighted Hardy spaces 被引量:3
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作者 CHEN Jie-cheng HE Shao-yong ZHU Xiang-rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期462-476,共15页
In this paper, we consider the two-dimensional Hausdorff operators on the power weighted Hardy space H;(R;) ( -1 ≤α≤0), defined by H;f(x)=∫R;Φ(u)f(A(u)x)du,where Φ∈L;oc;(R;),A(u) = (α;(u));is a... In this paper, we consider the two-dimensional Hausdorff operators on the power weighted Hardy space H;(R;) ( -1 ≤α≤0), defined by H;f(x)=∫R;Φ(u)f(A(u)x)du,where Φ∈L;oc;(R;),A(u) = (α;(u));is a 2×2 matrix, and each α;is a measurablefunction.We obtain that HΦ,A is bounded from H;(R;) ( -1≤α≤0) to itself, if∫R2|Φ(u)‖det A;(u)|‖A(u)‖;ln(1+‖A;(u)‖;/|det A;(u)|)du<∞.This result improves some known theorems, and in some sense it is sharp. 展开更多
关键词 Hausdorff operator Hardy space power weight
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Endpoint Estimates for Hardy Operator's Conjugate Operator with Power Weight on n-Dimensional Space 被引量:1
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作者 Xudong Nie Shimo Wang Dunyan Yan 《Analysis in Theory and Applications》 2013年第3期267-274,共8页
In this paper, we establish two integral inequalities for Hardy operator's conjugate operator at the endpoint on n-dimensional space. The operator Hn is bounded from Lxα1 (Gn) to Lxβq (Gn) with the bound explic... In this paper, we establish two integral inequalities for Hardy operator's conjugate operator at the endpoint on n-dimensional space. The operator Hn is bounded from Lxα1 (Gn) to Lxβq (Gn) with the bound explicitly worked out and the similar result holds for Hn*. 展开更多
关键词 Conjugate operator power weight endpoint estimate.
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LDPC-Coded OFDM Transmission Based on Adaptive Power Weights in Cognitive Radio Systems
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作者 Seyed Eman Mahmoodi Bahman Abolhassani 《International Journal of Communications, Network and System Sciences》 2011年第12期761-769,共9页
In this paper, we propose a new scheme to improve the performance of an LDPC-coded OFDM based cognitive radio (CR) link by applying adaptive power weights. To minimize estimation errors of detected signals in all the ... In this paper, we propose a new scheme to improve the performance of an LDPC-coded OFDM based cognitive radio (CR) link by applying adaptive power weights. To minimize estimation errors of detected signals in all the CR subcarriers, power weights are allocated to the CR subcarriers at the secondary transmitter. Some constraints for the power weights are considered, such as keeping the interference power introduced by the CR to primary users below a given interference threshold and also keeping sum of transmission powers in all CR subcarriers within a total transmission power. The LDPC decoder applies these power weights in the Log Likelihood Ratios (LLRs) used in message passing scheme at the secondary receiver to achieve more reliable communications. So, the received signal in each CR subcarrier will be decoded with the knowledge of transmission power weights, which come from the cognitive feedback channel without additional cost. Simulation results demonstrate that our proposed scheme achieves a lower bit error rate and a higher transmission rate compared with those of the same scheme without applying power weights. 展开更多
关键词 COGNITIVE RADIO OFDM LDPC Interference power weighting
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Explicit constants for Hardy’s inequality with power weight on n-dimensional product spaces 被引量:14
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作者 WANG ShiMo LU ShanZhen YAN DunYan 《Science China Mathematics》 SCIE 2012年第12期2469-2480,共12页
In this paper, Hardy operator H on n-dimensional product spaces G = (0, ∞)n and its adjoint operator H* are investigated. We use novel methods to obtain two main results. One is that we characterize the sufficient an... In this paper, Hardy operator H on n-dimensional product spaces G = (0, ∞)n and its adjoint operator H* are investigated. We use novel methods to obtain two main results. One is that we characterize the sufficient and necessary conditions for the operators H and H* being bounded from Lp(G, xα) to Lq(G, xβ), and the bounds of the operators H and H* are explicitly worked out. The other is that when 1 < p = q < +∞, norms of the operators H and H* are obtained. 展开更多
关键词 n-dimensional Hardy operator Hausdorff-Young inequality power weight
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L^2 NORM INEQUALITY WITH POWER WEIGHTS FOR THE MAXIMAL RIESZ SPHERICAL MEANS
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作者 陆善镇 《Chinese Science Bulletin》 SCIE EI 1986年第16期1087-1091,共5页
We have pointed out in [1] that so far the L^2 norm inequalities with power weights for the Riesz means σ_R~δ(g)(x) of multiple Fourier integrals have been obtained only by Hirschman and J. L. Rubio de Francia respe... We have pointed out in [1] that so far the L^2 norm inequalities with power weights for the Riesz means σ_R~δ(g)(x) of multiple Fourier integrals have been obtained only by Hirschman and J. L. Rubio de Francia respectively: 展开更多
关键词 L^2 NORM INEQUALITY WITH power weightS FOR THE MAXIMAL RIESZ SPHERICAL MEANS
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Generalizations of mixed weighted power mean inequality 被引量:1
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作者 马统一 张海娟 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期192-197,共6页
Tarnavas established mixed weighted power mean inequality in 1999. A separation of weighted power mean inequslity was derived in this paper. As its applications, some separations of other inequalities were given.
