数字控制的电磁轴承系统的研究

本文介绍了电磁轴承系统的数字控制器的组成及基本工作原理,建立了数字控制器的等效传递函数。对数控电磁轴承系统进行了起浮仿真及频域分析。在此基础上选取了控制器参数并进行了实验,实现了１６ｋｇ水平转子的稳定起浮和高速旋转,转速超过１２,０００ｒ／ｍｉｎ。     

转子──电磁轴承系统性能研究

本文介绍了电磁轴承的特性及其研究发展状况，给出了五自由度电磁轴承──转子系统模型，阐述了使转子稳定悬浮和运转的基本控制规律，分析了转子在电磁轴承中运转特性，并给出了转子稳定运转的实验记录曲线。     

电磁轴承μ鲁棒控制

为解决电磁轴承系统建模不确定性问题,建立径向电磁轴承的鲁棒控制模型.提出以结构奇异值作为优化指标的μ鲁棒控制器设计方法,通过引入虚拟不确定块将电磁轴承控制系统的鲁棒性能问题转化为广义系统的鲁棒稳定问题求解,兼顾系统的稳定鲁棒性和性能鲁棒性,减小设计的保守性.借助于Matlab仿真工具给出并比较电磁轴承控制系统不同情况下H∞控制和μ控制的仿真波形.研究结果表明:在允许摄动范围内基于μ综合的电磁轴承鲁棒控制对模型不确定性具有很好的动态特性、稳定鲁棒性和性能鲁棒性.     

基于扩充临界比例系数法的电磁轴承数字PID控制器参数整定

通过对电磁轴承系统的原理介绍,建立了电磁轴承数字控制系统模型,同时介绍了电磁轴承数字PID控制系统,采用MATLAB系统的工具箱对电磁轴承的控制系统建立数字和模拟两种模型并进行仿真,得到仿真结果,依据仿真结果研究了数字PID控制器参数对电磁轴承控制系统的影响,应用基于系统临界震荡的闭环整定方法的扩充临界比例系数法对数字PID控制器参数进行整定,得出较理想的仿真结果,为今后电磁轴承数字控制系统的设计提供了一种简洁高效的方法。     

磁浮轴承的控制和动态过程研究

建立了磁浮轴承的近似非最小相位传递函数模型，并基于此模型设计了保证系统稳定的闭环控制器。通过控制系统仿真对控制器参数进行了整定，分析了在不同扰动下转子的位移变化、电磁力和刚度的变化以及转子在高速时失控的原因，探讨了控制器参数与电磁轴承刚度及运转稳定性之间的变化关系。     

转子支承系统中的向心电磁轴承结构设计

讨论了向心电磁轴承的主要结构形式、决定轴承系统性能的主要参数的选取原则、轴承定子与转子结构参数的设计方法，并给出设计实例；通过对实例模型的两维静态场分析，验证和校正了结构设计过程中的假设条件和设计结果；给出了关于向心电磁轴承结构设计的较系统和精确的设计方法。     

电磁轴承刚度阻尼自动测试

针对电磁轴承刚度阻尼难以测量的问题,设计一套电磁轴承刚度阻尼测试系统,实现电磁轴承刚度、阻尼的自动测量.该系统激振器由自行研制的LabVIEW测试系统产生,电磁轴承传感器作为拾振器,自行研制的测量分析系统作为测量分析工具.给出电磁轴承的刚度和阻尼测量结果.根据本系统获得的电磁轴承支承转子的刚度、阻尼特性,对控制器的优化设计以及转子模型的优化设计有一定的指导意义.由于电磁轴承具有可控刚度和阻尼特性,因此可利用等效刚度和等效阻尼概念选择控制系统参数,简化设计过程.对实验室的样机台架进行具体分析,证实这种方法可行.分析结果还表明,若控制参数选择合理,将获得令人满意的减振效果.     

