电磁作动器的设计及磁路分析

针对船舶发动机振动主动控制系统,提出一种高效电磁作动器。基于电磁作动力为目标设计电磁作动器结构,并对电磁作动力进行理论计算。建立电磁作动器磁场模型,给定直流加载对磁场模型进行仿真分析,计算电磁作动力与磁感应强度。在此理论基础上,以直流信号输入对电磁作动器进行试验验证。结果表明,试验与仿真分析得出的电磁作动力达到预定设计目标,最大磁感应强度基本吻合且未达到磁饱和强度,符合设计要求。验证了应用ANSYS对磁场进行仿真研究的准确性,且相同大小体积下电磁作动器输出的作动力大、性能良好,可以较好地应用于发动机的振动主动控制。     

基于工程车辆减振系统的单向电磁作动器结构及控制律设计

阐述了单向电磁作动器的工作原理，结合交流电磁铁的简化模型与电磁机构的设计原理，设计出单向电磁作动器的结构。将振动主动控制应用到工程车辆座椅的减振系统中，建立减振系统的数学模型，将现代控制理论应用于控制器的控制律设计。以振动压路机为模型，应用Matlab软件对闭环系统进行了振动响应仿真，结果表明单向电磁作动器能够有效地减小工程车辆的振动响应。     

微重力主动隔振系统电磁作动器设计与仿真

为满足空间科学实验载荷对微重力环境的要求,需应用隔振系统对实验载荷进行振动抑制。由于被动隔振仅在特定频率范围有效,低频振动抑制必须采用主动隔振手段。在主动隔振的若干种作动器中,电磁作动器以电气传动、非接触、响应速度快和允许偏移大等特点适用于微重力主动隔振系统。本文设计了一种基于洛伦兹力原理的电磁作动器,并利用有限元软件ANSYS Workbench对作动器特性进行仿真,了解作用力与电流和位移的关系。     

比例电磁式主动吸振器的设计方法研究

以电磁铁为作动器,开展了电磁式主动吸振器设计方法的研究。对主动吸振器电磁作动器进行了设计研究,针对基于E型电磁作动器的主动吸振器具有非对称驱动力的问题,设计了一种具有盘形磁极面的比例电磁作动器。采用有限元和试验验证的方法,对电磁作动器在不同磁极面结构参数组合下的电磁力进行了正交仿真计算和验证,以在一定的动铁心位移范围内电磁力波动最小为目标,获得了最优组合的磁极面结构参数。对主动吸振器动质量的动态位移进行了计算分析,并基于主动吸振器的工作频带和目标驱动力,设计了动铁心的静平衡位置。计算了主动吸振器设计刚度值,并分析了刚度参数对吸振器电磁力特性的影响。最后,结合理论计算和试验验证的方法,分析了比例电磁式主动吸振器近似对称的驱动力特性。     

汽车发动机主动悬置模糊控制研究

压电陶瓷作动器作为一种主动作动器,运用到发动机悬置中具有重要的意义。从压电陶瓷作动器力学模型出发,运用实验对其特性进行了研究。同时建立了发动机五自由度主动悬置模型以及路面谱模型;分别设计了基于压电陶瓷主动悬置系统的模糊控制器和SIRMs模糊控制器,并利用Matlab/Simulink软件进行仿真研究。结果表明SIRMs模糊控制相对于传统模糊控制和被动悬置可以有效的减小发动机质心加速度,车身质心加速度以及悬置动行程,同时明显提高了汽车的乘坐舒适性。     

基于磁控形状记忆合金主动减振系统自适应控制

对磁控形状记忆合金(MSMA)应用于主动减振系统进行研究,通过仿真试验,研究自适应控制算法进行振动主动控制的效果。基于FIR数字滤波器,采用Fx-LMS自适应控制算法对基于MSMA作动器的主动减振系统的控制算法进行推导,对单自由度振动系统主动减振进行Simulink仿真。结果表明,Fx-LMS自适应控制算法具有良好的控制性能,利用MSMA作动器进行主动减振控制具有快速减小振动的效果,能有效降低振动对设备带来的不利影响,提高设备的使用寿命。     

轴向运动弦线横向振动控制的自适应方法

对轴向运动弦线和作动器组成的耦合系统的横向振动控制进行研究。此系统被作动器分成未控和受控两部分,通过作用在作动器上的控制力对受控部分进行主动控制。分析未控弦线的横向振动的有界性。采用Lyapunov 方法获得自适应控制规律,并证实受控弦线横向振动的渐近稳定性。在初始扰动和激励力作用下,通过数值仿真证实控制规律的有效性。     

