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1.
In spectrum analysis of induction motor current, the characteristic components of broken rotor bars(BRB) fault are often submerged by the fundamental component. Although many detection methods have been proposed for this problem, the frequency resolution and accuracy are not high enough so that the reliability of BRB fault detection is a ected. Thus, a new multiple signal classification(MUSIC) algorithm based on particle swarm intelligence search is developed. Since spectrum peak search in MUSIC is a multimodal optimization problem, an improved bare?bones particle swarm optimization algorithm(IBPSO) is proposed first. In the IBPSO, a modified strategy of subpopulation determination is introduced into BPSO for realizing multimodal search. And then, the new MUSIC algorithm, called IBPSO?based MUSIC, is proposed by replacing the fixed?step traversal search with IBPSO. Meanwhile, a simulation signal is used to test the e ectiveness of the proposed algorithm. The simulation results show that its frequency precision reaches 10~(-5), and the computational cost is only comparable to that of traditional MUSIC with 0.1 search step. Finally, the IBPSO?based MUSIC is applied in BRB fault detection of an induction motor, and the e ectiveness and superiority are proved again. The proposed research provides a modified MUSIC algorithm which has su cient frequency precision to detect BRB fault in induction motors.  相似文献   

2.
In spectrum analysis of induction motor current, the characteristic components of broken rotor bars (BRB) fault are often submerged by the fundamental component. Although many detection methods have been proposed for this problem, the frequency resolution and accuracy are not high enough so that the reliability of BRB fault detection is affected. Thus, a new multiple signal classification (MUSIC) algorithm based on particle swarm intelligence search is developed. Since spectrum peak search in MUSIC is a multimodal optimization problem, an improved bare-bones particle swarm optimization algorithm (IBPSO) is proposed first. In the IBPSO, a modified strategy of subpopulation determination is introduced into BPSO for realizing multimodal search. And then, the new MUSIC algorithm, called IBPSO-based MUSIC, is proposed by replacing the fixed-step traversal search with IBPSO. Meanwhile, a simulation signal is used to test the effectiveness of the proposed algorithm. The simulation results show that its frequency precision reaches 10?5, and the computational cost is only comparable to that of traditional MUSIC with 0.1 search step. Finally, the IBPSO-based MUSIC is applied in BRB fault detection of an induction motor, and the effectiveness and superiority are proved again. The proposed research provides a modified MUSIC algorithm which has sufficient frequency precision to detect BRB fault in induction motors.  相似文献   

3.
多峰值函数优化的改进粒子群算法   总被引:3,自引:0,他引:3  
多峰值函数优化中,基本粒子群算法进化后期收敛速度较慢,且可能出现最优解粒子在全局最优解附近“振荡”的现象,导致优化精度降低。为此,提出一种具有可控速度因子的改进粒子群算法。在完全随机、部分可控与完全可控三种速度调控策略下,对比研究几种具有不同变速特性的寻优轨迹下算法的精度及运算效率。试验结果表明,通过采用可控的寻优速度因子,优化性能得到改进,特别是采用完全控制策略,不仅可获得较高的优化精度,而且收敛速度更快,表现出更好的综合性能。  相似文献   

4.
郗涛  杨威振 《机械科学与技术》2022,41(12):1829-1838
针对齿轮箱的故障诊断的优化问题,提出了一种基于参数优化的变分模态分解(VMD)与卷积神经网络(CNN)相融合的故障诊断方法。该算法首先通过鲸鱼优化算法对VMD算法进行优化,之后通过正交实验法与粒子群优化算法进行了CNN模型中的重要参数进行优化,最后将分解后得到的固有模态分量输入CNN模型中进行训练学习。诊断完成后得到训练与检测结果,其中经过算法优化后CNN模型的训练与检测准确率可达98.7%与95.7%,优于未优化的准确率94.3%与91.8%。通过对结果的分析验证出该算法的可行性以及在诊断成功率方面的优越性,实现了故障特征信息的自适应性提取,并将故障类型进行分类,最终实现齿轮箱故障诊断的智能化。  相似文献   

5.
针对采用传统参数估计方法得到的模型拟合误差较大的问题,建立多重威布尔混合分布参数估计的非线性最小二乘模型,并提出基于模拟退火(SA)思想的自适应粒子群(PSO)算法进行求解。在PSO算法优化过程中,采用自适应方法调整惯性权重和加速因子,加快其收敛速度;引入模拟退火机制,根据Metropolis准则确定最优粒子的取舍,改善其全局搜索能力。将该方法应用到某型柴油机喷油器失效分布的参数估计中,并与图解法、基于Levenberg-Marquardt的非线性最小二乘法、标准PSO算法、自适应PSO算法求解的结果进行比较,分析所提方法的优化性能及精度。结果表明,该方法能够有效提高多重威布尔混合分布模型参数估计的精度和效率。  相似文献   