基于LQR理论的电磁轴承控制系统鲁棒稳定性分析

线性最优控制理论中采用的数学模型与实际物理模型总存在一定的差异，据此设计的控制参数不一定能满足实际系统稳定性的需要。针对这一问题，提出了一种分析线性最优控制系统鲁棒稳定界限的方法，并将其应用在基于LQR理论的电磁轴承控制系统的鲁棒稳定性分析中。结果表明：电磁轴承控制系统对模型矩阵摄动的鲁棒性在参数α确定时仅与加权矩阵Q、R的相对大小有关；选择较小的参数α和相对于加权矩阵R较大的Q阵、传感器采取外侧安装方式有利于提高电磁轴承控制系统对模型矩阵摄动的鲁棒性。此结论为主动电磁轴承控制器的设计和结构的设计提供了一定的理论依据。     

电磁轴承动刚度的自动测量

针对电磁轴承动刚度难以测量的问题,构建了一套简单的刚度测量系统用来自动测量电磁轴承的动刚度。该系统采用电磁轴承的数字控制器、功放、电磁铁作为激振器,电磁轴承的电涡流传感器作为拾振器,自行研制的测量分析系统作为测量分析工具。给出电磁轴承动刚度的测量结果。测量结果表明,该系统能较准确测量电磁轴承的动刚度。此测量系统还可以用于其他轴承刚度的测量,也可用于系统辨识。     

非线性径向主动电磁轴承-转子系统的耦合动力学特性及稳定性

研究径向主动电磁轴承支承的不对称转子系统的动力行为及稳定性。转子模型中考虑了陀螺效应，结合分散PID(pmponional integral differential)控制器方程和转子运动方程，形成系统方程。将预估—校正机理和Newton-Raphson方法相结合，给出一种径向主动电磁轴承—转子系统线性失稳转速即Hopf分岔点所对应转速的计算方法。基于打靶法及将预估—校正机理和打靶法相结合形成的一种轨迹预测追踪的延续算法，研究系统非线性不平衡周期响应及稳定性边界。结合Floquet分岔理论研究随系统控制参数改变径向主动电磁轴承—转子系统周期运动的局部稳定性和分岔行为。     

电磁式作动器及其振动主动控制系统的研究

本文以旋转机械为研究对象，成功地研制了一种电磁式作动器及其振动主动控制系统，解决了信号检测，控制，放大以及数据通讯等一此关键性的难题，利用该系统，对转子的不平衡振动进行了主动控制实验，取得取较好的控制效果。     

Study on the deformation mechanism for forming shafts without concavity during the near-net forming cross wedge rolling process

Intelligent robotic welding involves replicating the role of a manual professional welder to adaptively control the welding process. This is necessary to achieve accurate, fast and high-quality welding process in addition to the challenging factors for humans to operate in the welding environment. Therefore, robotic welding exists since the early days of robotics and it is still an active research area. This is why there have been numerous researches in this area for a very long time. Among various techniques proposed by researchers for the adaptive control of the robotic welding process, vision-based control is the most popular due to its non-invasiveness. Therefore, in this paper, we review, analyse and categorise the proposed vision-based techniques with the aim of covering the different image processing and feature extraction aspect of the techniques. The focus is mainly on the active vision system where various image processing techniques have been utilised in extracting the welding seam features. The challenges and difficulties to extract seam features in active vision system have been highlighted. The trends and new approaches have been indicated in order to provide a comprehensive source for researchers who are planning to carry out research related to the intelligent robot vision techniques for welding automation.     

Synthesis of control system and control algorithm for compensating for the residual imbalance of a complex flexible rotor on electromagnetic suspension

A system and algorithm for controlling a complex flexible rotor on active magnenic bearings have been proposed that make it possible to significantly reduce the amplitude of rotor vibrations at critical frequencies. The algorithm combines the identification of the forces of inertia caused by the residual imbalance and the formation of control actions compensating these forces. The effectiveness of the synthesized control system and control algorithm has been illustrated by computer simulation.     

