基于ZPETC和DOB的直线电机控制器设计及实验研究

直线电机驱动系统中存在的负载力、推力波动等干扰力会引起跟踪误差,降低跟踪性能。干扰观测器可以检测并补偿干扰,有效提高系统的抗干扰能力。前馈控制是提高系统跟踪性能的另一种方法,如直接速度前馈控制器、零相位误差跟踪控制器等,可以有效提高系统带宽,提高跟踪性能。针对直线电机在抗干扰和动态响应方面的需求,该文研究了基于直接速度前馈控制器、零相位跟踪控制器和干扰观测器的直线电机控制方法,并给出实验结果。结果表明,直接速度前馈控制器使位置能够无静地跟踪二阶指令输入,干扰观测器能够很好的抑制推力波动和摩擦力的影响,零相位跟踪控制器能够提高位置闭环带宽,改善跟踪性能,特别是三阶位置指令输入时的跟踪误差。     

Motion of control of a multijoint robot based on a robust velocity controller

This paper proposes a simple and robust robot motion control method using a robust velocity controller. The robust velocity controller is based on H^∞ control theory, and is called H^∞ velocity controller. The H^∞ velocity controller based motion control method is completely equivalent to the robust acceleration control method using the H^∞ acceleration controller, but it has simpler structure. Therefore, the proposed system can realize a fine robot motion control easily. To confirm the validity of the proposed method, this paper realizes the hybrid control of position and force for a multijoint robot manipulator. Further, the simple realization of hybrid control is proposed considering the attitude of the robot manipulator. This system achieves hybrid control of position and force of the robot manipulator while maintaining a perpendicular attitude to the target environment. The experimental results in this paper show that the proposed system has the desired force and position response to the target environment. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 118 (4): 58–69, 1997     

为提高轮廓加工精度采用DOB和ZPETC的直线伺服鲁棒跟踪控制

为了提高轮廓加工精度,本文针对高精度直线伺服系统,提出了一种将零相位误差跟踪控制器(ZPETC)和干扰观测器(DOB)相结合的鲁棒跟踪控制策略.ZPETC作为前馈跟踪控制器,保证了快速性,使系统实现准确跟踪;基于DOB的鲁棒反馈控制器补偿了外部扰动、未建模动态、系统参数变化和机械非线性等,保证了系统的强鲁棒性能.仿真结果表明了所提出的控制方案是有效的,既能实现完好跟踪,又有较强的鲁棒性能.从而有效地减小了轮廓误差,提高了轮廓加工精度.     

Adaptive motion/force tracking control of holonomic constrained mechanical systems: a unified viewpoint

This paper proposes a robust adaptive motion/force tracking controller for holonomic constrained mechanical systems with parametric uncertainties and disturbances. First, two types of well‐known holonomic systems are reformulated as a unified control model. Based on the unified control model, an adaptive scheme is then developed in the presence of pure parametric uncertainty. The proposed controller guarantees asymptotic motion and force tracking without the need of extra conditions. Next, when considering external disturbances, control gains are designed by solving a linear matrix inequality (LMI) problem to achieve prescribed robust performance criterion. Indeed, arbitrary disturbance/parametric error attenuation with respect to both motion and force errors along with control input penalty are ensured in the L₂‐gain sense. Finally, applications are carried out on a two‐link constrained robot and two planar robots transporting a common object. Numerical simulation results show the expected performances. Copyright © 2006 John Wiley & Sons, Ltd.     

扰动补偿的陀螺稳定平台单神经元自适应PI控制

针对陀螺稳定平台受未知非线性干扰的影响,提出了一种基于扰动补偿的单神经元自适应PI控制策略.利用扰动观测器观测出各种扰动,将其作为补偿信号前馈到控制输入端,提高平台的抗干扰能力;同时利用神经元的自学习和自适应力对PI参数进行在线调整,保证了平台在外界扰动和系统参数变化情况下对目标稳定跟踪的能力.通过在某型号实验装置上的试验结果表明,该方法对不确定扰动具有较强的抗干扰能力,提升了稳定平台的自适应性和鲁棒性.     