6.
陈文哲  汪镭 《机电一体化》2012,18(1):26-29,67
针对污水处理过程所具有的多变量、非线性和大时滞的特点,在污水生化反应过程中提出基于免疫粒子群的参数估计方法。在粒子群进化过程中,引入免疫算法机制,通过抗体与抗原的参数计算来促进或抵制抗体的进化,保证粒子群进化的多样性,指导粒子群的优化过程,克服粒子群算法的早熟现象,加快收敛速度和提高全局寻优能力,成功估计模型参数。应用免疫粒子群算法在各类工程模型确定中有较大的应用潜力。  相似文献   

7.
8.
粒子群算法在工程优化设计中的应用   总被引:17,自引:2,他引:15  
将粒子群算法与惩罚函数法相结合,建构一种离散粒子群算法,解决工程上非线性约束离散变量优化设计问题。为实现离散变量与连续变量的转化,构造了相应的扩张函数,提出惩罚因子的确定策略。通过容器设计算例验证,粒子群算法方法优于文献所列方法。应用粒子群算法、惩罚函数法及所提出的策略对波纹管工程实例进行优化设计,其单位重量下整体波纹管的补偿量比在用产品提高了79.96%,与理论解接近,进一步证明了离散粒子群算法及策略在处理工程非线性约束离散优化设计问题时的有效性,其为工程上类似优化设计提供借鉴。  相似文献   

9.
Current research in broken rotor bar (BRB) fault detection in induction motors is primarily focused on a high-frequency resolution analysis of the stator current. Compared with a discrete Fourier transformation, the parametric spectrum estimation technique has a higher frequency accuracy and resolution. However, the existing detection methods based on parametric spectrum estimation cannot realize online detection, owing to the large computational cost. To improve the efficiency of BRB fault detection, a new detection method based on the min-norm algorithm and least square estimation is proposed in this paper. First, the stator current is filtered using a band-pass filter and divided into short overlapped data windows. The min-norm algorithm is then applied to determine the frequencies of the fundamental and fault characteristic components with each overlapped data window. Next, based on the frequency values obtained, a model of the fault current signal is constructed. Subsequently, a linear least squares problem solved through singular value decomposition is designed to estimate the amplitudes and phases of the related components. Finally, the proposed method is applied to a simulated current and an actual motor, the results of which indicate that, not only parametric spectrum estimation technique.  相似文献   

10.
改进粒子群优化算法在工程优化问题中的应用研究   总被引:10,自引:1,他引:10  
粒子群优化(PSO)算法是一种群集智能方法,它通过粒子之间的合作与竞争以实现对多维复杂空间的高效搜索。在对于粒子群群体构造和粒子多样性对收敛速度和精度影响的研究基础上提出了一种改进型粒子群优化算法。针对工程中的有约束的优化问题,将改进粒子群算法与函数法相结合进行求解。计算实例表明改进型粒子群优化算法大大改善了传统PSO算法的全局收敛性能,解的精度提高了很多。  相似文献   

11.
针对微粒群算法易于陷入局部最优解、早熟的缺点,将Lévy飞行引入微粒速度迭代公式中,并动态改变微粒群速度迭代公式中Lévy飞行的权重值,提出动态Lévy飞行微粒群算法。根据T-S故障树理论,建立液压支架液压系统的可靠性模型,进而得出可靠性费用目标函数。将提出的动态Lévy飞行微粒群算法应用于液压支架液压系统的可靠性优化中,并通过标准微粒群算法、布谷鸟搜索算法和基于Lévy飞行微粒群算法比较,验证所提出算法的优越性。  相似文献   

12.
新的求解钻削路径优化问题算法研究   总被引:3,自引:1,他引:3  
将粒子群优化算法应用到离散空间的群孔钻削路径优化之中。由于基本粒子群算法不能保证全局或局部收敛,在算法数学模型的基础上,引入重新生成停止进化微粒的方式对算法加以改进,使改进的算法具有全局收敛能力。通过建立序交换元和序交换集对算法的操作算子进行改进,满足钻削路径优化问题中整数编码的需要。实验表明,新的算法具有实现简单,收敛速度快,能够实现全局收敛的优点。  相似文献   

13.
Assembly sequence planning (ASP) has always been an important part of the product development process, and ASP problem can usually be understood as to determine the sequence of assembly. A good assembly sequence can reduce the time and cost of the manufacturing process. In view of the local convergence problem with basic discrete particle swarm optimization (DPSO) in ASP, this paper presents a hybrid algorithm to solve ASP problem. First, a chosen strategy of global optimal particle in DPSO is introduced, and then an improved discrete particle swarm optimization (IDPSO) is proposed for solving ASP problems. Through an example study, the results show that the IDPSO algorithm can obtain the global optimum efficiently, but it converges slowly compared with the basic DPSO. Subsequently, a modified evolutionary direction operator (MEDO) is used to accelerate the convergence rate of IDPSO. The results of the case study show that the new hybrid algorithm MEDO-IDPSO is more efficient for solving ASP problems, with excellent global convergence properties and fast convergence rate.  相似文献   

