基于GAPSO和自抗扰控制的稀土永磁同步电机性能研究

针对稀土永磁同步电机控制系统存在强耦合、非线性、抗干扰能力差的问题，提出了一种基于遗传粒子群算法（GAPSO）的稀土永磁同步电机自抗扰控制方法。第一步，介绍研究背景并推导出稀土永磁同步电机的数学表达式；第二步，通过设计跟踪微分器、扩张状态观测器以及非线性状态误差方程推导出自抗扰控制器的数学表达式，并利用遗传粒子群算法对其进行优化；第三步，讨论基于GAPSO和自抗扰控制的稀土永磁电机转速性能情况。通过Simulink仿真验证了上述方法的有效性，说明本文设计的自抗扰控制方法对提高电机性能具有促进作用。     

球磨机制粉系统的线性自抗扰控制

球磨机制粉系统具有大惯性、大时滞和强耦合等特点,很难建立精确的数学模型.本文分析了球磨机制粉系统的动态特性,并为其设计分散线性自抗扰控制方案.该方案综合分散控制和线性自抗扰控制器的优点,结构简单,不依赖于对象精确模型,可以对被控对象中存在的耦合、干扰和不确定性等进行估计并补偿.根据实际现场要求,对球磨机制粉系统进行设定值跟踪实验、输入扰动实验和性能鲁棒性实验,并比较所设计方案与PID方案的控制性能.结果表明,分散线性自抗扰控制具有更强的解耦能力和抗干扰能力,且性能鲁棒性更优.      

冷轧机轧辊偏心的自抗扰重复补偿控制

针对冷轧机由于轧辊偏心扰动引起出口厚度波动问题,提出一种轧辊偏心自抗扰重复补偿控制策略。首先设计改进型重复控制器对由轧制力反映出的偏心扰动信号进行高精度跟踪,从而在无需偏心扰动信号数学模型的条件下获得偏心补偿信号;然后设计自抗扰控制器改善重复控制器的稳定性和鲁棒性,同时对轧辊偏心扰动进行快速补偿。仿真结果表明,所提出的控制方法在系统参数发生摄动及偏心信号发生变化的情况下,仍能够对轧辊偏心进行有效补偿。     

矿热炉电极调节系统的双闭环自抗扰控制

对矿热炉电极系统提出了一种自抗扰控制策略的控制方法。设计了一种不依赖于对象模型的电极自抗扰控制器,并对其参数进行了整定,自抗扰控制器的扩张状态观测器可以实时观测系统状态和扩张状态,从而实现全状态反馈及系统不确定性和外扰的补偿控制。该系统与传统的单闭环恒流控制系统比较,增加了电极位置环。仿真实验表明,该控制系统不仅具有较强的鲁棒性,对内外干扰具有较强的抑制能力,更具有较优的动态性能。     

一种线性自抗扰控制器参数自整定方法

针对线性自抗扰控制器参数难于整定的问题,提出了一种基于动态响应过程时序数据挖掘的参数自整定算法.算法以线性自抗扰控制器中线性误差反馈律的两个增益信号回路的动态响应为参数调整对象,通过改进变收缩系数的随机搜索算法进行参数整定,记录动态响应过程数据,基于关联关系挖掘得到控制参数调整策略应用于线性自抗扰控制器的参数自整定.为验证本文提出的参数自整定方法的实际效果,以液压自动位置控制系统为控制对象,分别采用阶跃响应仿真和Monte Carlo实验进行对比研究.结果表明,基于数据挖掘参数自整定的线性自抗扰控制器动态响应较好,鲁棒性较强,改进了变收缩系数随机搜索算法调整时间较长以及传统线性自抗扰控制器超调较大的缺点,是一种具有实用性的线性自抗扰控制器参数自整定方法.      

无人直升机自抗扰自适应轨迹跟踪混合控制

为满足无人直升机高精度轨迹跟踪的控制需求,并降低直升机动力学模型误差对飞行控制器飞行控制效果产生的影响,提出自抗扰自适应直升机混合控制.该控制器的内环控制采用模型跟随自适应控制,通过使用动量反向传播算法(MOBP)对该内环控制参数进行实时优化.通过使用自抗扰控制(ADRC)对直升机的水平速度进行控制.仿真结果表明,该混合控制器能够实现直升机对预定轨迹的跟踪.相对PID和级联ADRC控制,该控制器具有更好的抗扰性和鲁棒性.通过在200 kg级的专业植保无人直升机XV-2上搭载所提出的控制器,使其自主飞行轨迹跟踪控制的均方根误差在0.6 m以内.      

