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平面变压器的寄生参数是平面变压器结构设计以及电源电路设计的重要参考指标.由于寄生参数与平面变压器的结构、材料等存在非线性关系,寄生参数非常难以计算.针对现有的寄生参数预测算法以及寄生参数的特点,设计了一种基于离散二进制粒子群优化随机森林的平面变压器寄生参数预测模型.通过36组平面变压器数据对该模型进行训练和验证,结果显... 相似文献
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建立了一种含离散变量的电力系统无功优化的非线性互补约束模型,并提出相应的现代内点非线性互补算法。该方法先将变压器抽头和电容器组数等离散变量按连续化处理,进行无功优化计算,快速寻求离散变量的两界;用所得结果作为初始解,以离散变量的两界构造其互补约束条件。该方法有效地解决了传统方法求解离散量存在的时间与精度之间的矛盾,可精确求解无功优化中可调变压器抽头和可调电容器组别。经多个测试系统的计算结果表明,算法具有收敛性好、计算迅速的特点,能有效地解决含离散变量的大规模电力系统无功优化问题,满足在线运行的需要。 相似文献
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为提高基于变压器绕组等效电路计算的频率响应分析(FRA)曲线与真实绕组测量FRA曲线的一致性,本文针对一个变压器绕组实验室模型,利用多种优化算法对其等效电路参数进行优化,实现变压器绕组等效电路的准确建模。首先,基于经典变压器集总参数等效电路模型,根据节点电压矩阵算法,推导该模型的频率响应曲线计算公式,获得该绕组模型的FRA曲线。其次,基于仿真数据,利用六种优化算法得到等效电路参数的优化结果并对比,实现三种优化算法的预筛选。再次,针对多个变压器绕组模型,将选出的三种优化算法分别应用于绕组等效电路参数优化中,以适度函数值及参数偏移量最小、实测曲线与等效电路仿真曲线间的相似度最大及偏差度最小为指标,确定最佳的参数优化算法。最后,针对选出的最优算法,研究不同迭代次数对优化结果的影响,通过对比选择出最优的迭代次数,获得最优的等效电路参数,并据此建立最终的变压绕组等效电路模型。本文研究成果可为提高基于变压器绕组等效电路的FRA曲线计算准确性提供参考。 相似文献
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介绍了高频低造型电源变压器的计算机辅助设计。当给定设计参数诸如变换器后扑、输入输出电压、输出功率、变压器效率等后,此程序便会自动搜索满足设计的体积最小的变压器。设计者可根据具体要求,调整设计参数,以达到最为满意的设计结果。 相似文献
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介绍了遗传算法的基本原理及算法步骤,对其编码与解码方案、约束条件的处理、搜索速度、全局寻优等进行了改造,使新群体的整体素质更好,加快了寻优过程。采用改进的遗传算法对干式变压器的电磁计算设计进行了优化,并应用于SGB-800/10干式电力变压器的单目标和双目标的优化设计。通过实例参数对比分析,表明该算法切实可行,优化效果较好。 相似文献
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基于参数辨识的变压器保护原理需要对变压器绕组参数进行精确辨识。文章推导出双绕组单相和双绕组三相变压器的参数辨识方程,而后提出一种新的参数辨识算法,最小二乘法和粒子群优化算法相结合的混合算法,可以实现对变压器绕组参数的精确辨识。通过Matlab/Simulink进行仿真,仿真算例验证了该混合算法的可行性。该算法具有较好的应用前景。 相似文献
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开关磁阻电动机驱动系统混合离散规划的研究 总被引:1,自引:0,他引:1
开关磁阻电动机驱动(SRD)系统的优化设计问题是一个带多个约束条件的非线性规划,而且变量的取值具有离散性,本文重点对SRD系统的离散(混合离散)规划问题进行了研究,并提出了一种适合于离散规划的模式搜索法改进方案,针对优化中约束条件众多且非线性程度高的特点,提出了一种可行点加速寻找方法;同时,就计算工作量庞大问题也提出了有效的措施。 相似文献
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A design algorithm for gearless elevator winches with a frequency-controlled electric drive is developed on the basis of discrete programming. The cost-optimal winch design is determined. 相似文献
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Yuen‐Hong Alvin Ho Hing‐Kit Kwan Ngai Wong Ka‐Leung Ho 《International Journal of Circuit Theory and Applications》2009,37(3):453-472
We present a design methodology for globally optimizing the topologies of delta–sigma modulators (DSMs). Previous work cast the design task into a general non‐convex, nonlinear programming problem, whereas we propose to recast it as a signomial programming problem. Convexification strategies are presented for transforming the signomial programming problem into its equivalent convex counterpart, thereby enabling the solution of globally optimal design parameters. It is also possible to include circuit non‐ideal effects that affect the transfer function of the modulator into the formulation without affecting the computational efficiency. The proposed framework has been applied to topology synthesis problems of single‐loop and multi‐loop low‐pass DSMs based on discrete‐time circuitry. Numerical results confirm the effectiveness of the proposed approach over conventional nonlinear programming techniques. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Mingtian Fan Kenichi Aoki Akimine Nishikori Koichi Nara 《Electrical Engineering in Japan》1992,112(1):114-123