BTA深孔钻杆振动主动控制实验研究

为减小BTA深孔钻削加工过程中钻杆振动对刀具寿命和工件加工精度的影响,开发了一种钻杆振动主动控制系统。所设计的超磁致作动器(GMA)能够满足钻削振动高频响和高精度的控制要求。在系统总体设计的基础上分别对钻杆振动模型和作动器动力学特性进行了分析,建立了传递函数模型。利用MATLAB软件对PID算法控制系统进行仿真,最终通过实验验证了所设计的振动主动控制系统对钻杆振动抑制的有效性。     

基于功率流法双层隔振系统振动传递

针对双层隔振系统,划分子结构系统,建立子系统传递矩阵,采用平均振动能量作为目标函数,利用功率流法合成系统传递关系,实现被动隔振过程振动传递特性研究.在上层隔振器和中间质量之间加入作动器,通过二次型目标函数最优,实现主被动隔振过程振动传递特性研究.根据双层隔振系统实际参数进行数值仿真和试验研究,获取多传递通道系统振动分布,并实现系统振动传递特性研究.数值仿真和试验研究结果表明,系统主导模态、耦合和阻尼等耗散特征以及初级激扰力特征决定多振动通道振动能量的分布和传递特性.     

电动静液压主动悬架的内模-Smith时滞补偿控制

提出一种内模-Smith时滞补偿控制方法进行电动静液压主动悬架的时滞控制。对电动静液压作动器(Electro-Hydrostatic Actuator,EHA)进行了响应特性试验,采用一维线性插值方法对试验数据进行了模型拟合,并得到了含纯时滞的作动器简化模型。针对作动器的惯性响应设计了内模控制器,利用一阶泰勒表达式转化成了PID控制器形式;将作动器的纯时滞视为理想主动力的时滞,设计了Smith时滞补偿控制器。搭建了EHA主动悬架的内模-Smith时滞补偿控制仿真模型,并进行了仿真分析。结果表明,内模-Smith时滞补偿控制能使作动器输出的主动力在时间上得到较好的控制,明显改善了主动悬架的动态性能。     

Effectiveness of a passive-active vibration isolation system with actuator constraints

In the prediction of active vibration isolation performance, control force requirements were ignored in previous work. This may limit the realization of theoretically predicted isolation performance if control force of large magnitude cannot be supplied by actuators.The behavior of a feed-forward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions comprising a combination of the vibration transmission energy and the sum of the squared control forces are proposed. The example system considered is a rigid body connected to a simply supported plate via two passive-active isolation mounts. Vertical and transverse forces as well as a rotational moment are applied at the rigid body, and resonances excited in elastic mounts and the supporting plate are analyzed. The overall isolation performance is evaluated by numerical simulation. The simulation results are then compared with those obtained using unconstrained control strategies. In addition, the effects of waves in elastic mounts are analyzed. It is shown that the control strategies which rely on tmconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. In the frequency range in which rigid body modes are present, the control strategies can only achieve 5-10 dB power transmission reduction, when control forces are constrained to be the same order of the magnitude as the primary vertical force. The resonances of the elastic mounts result in a notable increase of power transmission in high frequency range and cannot be attenuated by active control. The investigation provides a guideline for design and evaluation of active vibration isolation systems.     

A novel design of active accelerator pedal using linear electromagnetic actuator

This paper describes a novel design of an active accelerator pedal(AAP) using a linear electromagnetic actuator that transfers warning messages recognized by the automobile from the sensors to the driver. In an emergency driving situation, the electromagnetic actuator creates additional pedal forces such as active pedal force and vibration force. In a passive situation however, the actuator does not produce additional force. In the past, a system with a rotary actuator was developed for AAP but was found to have critical drawbacks such as inaccurate movement by backlash and torque occurrence due to the high gear ratio. This research, therefore, aims to solve these drawbacks and maximize car safety by optimizing the electromagnetic linear actuator. Finite element analysis is performed to analyze the coupled system of electric, magnetic, and mechanical subsystems, and to characterize the dynamic performance of the proposed actuator system. A novel design of the AAP system with the optimized electromagnetic linear actuator is developed. The dynamic characteristics of the AAP system are simulated by a 3D dynamic analysis software program. Satisfactory results were obtained. Finally, the test result and the simulation result of the AAP system are compared.     