关键词 INEQUALITY power mean weighted power mean mixed weighted power mean difference function of mixed weightedpower mean separation
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INVERSE POWER METHOD AND WEIGHTED SOBOLEV SPACES
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作者 丁毅 《Acta Mathematica Scientia》 SCIE CSCD 1992年第1期7-21,共15页
1. Introduction This paper is a continuation of the paper [5]. Now we want to treat the problem
关键词 INVERSE power METHOD AND weightED SOBOLEV SPACES
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Properties, Inference and Applications of Inverse Power Two-Parameter Weighted Lindley Distribution 被引量:1
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作者 M. M. E. Abd El-Monsef H. S. Al-Kzzaz 《Open Journal of Statistics》 2020年第5期889-904,共16页
We proposed </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">a new extension of three</span><span style="font-family:Verda... We proposed </span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">a new extension of three</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">parametric distribution” called the inverse power two-parameter weighted Lindley (IPWL) distribution capable of modeling a upside-down bathtub hazard rate function. This distribution is studied to get basic structural properties such as reliability measures, moments, inverse moments and its related measures. Simulation studies </span><span style="font-family:Verdana;">are </span><span style="font-family:Verdana;">done to present the performance and behavior of maximum likelihood estimates of the IPWL distribution parameters. Finally, we perform goodness of fit measures and test statistics using a real data set to show the performance of the new distribution. 展开更多
关键词 weighted Lindley Distribution Inverse power Reverse Hazard Function Inverse Moments Goodness of Fit
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Differentiation degree combination weighting method for investment decision-making risk assessment in power grid construction projects 被引量:5
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作者 Yuan Chang Chenmiao Liu +4 位作者 Minghua Liu Wenxia Liu Zongqi Liu Heng Zhang Yan Zheng 《Global Energy Interconnection》 2019年第5期466-478,共13页
Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such proj... Power grid construction projects are distinguished by their wide variety,high investment,long payback period,and close relation to national development and human welfare.To improve the investment accuracy in such projects and effectively prevent investment risks,this paper proposes an investment optimization decision-making method for multiple power grid construction projects under a certain investment scale.Firstly,an in-depth analysis of the characteristics and development requirements of China’s power grid projects was performed.Thereafter,the time sequence and holographic method was adopted to conduct multi-dimensional,multi-perspective risk assessment of different parts of power grid projects,and a holographic risk assessment index system was developed.Moreover,an investment decision model considering the comprehensive risk based on combination weighting was developed according to the output and input of power grid construction projects.A new combination weighting optimization method that takes into account the investment willingness of enterprises was designed to improve the current weighting evaluation methods.Finally,the validity and applicability of the proposed evaluation method were verified by case examples. 展开更多
关键词 power GRID PROJECTS Risk assessment Time SEQUENCE Index system Combination weighting
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Apply the Double-Weight Neural Network to Dynamic Power Management
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作者 JIN Ji LU LU Hua-xiang WANG Shou-jue 《微计算机信息》 2009年第1期200-202,共3页
This paper expounds a data-fitting algorithm for the double-weight neural network,and presents a new algorithm for the system's power management on the base of that.The double-weight neural network learns knowledg... This paper expounds a data-fitting algorithm for the double-weight neural network,and presents a new algorithm for the system's power management on the base of that.The double-weight neural network learns knowledge from the past idle periods of the system,and predicts the lengths of the coming idle periods.As a result of that,the system can switch its running states and re- duce the power dissipation according to the predictive values.The results of the experiments prove that this algorithm shows a better performance in increasing the right rate of shutting down and reducing the power consumption than other traditional ones. 展开更多
