基于差分进化算法的Wiener模型辨识

DE算法是一类基于种群的启发式全局搜索技术,该算法原理简单,控制参数少,鲁棒性强,具有良好的优化性能.利用差分进化算法对Wiener模型参数进行辨识,把辨识问题等价为以估计参数为优化变量的非线性极小值优化问题,并分析了算法中种群规模NP、缩放因子F、交叉概率CR等控制参数对辨识过程中的全局并行搜索能力和收敛速度的影响,以保证算法的全局收敛性.对Wiener模型的数值仿真结果表明了DE算法在参数辨识问题中的有效性,以及较PSO算法更强的非线性系统辨识能力.     

基于差分进化算法的Wiener模型辨识

DE算法是一类基于种群的启发式全局搜索技术,该算法原理简单,控制参数少,鲁棒性强,具有良好的优化性能.本文利用差分进化算法对Wiener模型参数进行辨识,把辨识问题等价为以估计参数为优化变量的非线性极小值优化问题,并分析了算法中种群规模NP、缩放因子F、交叉概率CR等控制参数对辨识过程中的全局并行搜索能力和收敛速度的影响,以保证算法的全局收敛性.对Wiener模型的数值仿真结果表明了DE算法在参数辨识问题中的有效性,以及较PSO算法更强的非线性系统辨识能力。     

基于自适应云粒子群算法的Wiener模型辨识

针对非线性系统Wiener模型的系统辨识问题,提出一种基于自适应云模型的粒子群优化(ACMPSO)算法的辨识方法。ACMPSO算法利用云模型实现优秀粒子的遗传和进化操作,根据进化状况动态调整云模型的参数,自适应地控制云模型算法的寻优范围和精度,有较强的全局搜索和局部求精能力。仿真实验证明该算法寻优精度高于其他主要PSO算法;将该算法应用于Wiener模型的系统辨识,通过实验证明了该辨识方法优于当前其他方法。     

采用改进PSO的非线性系统T-S模糊模型辩识

提出了一种新的T-S模糊模型的非线性系统辨识方法。采用自适应模糊C均值聚类算法确定模糊模型的前件结构及参数,用改进的粒子群优化(PSO)算法来辩识模糊模型的结论参数以获得系统参数的最优估计。仿真结果表明该方法是有效的。     

基于改进粒子群算法的Hammerstein模型辨识

提出辨识非线性Hammerstein模型的新方法。将非线性系统的辨识问题转化为参数空间上的函数优化问题,采用粒子群算法获得该优化问题的解。为了进一步增强粒子群优化算法的辨识性能,提出采用速度变异粒子群对整个参数空间进行搜索得到系统参数的最优估计。仿真结果验证了该方法的有效性。     

一种改进粒子群算法及其在Wie ne r模型辨识中的应用

针对标准粒子群算法收敛速度较慢、收敛精度较低、容易陷入局部最优等方面的缺点,提出一种融合细菌觅食算法和鲶鱼效应的混合粒子群算法。通过四个经典测试函数仿真实验,验证了该算法具有较其他改进方法更强的全局搜索能力、收敛速度和收敛精度。并针对一类可描述成Wiener模型的工业过程进行了参数辨识,通过数值仿真验证了混合粒子群算法的实用性以及较其他算法更强的非线性辨识能力。     

基于头脑风暴优化算法的Wiener模型参数辨识

Wiener模型是一种典型的模块化非线性模型,广泛应用于工业过程控制领域.由于其结构的非线性,参数辨识无法直接得到解析解.为此,将Wiener模型的参数估计转化为带约束的非线性优化问题,以头脑风暴优化(BSO)算法并行搜索该问题的最优解,并以搜索过程中的反馈信息调整BSO算法的变异过程,以改进算法的收敛速度和辨识精度.数值仿真和工业数据验证了所提算法的有效性.     

基于PSO算法的变差函数球状模型参数拟合

对一阶变差函数球状模型及其二阶套合结构的参数拟合进行研究,利用粒子群优化(PSO)算法在求解非线性优化问题时收敛的快速性以及全局寻优的有效性等优势,将待拟合球状模型的参数组合为一个粒子向量,在PSO算法迭代过程中对部分粒子进行混合柯西-高斯变异,实现变差函数球状模型最优参数的自动拟合。仿真实验结果表明,该方法操作简单、可靠性高。     

基于正态云的粒子群优化算法及其应用

为辨识非线性系统Hammerstein模型,将非线性系统的辨识问题转化为参数空间上的优化问题,提出一种基于正态云模型的改进粒子群算法(NCPSO)。该算法采用动态变异概率,对全局最优粒子和粒子自身最优位置进行正态云变异,以产生新的粒子引导种群的飞行,有效避免早熟收敛。采用一种广义学习策略,提升粒子向最优解飞行的概率,将NCPSO算法用于对Hammerstein模型的辨识,相比其他算法,该算法辨识精度较高。     

应用改进粒子群算法辨识Hammerstein模型

研究非线性系统辨识问题.针对非线性系统中单输入单输出Hammerstein模型,由于传统辨识方法对Hammerstein模型中非线性部分具有不易辨识的缺陷,造成辨识精度低、辨识效果差等问题.为此,在基本粒子群算法的基础上,提出了一种带有收缩因子的改进的粒子群算法对非线性系统进行辨识的方法,可将参数辨识问题转换为参数空间上的函数优化问题,然后利用粒子群算法的并行搜索能力进行参数寻优.通过MATLAB软件进行仿真,并与基本粒子群算法进行比较,结果表明,利用改进算法不仅提高了辨识精度而且获得了良好的辨识效果,从而验证了算法的有效性和可行性.     