双层主动隔振系统的动力学研究

研究了在消极隔振情况下，双层主动隔振系统在其主动隔振执行器的3种不同安装方式的动力学特性，分析了主动控制力与被动隔振器参数之间的关系。研究结果表明，对于双层主动隔振系统，隔离中低频振动时，主动隔振执行器安装于中间质量与基础之间的隔振性能最好，安装于隔振对象与中间质量之间的隔振性能最差；隔离高频振动时，主动隔振执行器安装于隔振对象与中间质量之间或仅作用于隔振对象时的隔振性能均较好，但主动隔振执行器安装于中间质量与基础之间所需的主动隔振控制力也不大。     

负载口独立控制系统主被动加载试验台振动特性分析

主被动加载试验台是对负载口独立控制系统进行主动和被动控制性能试验测试的关键设备。为了分析试验台加载过程中加载力对试验台的振动特性的影响,采用有限元网格划分软件Hypermesh对试验台整机进行了网格划分,定义了材料属性,并通过有限元仿真软件ANSYS Workbench对主被动加载试验台分别进行了静力学分析、模态分析、位移谐响应分析和加速度谐响应分析。仿真结果表明:从试验台的振动过程中的固有频率变化、振幅变化、位移响应分布、加速度响应分布、振动传动路径等可知,主被动试验台在加载试验中,将加载力的频率控制在35 Hz以内,可以避免由于加载而产生的试验台共振现象。     

车辆液压主动悬架系统的设计与性能研究

基于混合控制策略,提出了一种液压主动悬架作动器;对混合控制策略进行理论分析,并建立混合控制策略和液压作动器的传递函数,分析液压系统控制力的实现过程;依据1/4车辆模型选取和设计液压元件;在AMESim软件中对液压系统的减振性能进行分析,并对液压主动作动器进行试制与试验。仿真与试验结果均证明设计的液压系统合理,能够满足主动减振的要求,为国内自主研发液压主动悬架提供了一定的参考价值。     

超精密隔振平台主动振动控制系统设计

建立了超精密隔振平台的结构及动力学模型，设计了一种新型的双向电磁作动器，并采用PID控制算法建立了主动振动控制系统模型，经Matlab软件仿真分析表明，该系统具有良好的隔振效果。     

DESIGN AND ANALYSIS OF NOVEL ACTIVE ACTUATOR TO CONTROL LOW FREQUENCY VIBRATIONS OF SHAFT SYSTEM

Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.     

卧式车床车削振动主动控制系统设计与实验研究

分析了车削加工时振动的一般模型,并根据不同车削振动来源建立了它们各自的振动力与振动位移关系模型.针对机床运动失衡下的周期性振动,提出了一种振动主动控制方法.设计了基于PID控制算法与超磁致执行器的车削振动主动控制系统.通过数字仿真与现场试验,表明所设计的车削振动主动控制系统能有效地降低车削振动,提高车削加工精度.     

Reducing the seat vibration of vehicle by semi active force control technique

This article focusses on reducing the axis acceleration and minimizing the vertical displacement by using an air spring actuator and active force control as a main control element. In active force control loop track the developed force of an air spring actuator is fed as a feedback to the actuator. Mamdani and sugeno type fuzzy interference system are used to develop a desired force and to estimate mass of the system respectively. The performance of the system is analyzed for both time and frequency domains and contrasted with passive suspension due to the irregular road disturbances. While developing the simulation model, quarter car suspension with seat as three degree of freedom and an air spring actuator acting as a force generator are modeled as non-linear system. The simulation result shows the effectiveness of the proposed control scheme in suppressing the undesirable effects of the suspension system.     

Vehicle active suspension system using skyhook adaptive neuro active force control

This paper aims to highlight the practical viability of a new and novel hybrid control technique applied to a vehicle active suspension system of a quarter car model using skyhook and adaptive neuro active force control (SANAFC). The overall control system essentially comprises four feedback control loops, namely the innermost proportional-integral (PI) control loop for the force tracking of the pneumatic actuator, the intermediate skyhook and active force control (AFC) control loops for the compensation of the disturbances and the outermost proportional–integral–derivative (PID) control loop for the computation of the optimum target/commanded force. A neural network (NN) with a modified adaptive Levenberg–Marquardt learning algorithm was used to approximate the estimated mass and inverse dynamics of the pneumatic actuator in the AFC loop. A number of experiments were carried out on a physical test rig using a hardware-in-the-loop configuration that fully incorporates the theoretical elements. The performance of the proposed control method was evaluated and compared to examine the effectiveness of the system in suppressing the vibration effect on the suspension system. It was found that the simulation and experimental results were in good agreement, particularly for the sprung mass displacement and acceleration behaviours in which the proposed SANAFC scheme is found to outperform the PID and passive counterparts.