双三相永磁同步电机位置伺服前馈反馈复合控制

传统伺服系统的位置控制器只采用纯比例控制,不能兼顾系统的响应速度和稳定裕度,且对斜坡等输入信号不能实现无差跟踪。通过分析位置伺服系统的传递函数,设计了一种新型前馈反馈复合控制器。该复合控制器重构了系统的误差传递函数,使系统能够准确跟踪给定信号,提高了伺服系统的跟踪性能和稳定性。为了进一步提升电流环动态性能,在电流环添加反电动势前馈势补偿,用于减小反电动势对电流响应的影响。仿真和试验表明,该控制方法提高了位置伺服系统的动态性能和跟踪精度,验证了前馈反馈复合控制的有效性。     

永磁直线同步电机自适应反推滑模控制

针对高速高精数控机床直线伺服系统,考虑参数变化、外部负载扰动和摩擦力等不确定因素对系统伺服性能的影响,设计反推滑模控制器(ABSMC).实际应用中不确定确界未知,通过设计自适应率修正不确定确界观测值.经分析验证,并与反推滑模控制相比,自适应反推滑模算法在保证系统全局一致渐进稳定情况下,能很好抑制不确定因素对系统性能的影响,位置跟踪鲁棒性强,同时抖振得到明显削弱.     

曲面轮廓恒力跟踪的非线性双闭环控制

针对机器人在跟踪未知曲面轮廓运动时,由于缺乏位置信息导致的接触力不恒定的问题,提出了非线性双闭环控制方法。该方法中的双闭环包括运动倾角的实时反馈校正器,以及基于非线性PID的法向接触力控制器。非线性PID控制器是由非线性跟踪微分器(TD)和状态误差反馈(SEF)构造的,基于线性PID框架的非线性控制器。首先,根据受力模型得到基于力反馈的运动倾角校正策略;另外,考虑到多维力传感器维间耦合的影响,对Maxwell三维力传感器的解耦矩阵进行了标定;同时,提出了力信号的自适应惯性滤波方法,改善了滤波器的灵敏度和稳定性,综合性能提高了34.42%;最后,实验验证了双闭环控制方法能有效提高力控制精度和稳定性,具有较强的可执行性和适应能力。     

基于模型扰动抑制的直线伺服系统设计

针对高精度、微进给永磁直线交流同步电机 (PMLSM )驱动系统 ,采用基于模型的扰动抑制 (MBDA)方法 ,对诸如摩擦力、切削力、负载变动之类的扰动进行抑制。MBDA是利用一个与系统并行的标称模型 ,通过输出反馈 ,将系统输出与标称模型输出进行比较 ,得出误差信号 ,并通过设计一个补偿器将误差信号反馈给被控对象的输入端 ,从而实现扰动抑制。同时 ,针对速度环设计了积分 -比例 (IP)控制器 ,以满足系统快速跟踪指令的要求 ,并且其具有较强的抗扰动能力。仿真结果表明 ,该控制方法响应速度快 ,抗干扰能力强     

永磁直线同步伺服系统混合递归模糊神经网络控制

针对直线电机易受诸多不确定因素的影响，提出了采用递归模糊神经网络和扰动观测器的控制方案。系统采用IP位置控制器；扰动观测器将所观测的扰动力前馈，提高了系统的抗干扰能力。为改善系统受到突加减扰动时的伺服性能，引进了递归模糊神经网络补偿器，采用动态反馈学习算法，在线调整。仿真结果表明，该控制方案可以有效增强系统的鲁棒性。     

直线伺服系统基于模型扰动抑制的设计

文章针对高精度、微进给永磁直线交流同步电机(PMLSM)驱动系统，采用基于模型的扰动抑制(MBDA)^[1]方法，对诸如摩擦力、切削力、负载变动之类的扰动进行抑制。MBDA是利用一个与系统并行的标称模型，通过输出反馈，将系统输出与标称模型输出进行比较，得出误差信号，井通过设计一个补偿器将误差信号反馈给被控对象的输入端，从而实现扰动抑制。同时，针对速度环设计了积分—比例(IP)控制器，以满足系统快速跟踪指令的要求^[2]，井具有较强的抗扰动能力。仿真结果表明，该控制方法响应速度快，抗干扰能力强，且能有效地提高加工精度。     