一种辨识Wiener-Hammerstein模型的新方法

针对非线性Wiener-Hammerstein模型,提出利用粒子群优化算法对非线性模型进行辨识的新方法.该方法的基本思想是将非线性系统的辨识问题转化为参数空间上的优化问题;然后采用粒子群优化算法获得该优化问题的解.为了进一步增强粒子群优化算法的辨识性能,提出利用一种混合粒子群优化算法.最后,仿真结果验证了该方法的有效性和可行性.     

PSO算法在非线性回归模型参数估计中的应用

非线性回归模型的参数估计是较为困难的寻优问题,经典方法常会陷入局部极值。由于粒子群算法是一种有效的解决优化问题的群集智能算法,它的突出特点是操作简便、容易实现且全局搜索功能较强,故将粒子群优化算法用于非线性系统模型参数估计,并通过对6种非线性回归模型的参数估计进行了验证。实验结果表明：粒子群优化算法是一种有效的参数估计方法。     

Correlation analysis method based SISO neuro-fuzzy Wiener model

A novel identification algorithm for neuro-fuzzy based single-input-single-output (SISO) Wiener model with colored noises is presented in this paper. The separable signal is adopted to identify the Wiener model, leading to the identification problem of the linear part separated from nonlinear counterpart. Then, the correlation analysis method can be employed for identification of linear part. Moreover, in the presence of random signal, the least square method based parameters estimation algorithm of static nonlinear part are proposed to avoid the impact of colored noise. As a result, proposed method can circumvent the problem of initialization and convergence of the model parameters encountered by the existing iterative algorithms used for identification of Wiener model. Examples are used to verify the effectiveness of the proposed method.     

Identification of wiener model with discontinuous nonlinearities using differential evolution

This paper deals with the identification of Wiener models with discontinuous nonlinearities. The identification of the Wiener model is formulated as an optimization problem. Differential evolution algorithm, a powerful and robust evolutionary algorithm, is used to search the optimal parameter of the Wiener model such that the error between the output of true model and that of the identified model is minimized. The proposed method can identify the parameters of linear dynamic subsystems and static nonlinear function of the Wiener model simultaneously, and overcome the difficulty of unavailability of the intermediated signal. Two application examples verify that the proposed method can accurately estimate the parameters of the Wiener model even in a low SNR environment.     

A PWA model identification method based on optimal operating region partition with the output-error minimization for nonlinear systems

When piecewise affine (PWA) model-based control methods are applied to nonlinear systems, the first question is how to get sub-models and corresponding operating regions. Motivated by the fact that the operating region of each sub-model is an important component of a PWA model and the parameters of a sub-model are strongly coupled with the operating region, a new PWA model identification method based on optimal operating region partition with the output-error minimization for nonlinear systems is initiated. Firstly, construct local data sets from input-output data and get local models by using the least square (LS) method. Secondly, cluster local models according to the feature vectors and identify the parameter vectors of sub-models by weighted least squares (WLS) method. Thirdly, get the initial operating region partition by using a normalized exponential function, which is to partition the operating space completely. Finally, simultaneously determine the optimal parameter vectors of sub-models and the optimal operating region partition underlying the output-error minimization, which is executed by particle swarm optimization (PSO) algorithm. Simulation results demonstrate that the proposed method can improve model accuracy compared with two existing methods.     

基于粒子群优化算法的非线性系统模型参数估计

非线性模型的参数估计是较为困难的寻优问题,经典方法常会陷入局部极值。由于粒子群算法是一种有效的解决优化问题的群集智能算法,它的突出特点是操作简便、容易实现且全局搜索功能较强,故将粒子群优化算法用于非线性系统模型参数估计,并通过对3种典型的非线性模型的参数估计进行了验证。实验结果表明：粒子群优化算法参数估计精度高,是一种有效的参数估计方法。     

Integral sliding mode based optimal composite nonlinear feedback control for a class of systems

This paper presents an optimization method of designing the integral sliding mode （ISM） based composite nonlinear feedback （CNF） controller for a class of low order linear systems with input saturation. The optimal CNF control is first designed as a nominal control to yield high tracking speed and low overshoot. The selection of all the tuning parameters for the CNF control law is turned into a minimization problem and solved automatically by particle swarm optimization （PSO） algorithm. Subsequently, the discontinuous control law is introduced to reject matched disturbances. Then, the optimal ISM-CNF control law is achieved as the sum of the optimal CNF control law and the discontinuous control law. The effectiveness of the optimal ISM-CNF controller is verified by comparing with a step by step designed one. High tracking performance is achieved by applying the optimal ISM-CNF controller to the tracking control of the micromirror.     

Nonlinear inertia weight variation for dynamic adaptation in particle swarm optimization

The particle swarm optimization (PSO) is a relatively new generation of combinatorial metaheuristic algorithms which is based on a metaphor of social interaction, namely bird flocking or fish schooling. Although the algorithm has shown some important advances by providing high speed of convergence in specific problems it has also been reported that the algorithm has a tendency to get stuck in a near optimal solution and may find it difficult to improve solution accuracy by fine tuning. The present paper proposes a new variation of PSO model where we propose a new method of introducing nonlinear variation of inertia weight along with a particle's old velocity to improve the speed of convergence as well as fine tune the search in the multidimensional space. The paper also presents a new method of determining and setting a complete set of free parameters for any given problem, saving the user from a tedious trial and error based approach to determine them for each specific problem. The performance of the proposed PSO model, along with the fixed set of free parameters, is amply demonstrated by applying it for several benchmark problems and comparing it with several competing popular PSO and non-PSO combinatorial metaheuristic algorithms.