关键词 计算机网络 动力管理 运算法则 网络技术
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Wide-Area Delay-Dependent Adaptive Supervisory Control of Multi-machine Power System Based on Improve Free Weighting Matrix Approach
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作者 Ziyong Zhang Zhijian Hu +3 位作者 Yukai Liu Yang Gao He Wang Jianglei Suo 《Energy and Power Engineering》 2013年第4期435-441,共7页
The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission ... The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission delays. The paper uses an LMI-based iterative nonlinear optimization algorithm to establish a method of designing state-feedback controllers for power systems with a time-varying delay. This method is based on the delay-dependent stabilization conditions obtained by the improved free weighting matrix (IFWM) approach. In the stabilization conditions, the upper bound of feedback signal’s transmission delays is taken into consideration. Combining theoriesof state feedback control and state observer, the ASC is designed and time-delay output feedback robust controller is realized for power system. The ASC uses the input information from Phase Measurement Units (PMUs) in the system and dispatches supplementary control signals to the available local controllers. The design of the ASC is explained in detail and its performance validated by time domain simulations on a New England test power system (NETPS). 展开更多
关键词 ADAPTIVE Supervisory Controller (ASC) DELAY-DEPENDENT Damping Control power Oscillation IFWM LMI Free weighting Matrix APPROACH TIME-VARYING Delay WAMS
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Dynamic Equivalent Method of Motor Loads for Power Systems Based on the Weighted
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作者 Bo Hong Hanmei Hu +1 位作者 Ting Chen Qinfeng Li 《Journal of Power and Energy Engineering》 2014年第4期416-422,共7页
Dynamic equivalence can not only largely reduce the system size and the computation time but also stress the dominant features of the system [1]-[3]. This paper firstly recommends the basic concept of dynamic equivale... Dynamic equivalence can not only largely reduce the system size and the computation time but also stress the dominant features of the system [1]-[3]. This paper firstly recommends the basic concept of dynamic equivalent and the status of both domestic and abroad development in this area. The most existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors. In addition, the existing polymerization method which is based on the frequency domain algorithm of induction electric machines parameters takes a long time to equivalent for the large system, then the new method based on the weighted is proposed. Then, the basic steps for dynamic equivalence with the weighted method are introduced as follows. At first, the clustering criterion of motor loads based on time domain simulation is given. The motors with similar dynamic characteristics are classified into one group. Then, the simplication of the buses of motors in same group and network is carried out. Finally, parameters of the equivalent motor are calculated and the equivalent system is thus obtained based on the weighted. This aggregation method is applied to the simple distribution system of 4 generators. Simulation results show that the method can quickly obtain polymerization parameters of generator groups and the aggregation model retains the dynamic performance of the original model with good accuracy, the active and reactive power fitting error is smaller as well. 展开更多
关键词 power System DYNAMIC EQUIVALENT INDUCTION Motors Parameter AGGREGATION The weightED Method
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WEIGHTED ESTIMATE FOR THE MULTILINEAR OSCILLATORY SINGULAR INTEGRAL OPERATORS 被引量:1
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作者 LiuMingju JiangYinsheng 《Analysis in Theory and Applications》 2005年第1期90-100,共11页
In this paper, the weighted Lp(Rn) boundedness for the multilinear oscillatory singular integral operators with polynomial phases is studied.