System for off‐line feedrate optimization and neural force control in end milling

Based on hybrid process modeling, off‐line optimization and neural control scheme (NCS), the combined system for off‐line optimization and adaptive adjustment of cutting parameters is built. This is an adaptive control system controlling the cutting force by digital adaptation of cutting parameters. In this way, it compensates all disturbances during the cutting process, prevents excessive tool wear, and maintains a high chip removal rate. It is the combination of these methods that yields accurate force control. The basic control principle is based on the NCS consisting of two neural identifiers of the process dynamics and feedback controller. An overall procedure of hybrid modeling of cutting process, used for working out the computer numerical control (CNC) milling simulator has been prepared. CNC simulator is used to evaluate the controller design before conducting experimental tests. Numerous simulations and experiments have been conducted to confirm the efficiency of this control architecture. The experimental results show that not only does the end‐milling system with the design controller have high robustness and global stability, but also the machining efficiency of the end milling system with the proposed controller is 27% higher than for traditional CNC milling system. Copyright © 2011 John Wiley & Sons, Ltd.     

基于ZPETC和DOB的永磁直线同步电机的鲁棒跟踪控制

针对高精度永磁直线同步电机直接驱动伺服系统，提出了一种将零相位误差跟踪控制器(ZPETC)和干扰观测器(DOB)相结合的鲁棒跟踪控制策略，以提高系统的跟踪性能和鲁棒性能。ZPETC作为前馈跟踪控制器，保证了快速性，使系统实现准确跟踪；基于DOB的鲁棒反馈控制器补偿了外部扰动、未建模动态、系统参数变化和机械非线性等，保证了系统的强鲁棒性。仿真结果表明，所提出的控制方案在保证系统实现完好跟踪的同时，又具有较强的鲁棒性，从而改善了数控机床进给系统的定位精度，进而提高了轮廓加工精度。     

Adaptive robust output‐feedback motion control of hydraulic actuators

Most previous advanced motion control of hydraulic actuators used full‐state feedback control techniques. However, in many cases, only position feedback is available, and thus, there are imperious demands for output‐feedback control for hydraulic systems. This paper firstly transforms a hydraulic model into an output feedback–dependent form. Thus, the K‐filter can be employed, which provides exponentially convergent estimates of the unmeasured states. Furthermore, this observer has an extended filter structure so that online parameter adaptation can be utilized. In addition, it is a well‐known fact that any realistic model of a hydraulic system suffers from significant extent of uncertain nonlinearities and parametric uncertainties. This paper constructs an adaptive robust controller with backstepping techniques, which is able to take into account not only the effect of parameter variations coming from various hydraulic parameters but also the effect of hard‐to‐model nonlinearities such as uncompensated friction forces, modeling errors, and external disturbances. Moreover, estimation errors that come from initial state estimates and uncompensated disturbances are dealt with via certain robust feedback at each step of the adaptive robust backstepping design. After that, a detailed stability analysis for the output‐feedback closed‐loop system is scrupulously checked, which shows that all states are bounded and that the controller achieves a guaranteed transient performance and final tracking accuracy in general and asymptotic output tracking in the presence of parametric uncertainties only. Extensive experimental results are obtained for a hydraulic actuator system and verify the high‐performance nature of the proposed output‐feedback control strategy.     