基于时变局部模型的无人驾驶车辆路径跟踪

目前常用于无人驾驶车辆路径跟踪控制的有模型控制方法有两类，一类是基于全局模型的控制方法，另一类是基于局部模型的控制方法。基于全局模型的路径跟踪控制中无人驾驶车辆的纵向速度与全局坐标系中的横向、纵向位移误差之间存在随航向角变化的耦合关系，这种耦合关系使得控制器无法将纵向速度作为控制输入来提高路径跟踪控制的精确性。基于局部模型的路径跟踪控制器通常采用误差模型作为参考模型，这种模型使得控制器在参考路径曲率变化幅度较大时精确性较低。针对前述问题，基于非线性模型预测控制滚动优化的原理，提出一种基于时变局部模型的无人驾驶车辆路径跟踪控制方法，并在低速高附着路面、低速低附着路面和高速低附着路面等工况下进行仿真验证。在仿真结果中，相比于基于全局模型的路径跟踪控制器、基于局部模型的路径跟踪控制器以及Stanley路径跟踪控制器，基于时变局部模型的路径跟踪控制器精确性更高，其位移误差绝对值不超过0.3342 m，航向误差绝对值不超过0.0913 rad。      

热连轧活套系统的自适应自抗扰控制研究

在热连轧活套系统工作点附近建立了活套高度与张力的近似线性化耦合模型。用两个并行自抗扰控制器对活套系统进行解耦与控制,用单神经元方法对自抗扰控制器的重要参数进行在线修正以提高控制器的自适应性。仿真结果显示了本文算法的可行性与有效性。     

基于LADRC的双机架铝带冷连轧机张力控制研究

针对某公司1 850 mm双机架铝带冷连轧机架间张力控制系统具有参数多变、强干扰等特点以及存在传统PID控制鲁棒性较差的问题,建立速度-张力控制系统数学模型,设计了基于线性自抗扰算法的张力控制器。Matlab仿真结果表明,与传统PID张力系统相比,采用线性自抗扰控制技术的张力闭环系统具有更好的动态性能、抗干扰能力和鲁棒性。     

基于滑模控制的矿井提升机变频控制系统

针对老式矿井提升机采用直接转矩控制策略存在的缺陷,提出了一种新的改进型控制方案:引入滑模控制器代替传统的磁链、转矩控制器来产生参考电压矢量,并通过空间电压矢量控制策略合成该电压矢量.仿真实验和结果表明,同传统控制方案相比,新型改进方案减小了转矩脉动和电流畸变,系统控制性能得到改善.     

Stability Characteristics for Transport Aircraft Response to Clear-Air Turbulence

The clear-air turbulence is difficult to detect and predict and yet affects the flight safety the most. A transport aircraft in encountering a severe turbulence frequently develops a sudden plunging motion with the abrupt change in altitude. The aerodynamic forces and moments involved are dynamic and nonlinear and are not well known. The main objective in the present paper is to present the dynamic and nonlinear aerodynamics estimated with the flight data recorder data of a transport aircraft through a fuzzy-logic algorithm. The algorithm is utilized to establish a thrust model and aerodynamic models for all aerodynamic coefficients including the effects of turbulence. The static and dynamic stability derivatives for the subject transport aircraft are demonstrated to be highly nonlinear and unsteady in response to a severe clear-air turbulence in transonic flight.     

基于模糊神经解耦控制的板型板厚控制系统仿真

面对板型板厚控制这一复杂、多变量耦合的非线性系统,本文提出了一种两级串联结构的模糊神经网络解耦控制策略,前级为自调整模糊控制器,后级为基于动态耦合特性的自适应神经网络解耦控制器,并从理论上证明了学习算法的收敛性。实现了无模型板型板厚综合控制。仿真结果表明,该控制系统收敛性好、抗干扰性强,取得令人满意的板型板厚控制精度。     

集总干扰下六旋翼飞行器的轨迹跟踪控制

针对复杂集总干扰下六旋翼飞行器轨迹跟踪控制问题,给出了混合积分反步法控制与线性自抗扰控制的控制算法. 首先,通过牛顿-欧拉方程建立六旋翼飞行器的非线性动力学模型,并剖析系统输入输出的数学关系. 其次,根据六旋翼飞行器动力学模型的特点,将其分为位置与姿态两个控制环. 位置环采用积分反步法控制理论设计控制器,通过引入积分项来提高系统的抗干扰能力,消除轨迹跟踪的静态误差;姿态环采用线性自抗扰控制技术设计控制器,通过线性扩张观测器估计和补偿集总干扰影响,提高系统的鲁棒性. 最后,通过2组仿真算例和1组飞行试验验证了本文所提飞行控制算法的有效性. 研究结果表明:该控制算法对集总干扰有较好的抑制作用,能够使六旋翼飞行器既快又稳地跟踪上参考轨迹,具有一定的工程应用价值.      