四轮转向汽车的动力学控制现状及展望

综述四轮转向汽车的控制策略及其特点,讨论各种控制理论和控制方法在四轮转向汽车动力学控制中的应用。四轮转向系统能够有效地改善汽车的侧向动力学特性,提高汽车的主动性。认为将四轮转向系统珉春他主动底盘控制系统有机地结合起来,发挥各自优点,是四轮转向汽车的发展方向。     

管道有源消声实验系统的阻抗控制研究

以声阻抗为控制目标，对管道有源消声实验系统的消声机理进行了分析和探讨，研究表明，有源消声的效果取决于次级扬声器位置的等效声阻抗以及管道的阻抗分布特性，在消声实验台的自适应控制结果表明，在主频上取得了降噪40dB以上的效果。     

双层隔振系统主动控制的建模与仿真

针对双层隔振系统多自由度耦合振动的特性,采用隔振对象与中间质量的相对位移作为检测量,提出了一种双层隔振主动控制系统模型,并在M atlab/S imu link中建立相应功能模块,完成了双层隔振主动控制系统的仿真分析。仿真结果表明:该模型可有效实施振动控制。     

基于TMS320F2812的并联型有源电力滤波器

电力电子技术的迅速发展,使得电力网中的非线性负载元件的数量越来越多,而这些非线性负载又是电网谐波的主要来源,谐波会给电网带来严重的污染,使谐波的含量降低到规定的范围之内是现代电力行业迫切需要解决的一个问题。在治理谐波的领域中,有源电力滤波器已经走在了时代的最前列。该文以数字处理器芯片TMS320F2812为核心设计的有源电力滤波器控制系统,补偿电流的计算是通过瞬时无功功率理论的计算方法来实现的。首先在MATLAB环境中搭建有源电力滤波器的仿真模型,得出可行性的分析结果。接着设计了基于TMS320F2812的并联型有源电力滤波器控制系统的硬件和软件结构,通过在样机上试用的结果表明,在技术上是完全可行的。     

Development of a lane departure monitoring and control system

The lane departure avoidance systems have been considered promising to assist human drivers in AVCS (Advanced Vehicle Control System). In this paper, a lane departure monitoring and control system is developed and evaluated in the hardware-in-the-loop simulations. This system consists of lane sensing, lane departure monitoring and active steering control subsystems. The road image is obtained based on a vision sensor and the lane parameters are estimated using image processing and Kalman Filter technique. The active steering controller for avoiding the lane departure is designed based on the lane departure metric. The proposed lane departure avoidance system is realized in a steering HILS (hardware-in-the-loop simulation) tool and its performance is evaluated with a driver in the loop.     

A Novel Integrated Stability Control Based on Differential Braking and Active Steering for Four-axle Trucks

Di erential braking and active steering have already been integrated to overcome their shortcomings. However, existing research mainly focuses on two-axle vehicles and controllers are mostly designed to use one control method to improve the other. Moreover, many experiments are needed to improve the robustness; therefore, these control methods are underutilized. This paper proposes an integrated control system specially designed for multi-axle vehicles, in which the desired lateral force and yaw moment of vehicles are determined by the sliding mode control algorithm. The output of the sliding mode control is distributed to the suitable wheels based on the abilities and potentials of the two control methods. Moreover, in this method, fewer experiments are needed, and the robustness and simultaneity are both guaranteed. To simplify the optimization system and to improve the computation speed, seven simple optimization subsystems are designed for the determination of control outputs on each wheel. The simulation results show that the proposed controller obviously enhances the stability of multi-axle trucks. The system improves 68% of the safe velocity, and its performance is much better than both di erential braking and active steering. This research proposes an integrated control system that can simultaneously invoke di erential braking and active steering of multi-axle vehicles to fully utilize the abilities and potentials of the two control methods.     

基于单片机技术的导弹火力控制系统设计与实现

通过对现役舰载导弹武器火控系统的深入研究,采用单片机技术实现了导弹火力控制系统,在硬件、软件开发设计中融合了EDA技术、铁电RAM技术等多种新理论新技术,具有较高的效费比.通过多重保密措施处理,确保系统安全可靠地运行,提高了装备的持续战斗性能.