基于扰动观测器的电压源型逆变器控制

基于扰动观测器(DOB)的原理,结合PWM电压源型逆变器受控对象的特点,为逆变器提出了一种新的控制策略,并设计了相应的附加型扰动观测器。将附加型扰动观测器作为补偿器添加到传统的双环反馈控制系统中,提高了逆变器输出的抗干扰性能和动态响应速度。这种附加型扰动观测器结构简单、实现时所需计算量小且不需要增加新的采样信号,适合工程应用。在基于DSP MC56F8323的PWM逆变器系统中对新的控制系统和传统的控制系统进行比较,该附加型扰动观测器的有效性和实用性得到了验证。     

仿人型机器人手的力矩保持功能及控制系统

针对仿人型机器人手的力矩保持问题,利用混合式步进电机的自锁特性,设计了具有力矩保持功能的手指驱动器,使手指抓取物体时保持抓取力不减小,同时电机不消耗电流.采用非线性跟踪微分器对位置信号滤波得到速度信号,设计了位置控制器和阻抗力矩控制器.实验结果证明,基于步进电机的自锁机构具有体积小,噪音低的优越性,阻抗控制器的力矩控制结果较好.     

基于自抗扰的高速列车升力翼攻角驱动系统同步控制

针对高速列车升力翼中双电机协同控制攻角高精度控制的问题,提出了一种基于改进型自抗扰控制器的新型控制策略。该策略改进位置环,并将交叉耦合结构中的位置误差反馈至电流环,实现高精度控制,从而解决高速列车升力翼系统在实际应用中存在的滞后性以及抗干扰能力弱等问题。通过MATLAB/Simulink仿真验证该方法的快速响应能力、抗干扰能力以及电机同步效果。仿真结果表明,在给予不同负载扰动的情况下,该方法能够极大地提升系统的响应速度,且抗干扰能力与同步效果优异,能够帮助高速列车升力翼实现高精度的攻角变换。     

Adaptive fixed-time minimal learning force/position control of uncertain manipulators subject to input saturation

This article solves the fixed-time force/position control problem for constrained manipulators in the presence of input saturation and uncertain dynamics. Under the fixed-time stability theory, a novel fixed-time auxiliary dynamic system (ADS) is first presented to compensate for the effects of input saturation nonlinearity. System uncertainties are estimated by using radial basis function neural networks (RBF NNs) and only need to tune one neural parameter online. In addition, with a fixed-time sliding mode surface and the proposed fixed-time ADS, a novel fixed-time adaptive neural force/position controller is designed which can not only ensure the fixed-time stability of the position tracking error but also enable the manipulator to track the desired force trajectory. By using the Lyapunov method, the boundedness of all signals in the closed-loop system is proved. Finally, the effectiveness of the proposed method is demonstrated by comparative simulation works.     

永磁同步直线电动机的自适应模糊滑模控制

将永磁同步直线电动机应用于驱动精密定位平台时,由于直线电动机存在端部效应引起的推力波动、动子磁链非正弦性、摩擦非线性等都将使精密定位平台伺服系统性能变坏。因此,必须采用鲁棒性强的控制策略来抑制这些扰动。提出了一种针对永磁同步直线电动机的自适应模糊滑模控制算法,具有快速性和稳定性,对参数不确定、参数变化和外部扰动具有不变性。该算法由位移、速度、位移误差和速度误差的积分建立了滑模面,建立特定的自适应律,应用模糊系统逼近滑模控制器的输出,最后应用一个切换控制函数来补偿滑模控制器的输出误差。经仿真结果验证,该控制算法能明显地改善永磁同步直线电动机的位移输出精度和速度跟踪性能,具有较好的快速响应性和鲁棒性。     

永磁同步电机混合LQ—H∞控制研究

为了抑制永磁同步电机存在的参数摄动、负载扰动等不确定因素对系统性能的影响,该文提出了一种将线性二次型（LQ）最优控制同H∞鲁棒控制相结合的鲁棒跟踪控制策略。H∞控制作为抗扰调节器,保证系统的鲁棒性能,克服系统中存在的模型不确定性与外部干扰对系统性能的影响;LQ最优控制作为跟随调节器可以保证系统的跟踪性能。仿真结果表明,设计的LQ—H∞混合控制器对参数摄动和负载扰动具有较强的鲁棒性,而且系统具有较强的跟踪性能。