基于二次型性能泛函的主动控制致动器优化配置

致动器过多不仅增加控制能量和成本,而且会增加控制难度及降低控制效率。已有的优化配置研究中,已对一定数目致动器的位置配置进行了探讨,而对致动器的最优数目研究较少。本文首先根据致动器对结构系统的状态影响矩阵中控制贡献大小,提出控制系统中致动器最优数目的优化方法;然后根据致动器的灵敏度,提出改进的最优致动器布置计算方法及算法流程,提高计算效率,并通过实例进行了验证,说明本文提出改进的致动器优化配置算法流程的适应性和有效性,更能适应于大型土木工程结构主动控制中的致动器优化配置。     

Magnetic field of mathematical modeling and simulation of 3D magnetic pole array spherical actuator

In this paper a new spherical actuator is designed and its advantages are compared to an existing spherical actuator,which function is limited by several design bottlenecks. First the output torque is too small.Second,the attitude is difficult to be accurately detected. The new three-dimensional magnetic pole array can solve these major problems. The new actuator features an outer rotor with multiple permanent magnet( PM)poles. Using an analytical solution and the finite element solution simulation,the feasibility of the approach is verified. A prototype was developed,tested,and experiments were conducted to obtain the practical value of the magnetic flux density.     

压电执行器在螺纹插装阀中的应用研究

论文探讨了将压电晶体(PZT)执行器应用于液压螺纹插装阀上的可能性.介绍了常用的智能执行器,并进行性能比较,选择压电晶体作为螺纹插装阀的执行器.提出利用PZT阀作为先导阀控制主阀的新方法.建立液压回路数学模型并进行仿真分析;建立实验测试系统,并进行性能测试.实验结果表明,PZT阀能够成功地控制主阀的油液切换,实验结果与仿真研究吻合得很好;同时提出了一种提高主阀响应速度的改进措施.     

A control model for hysteresis based on microscopic polarization mechanisms in piezoelectric actuator

Aiming at the limitation of control accuracy caused by hysteresis and creep for a piezoelectric actuator, the hysteresis phenomenon is explained based on the microscopic polarization mechanism and domain wall theory. Then a control model based on polarization is established, which can reduce the hysteresis and creep remarkablely. The experimental results show that the polarization control method is with more linearity and less hysteresis compared with the voltage control method.     

一种大量程表面轮廓综合测量仪

为了解决传统位移传感器大量程与高精度不可兼得的问题,研制了一种表面轮廓综合测量仪.该仪器采用二维位移传感器和垂直扫描工作台.压电陶瓷驱动器和伺服电机根据零位偏移量驱动垂直扫描工作台进行垂直方向的位移,确保测量杠杆总是在每个采样间隔回到平衡位置,即使在量程增大的情况下由杠杆旋转引起的非线性测量误差也非常小.由实验和理论分析可知,该仪器可对球面、台阶、沟槽和其他各种曲面的表面粗糙度和轮廓尺寸进行精确测量.     

电液执行机构的应用及维护

文中以某石化公司使用的LBHF电液执行机构为例,介绍了特阀电液执行机构的工作原理与主要结构以及在重油催化装置上的应用。并结合实际情况,对近几次二再双动滑阀发生的故障进行分析,总结了电液执行机构常见故障的判断和处理方法。同时对特阀及其电液执行机构的安全生产提出了一些建议。     

基于CAN总线的船舶阀门遥控系统

利用一种新型的智能电液阀门驱动装置、工业控制计算机,结合CAN总线技术,从软、硬件两方面设计了船舶阀门遥控系统,实现了对船上各个阀门的远程控制及对其状态的实时显示。该方案的实现可以提高船舶机舱自动化水平。     

压电陶瓷驱动器性能的理论计算与ANSYS仿真

通过理论推导与ANSYS仿真的方法对普通平面电极型压电驱动器及交叉指形电极型压电驱动器的自由应变进行分析,得到x和y方向的自由应变,并与N.Hagood等人的实验结果进行对比。结果表明：ANSYS仿真结果与理论计算结果非常接近,x方向自由应变误差仅为0.35%和-14%;采用应变片直接测量驱动元件局部表面的应变有较高的误差,x方向应变误差分别为147%和73.3%;交叉指形电极的压电驱动元件表现出较高的正交各向异性,横向效应系数是普通平面电极压电驱动器的2.2倍。     

FTC approach with actuator saturation avoidance based on reference management

In this paper, a fault recovery approach using dynamic reference modification and reconfigurable linear quadratic regulator is proposed. The idea is to modify the reference according to the system constraints, which become more strict after fault occurrence to avoid any actuator saturation and ensure system stability. The effectiveness of the proposed method is evaluated by a performance index based on tracking reference error and illustrated by an aircraft example subject to actuator faults and constrained on the actuator dynamic ranges. Copyright © 2013 John Wiley & Sons, Ltd.