Qigong and L-1 straining maneuver oxygen system requirements with and without positive pressure breathing

Based on the characteristics of respiration and the intrathoracic pressure in Qigong (Q-G) maneuvering, it has been theorized that the Q-G maneuver may lessen the lack of coordination between aircraft oxygen apparatus and anti-G maneuvers and may be more compatible with positive pressure breathing (PPB). In an experiment intended to test this hypothesis, 5 male volunteers, trained in Q-G and L-1 maneuvers, performed the Q-G and the L-1 maneuvers without and with (PPB) at 4 and 6 kPa, respectively, with 14 respiratory parameters being measured. The results demonstrated that, when performing Q-G maneuver, the maximal expiratory flow rate averaged 1.175-1.645 L.s-1, the inspiratory peak flow, 1.003-1.297 L.s-1. Both these values were markedly lower than those of the L-1 maneuver, and matched well the performance of current aircraft oxygen apparatus. From the blood pressure and heart rate values, it is evident that PPB can further promote the blood pressure-raising effect of the Q-G maneuver, and alleviate pilots' fatigue.     

Flutter of a Swept Aircraft Wing with a Powered Engine

The flutter analysis of swept aircraft wings carrying a powered engine is presented. Because of the powered engine, both concentrated engine mass and the thrust force terms are combined in the governing equations which are obtained using Hamilton’s principle. Heaviside and Dirac delta functions are used to precisely consider the location and properties of the engine mass and the thrust force. The wing performs as a classical beam; and the structural model, which incorporates bending-torsion flexibility, is used. Also, Peter’s unsteady aerodynamic pressure loadings are considered and modified to take the sweep effects into account. The Galerkin method is subsequently applied to convert the partial differential equations into a set of ordinary differential equations. Moreover, the numerical results are compared with published results and excellent agreement is observed. Numerical simulations indicating the significant effects of the sweep angle, the thrust and the design parameters such as the mass ratio and the engine attached locations on the flutter boundaries are presented.     

Nonlinear Aeroelasticity: Continuum Theory, Flutter/Divergence Speed, and Plate Wing Model

This paper formulates flutter/divergence instability problems using continuum models for structure and air flow as coupled nonlinear partial differential equations. The structure model is a Kirchoff CFFF thin plate allowing for nonzero thickness and camber bending. The aerodynamics is modeled by the transonic small disturbance potential equation. The aeroelastic boundary conditions are derived for nonzero angle of attack. A central result is the time domain model as a nonlinear convolution/evolution equation in a Hilbert space. Flutter speed is characterized as a Hopf bifurcation point, completely determined by the linearized equations. The main tool in solving the linear equations is the Possio equation for nonzero angle of attack. Divergence speed is shown to be determined by an eigenvalue problem for linear operators. The corresponding stationary (steady state) solutions are more regular in the transonic range (as M goes to one) if the angle of attack is nonzero.     

Aeroelastic Analysis of Bridges: Effects of Turbulence and Aerodynamic Nonlinearities

Current linear aeroelastic analysis approaches are not suited for capturing the emerging concerns in bridge aerodynamics introduced by aerodynamic nonlinearities and turbulence effects. These issues may become critical for bridges with increasing spans and/or with aerodynamic characteristics sensitive to the effective angle of incidence. This paper presents a nonlinear aerodynamic force model and associated time domain analysis framework for predicting the aeroelastic response of bridges under turbulent winds. The nonlinear force model separates the aerodynamic force into low- and high-frequency components according to the effective angle of incidence. The low-frequency force component is modeled utilizing quasi-steady theory. The high-frequency force component is based on the frequency dependent unsteady aerodynamic characteristics, which are similar to the traditional force model but vary in space and time following the low-frequency effective angle of incidence. The proposed framework provides an effective analysis tool to study the influence of structural and aerodynamic nonlinearities and turbulence on the bridge aeroelastic response. The effectiveness of this approach is demonstrated by utilizing an example of a long span suspension bridge with aerodynamic characteristics sensitive to the angle of incidence. The influence of mean wind angle of incidence on the aeroelastic modal properties and the associated aeroelastic response and the sensitivity of bridge response to nonlinear aerodynamics and low-frequency turbulence are examined.