关键词 multilinear operator oscillatory integral Herz space power weight BMO
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Power图的性质及构造算法研究 被引量:15
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作者 吴壮志 杨钦 怀进鹏 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2001年第12期1057-1062,共6页
点集的 Power图是点集 Voronoi图的推广 ,特别适合用来解决涉及球 (圆 )的几何问题 .文中首先对 Power图的基本性质进行了几何化的证明 ;之后 ,研究了权为负数时对 Power图的影响 ,指出在 Power图的理论中允许权为负数 ,从而 Power图可... 点集的 Power图是点集 Voronoi图的推广 ,特别适合用来解决涉及球 (圆 )的几何问题 .文中首先对 Power图的基本性质进行了几何化的证明 ;之后 ,研究了权为负数时对 Power图的影响 ,指出在 Power图的理论中允许权为负数 ,从而 Power图可以应用到具有负权性质的领域 ;最后 ,给出了平面点集的 Power图的构造算法 ,该算法利用 Power图与正则三角化互为对偶的原理 ,在点集的正则三角化的基础上构造 Power图 ,同时给出了实例以说明算法的有效性 . 展开更多
关键词 带权Voronoi图 power Laguerre图 正则三角化 构造算法 计算机图形学
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一种用于深空网天线组阵的基于归一化权的Matrix-Free Power Method 被引量:3
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作者 赵晓明 冯恩信 姜家持 《遥测遥控》 2009年第4期15-20,共6页
对深空网天线组阵中的几种信号相关算法作简要介绍,重点研究无需形成矩阵的幂的方法——Matrix-Free Power Method。通过理论分析,提出一种改进算法,即基于归一化权的Matrix-Free Power Method。理论计算和软件仿真结果均表明,基于归一... 对深空网天线组阵中的几种信号相关算法作简要介绍,重点研究无需形成矩阵的幂的方法——Matrix-Free Power Method。通过理论分析,提出一种改进算法,即基于归一化权的Matrix-Free Power Method。理论计算和软件仿真结果均表明,基于归一化权的Matrix-Free Power Method信噪比合成性能略优于原Matrix-Free Power Method。 展开更多
关键词 深空探测 天线组阵 MATRIX-FREE power Method 权信噪比 归一化权
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三维精确power图的GPU并行计算
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作者 肖艳阳 李渭 徐少平 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2023年第12期1958-1965,共8页
power图(加权Voronoi图)的计算是计算机图形学和计算几何等领域的一项基础任务.针对求解三维power图的传统串行方法所需的时间成本较高,且现有并行算法所得结果为近似解,提出一种新颖的GPU并行计算方法.首先给出power图与高一维受限Voro... power图(加权Voronoi图)的计算是计算机图形学和计算几何等领域的一项基础任务.针对求解三维power图的传统串行方法所需的时间成本较高,且现有并行算法所得结果为近似解,提出一种新颖的GPU并行计算方法.首先给出power图与高一维受限Voronoi图的等价构造方法,将Voronoi图的无网格方法直接推广到power图的计算.因此,给定的加权种子点被置于更高一维空间中的一组方格内,据此快速搜索每个种子点的邻居关系,进而使用各个种子点与其若干个邻居的中垂面对各自的power胞元进行并行裁剪,以快速地获取三维空间中的精确power图.对比不同求解域下和5万个种子点的计算耗时,比现有方法具有超过3倍的加速比. 展开更多
关键词 power 加权Voronoi图 精确计算 并行计算 GPU
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Joint Subcarrier and Power Allocation for Multi-UAV Systems 被引量:5
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作者 Xin Guan Yang Huang Qingjiang Shi 《China Communications》 SCIE CSCD 2019年第1期47-56,共10页
This paper investigates subcarrier and power allocation in a multi-UAV OFDM system.The study considers a practical scenario,where certain subcarriers are unavailable for dynamic subcarrier allocation,on account of pre... This paper investigates subcarrier and power allocation in a multi-UAV OFDM system.The study considers a practical scenario,where certain subcarriers are unavailable for dynamic subcarrier allocation,on account of pre-allocation for burst transmissions.We first propose a novel iterative algorithm to jointly optimize subcarrier and power allocation,so as to maximize the sum rate of the uplink transmission in the multiUAV OFDM system.The key idea behind our solution is converting the nontrivial allocation problem into a weighted mean square error(MSE) problem.By this means,the