14.
为了解决小波降噪软阈值选择非最优以及SVM算法中惩罚参数、核函数参数的设置问题,将小波变换、支持向量机分别与量子行为粒子群优化算法QPSO(quantum-behaved particle swarm optimization,)相结合,利用QPSO优化小波阈值以及优化SVM输入参数,进行全局寻优,并将之应用到滚动轴承故障识别中。实验中,QPSO-WT滤波后信号具有更高的信噪比和更低的MSE,QPS0-SVM对10种不同状态的轴承进行故障诊断,对于多分类的情况该方法的识别精确度达到了87.67%,与SVM和RBF神经网络对比,从而进一步证明了该方法的有效性,说明该方法能够满足实际工况下的故障诊断要求。  相似文献   

15.
在粒子群优化算法中,引入遗传算法中的克隆算子和变异算子,提出了粒子群遗传优化算法,并将多机器人系统的任务分配问题转换为在多维解空间内寻找最优解的问题,利用粒子群遗传优化算法在此空间寻找最优解,以实现对多机器人任务的协调分配.算例仿真表明,粒子群遗传优化算法不但具有粒子群优化算法所具有的易于工程实现、计算效率高等优点,还克服了粒子群优化算法易早熟、粒子群整体收敛性差等缺点,能够解决多机器人任务分配问题.  相似文献   

16.
针对小波神经网络常用的反向传播算法普遍存在收敛速度慢,容易陷入局部极小点,网络参数的选取只能凭实验和经验来确定等缺点,提出了一种基于遗传算法优化的小波神经网络并应用于齿轮的故障诊断。仿真结果表明,该方法充分的发挥了遗传算法的全局寻优能力,小波分析的非线性逼近能力和神经网络的自学习特性,优化了系统的收敛速度和故障诊断的精度。  相似文献   

17.
提出了一种滚动轴承故障诊断的新方法。首次将自适应最稀疏时频分析(ASTFA)方法应用于振动信号的降噪,并针对KVPMCD方法只选择一种最佳相关模型而忽略其他几种相关模型对预测精度贡献的缺陷,提出了一种改进的KVPMCD模式识别算法--人工鱼群算法优化融合Kriging模型的基于变量预测模型的模式识别(AKVPMCD)算法,即采用收敛速度快、鲁棒性强、具有全局寻优能力的人工鱼群智能算法(AFSIA)优化融合多种Kriging相关模型来提高模型预测精度。在此基础上,提出了一种基于ASTFA降噪和AKVPMCD算法的滚动轴承故障诊断方法。实验结果表明,该方法可以有效提高分类识别的精度。  相似文献   

18.
在地震模拟振动台控制系统中,常用三参量控制实现加速度信号控制,但目前三参量参数理论整定方法存在效果不佳、智能化程度不高等问题。针对三参量控制参数整定问题,提出一种基于粒子群算法的三参量控制参数整定算法,利用粒子群算法的寻优能力完成三参量参数整定研究。仿真结果显示,与理论值相比,粒子群算法自整定值控制下地震模拟振动台波形复现精度得到提高,表明粒子群算法实现地震模拟振动台三参量控制系统参数整定,算法有效。  相似文献   

19.
针对滚动轴承特征提取和故障识别两个关键环节,提出了一种广义复合多尺度加权排列熵(GCMWPE)与参数优化支持向量机相结合的故障诊断方法。利用GCMWPE全面表征滚动轴承故障特征信息,构建高维故障特征集。应用监督等度规映射(S-Isomap)算法进行有效的二次特征提取。采用天牛须搜索优化支持向量机(BAS-SVM)诊断识别故障类型。将所提方法应用于滚动轴承实验数据分析过程,结果表明:GCMWPE特征提取效果优于多尺度加权排列熵、复合多尺度加权排列熵和广义多尺度加权排列熵;GCMWPE与S-Isomap相结合的特征提取方法可在低维空间中有效区分滚动轴承不同故障类型;BAS-SVM的识别正确率和识别速度优于粒子群优化支持向量机、模拟退火优化支持向量机和人工鱼群优化支持向量机;所提方法能够有效、精准地识别出各故障类型。  相似文献   

20.
异构视觉传感网络的标定是实现准确行人检测、跟踪、识别以及行为分析的关键和前提,对公共安全和智能安防具有重要意义。本文提出了一种面向行人检测的异构视觉传感网络自适应标定方法。首先,构建主动旋转变焦(PTZ)传感节点变焦成像模型,采用基于SURF特征点匹配的方法实现内参数自标定。其次,构建外参数分布式标定模型,将异构视觉传感网络外参数标定分解为节点局部标定和网络全局标定,从而避免采用单一中心节点进行集中式处理,提高方法的可扩展性;最后,为了提高标定精度,采用自适应混沌微粒群优化算法最小化内、外参数估计的再投影误差和轨迹匹配误差。实验结果表明,本方法有效降低了网络通讯量和标定误差,提高了异构视觉传感网络行人检测精度,具有重要的理论和实际应用价值。  相似文献   

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