This paper presents a new algorithm to solve an optimal power flow problem which can take into consideration the discrete nature of some facilities in power systems. The optimal power flow problem is formulated as a nonlinear mixed-integer programming problem in which the number of transformer taps and the number of shunt capacitor units and reactor units are treated as discrete variables. This paper attempts to solve such a large-scale nonlinar mixed-integer programming problem by some effective programming techniques. The optimization procedure of the algorithm is that the nonlinear mixed-integer programming problem is linearized iteratively and solved by an approximation method for linear mixed-integer programming. A fundamental feature of the algorithm is that it can guarantee a solution which is discrete, feasible and near-optimal. The validity and efficiency of the algorithm is demonstrated by the numerical results of real-scale optimal power flow problems. 相似文献
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土石方调配问题是水利水电工程设计和施工中一个重要问题,传统解决方法包括线性规划、大系统分解协调、动态规划等,存在一定的局限性。本文尝试运用强化学习中离散型Q学习的方法解决土石方调配问题。文中探讨了土石方调配问题Q学习模型的构建及解法,并通过一个工程实例,验证了本文提出方法的可行性。为后续利用强化学习方法解决动态土石方调配平衡的研究奠定了基础。 相似文献
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本文对电机优化设计中的离散变量问题和总极值问题进行了研究。指出电机优化设计具有普遍意义和更为有效的处理方法应归结为混合规划总极值问题。本文在研究混合规化总极值的弃舍算法的基础上,提出了适合于电机优化设计的新的弃舍策略和易于在微型计算机上实现的最优性条件。本文对一台大型水轮发电机进行了优化设计并验证了算法。 相似文献
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梯级水电站长期优化调度的细粒度并行离散微分动态规划方法 总被引:3,自引:0,他引:3
伴随水电规模的扩大,水电站群优化调度的计算量不断增加,需要探求新的方法.在分析离散微分动态规划(discrete differentiation and dynamic programming,DDDP)算法的基础上,提出了基十分治模式的梯级水电站长期优化调度的细粒度并行离散微分动态规划(parallel discrete differentiation and dynamic programming,PDDDP)方法,并以澜沧江梯级的6个电站系统长期优化调度问题为应用实例,在多核计算环境下进行验证.结果表明,多核环境下的PDDDP方法简便易行,能充分利用闲置计算资源、大幅度提高优化调度的计算效率,是解决大规模复杂水电系统调度的高效和实用方法. 相似文献
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《Electric Power Systems Research》2002,62(3):215-224
Unit commitment with ramping constraints is a very difficult problem with significant economic impact. A new method is developed in this paper for scheduling units with ramping constraints within Lagrangian relaxation framework based on a novel formulation of the discrete states and the integrated applications of standard dynamic programming for determining the optimal discrete states across hours, and constructive dynamic programming for determining optimal generation levels. A section of consecutive running or idle hours is considered as a commitment state. A constructive dynamic programming (CDP) method is modified to determine the optimal generation levels of a commitment state without discretizing generation levels. The cost-to-go functions, required only for a few corner points with a few continuous state transitions at a particular hour, are constructed in the backward sweep. The optimal generation levels can be obtained in the forward sweep. The optimal commitment states across the scheduling horizon can then be obtained by standard dynamic programming. Numerical testing results show that this method is efficient and the optimal commitment and generation levels are obtained in a systematic way without discretizing or relaxing generation levels. 相似文献
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