allocation problem can be solved by the alternating optimization method.Besides,aiming at a lower-complexity solution,we propose a heuristic allocation scheme,where subcarrier allocation and transmit power allocation are separately optimized.In the heuristic scheme,closedform solution can be obtained for power allocation.Simulation results demonstrate that in the presence of stretched subcarrier resource,the proposed iterative joint optimization algorithm can significantly outperform the heuristic scheme,offering a higher sum rate. 展开更多
关键词 MULTI-UAV OFDM SUBCARRIER ALLOCATION power ALLOCATION ALTERNATING optimization weighted MSE
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基于幂加权最小二乘拟合的红外相机辐射定标方法 被引量:1
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作者 金占雷 晋利兵 +3 位作者 张九双 徐丽娜 鲍云飞 李岩 《光子学报》 EI CAS CSCD 北大核心 2024年第4期171-186,共16页
分析了现有线性度计算方法的不足,提出基于偏差/测量值的新线性度评价方式,通过该方式最小二乘拟合的低端温度偏差比高端大一个数量级,并采用加权拟合提高系统响应线性度。在分析不同光谱的温度和辐亮度拟合函数基础上,提出一种基于辐... 分析了现有线性度计算方法的不足,提出基于偏差/测量值的新线性度评价方式,通过该方式最小二乘拟合的低端温度偏差比高端大一个数量级,并采用加权拟合提高系统响应线性度。在分析不同光谱的温度和辐亮度拟合函数基础上,提出一种基于辐亮度倒数幂加权最小二乘线性拟合的地面和星上辐射定标方法,确认最佳权重幂次,建立了幂次n=1的加权最小二乘拟合外黑体线性定标方程、内黑体线性定标方程、内外黑体辐亮度转换模型。针对星上内黑体高精度两点定标建立了基于加权最小二乘拟合内外黑体辐亮度转换模型;针对星上黑体发射率退化提出了基于恒星定标的红外相机星上内黑体辐亮度定标修正方法,建立了外黑体辐亮度、内黑体辐亮度和恒星辐亮度转换模型。采用加权线性拟合后,积分时间10 ms的低温端外黑体反演偏差由1.63 K下降到0.52 K,内黑体偏差反演温度偏差由0.83 K下降到0.39 K,系统响应线性度明显提升。 展开更多
关键词 红外遥感 辐射定标 线性度 幂加权 最小二乘拟合
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Randomly Weighted Averages on Order Statistics
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作者 Homei Hajir Hasanzadeh Leila Mina Ghasemi 《Applied Mathematics》 2013年第9期1340-1346,共7页
We study a well-known problem concerning a random variable uniformly distributed between two independent random variables. Two different extensions, randomly weighted average on independent random variables and random... We study a well-known problem concerning a random variable uniformly distributed between two independent random variables. Two different extensions, randomly weighted average on independent random variables and randomly weighted average on order statistics, have been introduced for this problem. For the second method, two-sided power random variables have been defined. By using classic method and power technical method, we study some properties for these random variables. 展开更多
关键词 Two-Sided power MOMENT weightED AVERAGES power DISTRIBUTION
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采用改进MPC提高储能系统电压暂态特性研究 被引量:1
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作者 鲍建 杨沛豪 《电源学报》 CSCD 北大核心 2024年第2期242-249,共8页
储能系统通过换流器实现并网运行,常规换流器因为其开关频率低,在采样、计算环节存在延时导致储能系统暂态特性差,甚至引起整个电网不稳定。本文采用模型预测控制MPC(model predictive control)来实现储能系统功率快速响应,避免延时影... 储能系统通过换流器实现并网运行,常规换流器因为其开关频率低,在采样、计算环节存在延时导致储能系统暂态特性差,甚至引起整个电网不稳定。本文采用模型预测控制MPC(model predictive control)来实现储能系统功率快速响应,避免延时影响。引入功率权重价值函数在有功、无功MPC控制中,计算储能换流器输出电压最优值。针对因为滤波电感参数偏移导致的MPC模型不准确问题,本文采用电感误差补偿控制来提高模型精度。通过Matlab/Simulink仿真和实验来验证本文所提方案可提高储能系统暂态特性,有效消除误差对MPC控制性能的影响。 展开更多
关键词 储能系统 暂态特性 模型预测控制 功率权重价值函数 电感误差电压补偿
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