一种可有效克服系统滞环特性影响的控制方法及试验研究

本文提出了一种可有效消除控制系统滞环特性影响的控制方法，即环外输入信号幅值调整法。在人工关节试验机力伺服控制系统中使用本方法后，控制效果明显。     

用FCGA优化的四辊冷轧机恒张力模糊控制系统

为了保证冷轧机轧制中带钢恒张这一特点，设计了四辊冷轧机恒张力模糊控制系统。该系统含有电压、电流和速度三个内环，最外环为张力环；电压环和电流环采用一维模糊控制器控制，速度环和张力环采用二维模糊控制器控制。为了加强模糊控制的自适应性，采用了一种模糊控制的遗传算法将外张力模糊控制器的隶属参数进行优化。理论分析和仿真结果都表明该系统对带钢恒张控制具有很强的鲁棒性和实时性，即使在变工况下（大范围变负荷下）也保持了良好的控制性能。     

永磁同步电机的二阶自抗扰控制仿真

在永磁同步电机的控制中往往使用矢量控制系统,其包括电流环、转速环和位置环等3种反馈调节。传统控制方案为PID控制,通过调节其参数改善控制效果。但当扰动存在且比较大时,PID的控制效果往往不佳。在系统中使用二阶自抗扰(Sencond-order Active Disturbance Rejection Controller,ADRC)控制器代替转速环反馈。永磁同步电机矢量控制系统的二阶ADRC控制器可以提高系统鲁棒性,仿真结果同样支持这一结论。     

电动助力转向系统双闭环模糊PID控制系统分析

电动助力转向系统(EPS)是机电结合的控制系统,电流PID控制是以目标电流和反馈电流为差值的闭环控制系统,模糊控制是以机械转向轴取差值的机电闭环控制系统,本文以力矩反馈环为外环,电流反馈环为内环,设计了一个双闭环控制系统.将模糊PD控制的输出作为助力目标值,然后进行电流PID控制,快速跟踪目标力矩. 经仿真模拟,双闭环模糊PID控制使电动助力转向系统具有更好的跟踪性和稳定性.     

全闭环CNC螺纹磨床主控方式及其原理

ＲＧ２０００ＣＮＣ螺纹磨床的控制系统由全闭环的主控系统及辅助砂轮修形控制系统组成，为多ＣＰＵ多总线控制结果。机床的加工精度不取决于母丝杠精度，而主要取决于位置环和控制系统的综合精度，因此具有很高的加工精度。     

基于DSP的无刷直流电机伺服控制系统设计

以某可调推力固体直接侧向力发动机四轴控制系统为研究背景,设计了一种基于数字信号处理器(DSP)的多通道无刷直流电机位置伺服控制系统.简述了伺服控制系统的软件流程和控制策略,详细介绍了以DSP为核心的主控模块、驱动模块、D/A模块和无刷直流电机及其检测模块等构成的硬件方案,控制策略采用位置环、速度环和电流环构成的三闭环控...     

基于积分分离PID的经纬仪轴系复合控制系统

轴系高精度驱动是实现电子经纬仪目标自动照准的关键技术,轴系电动机直流伺服系统的设计则是其重要环节.根据多回路伺服原理和校正设计方法,建立了经纬仪轴系电动机多回路复合控制系统的数学模型.其中,三闭环控制结构包括电流环、速度环和位置环,位置环采用积分分离PID控制方法,使系统的阶跃响应超调量仅为0.4％.同时,在三闭环结构基础上又引入了前馈反馈和负载力矩干扰补偿,构成了复合控制系统.Simulink仿真结果表明,提出的方法使该系统具备良好的响应速度和控制精度.     

高速率泥浆脉冲器驱动电机控制策略研究

井下随钻系统脉冲器工作条件复杂,同时泥浆泵冲会对电机的控制产生扰动,导致电机的负载特性不同于常规的伺服控制系统。基于永磁同步电机的理论模型和矢量控制理论,建立位置环、速度环和电流环三闭环的控制方法。室内泥浆循环系统的实验结果证明,采用三闭环伺服控制方法,永磁同步电机能够快速准确地跟随正弦位置信号,且具有很好的抗负载扰动能力。     

环锻压机对中装置液压系统设计及分析

环锻压机对中装置性能的好坏直接决定了环形锻件的最终成型质量,文章首先介绍了对中装置机械结构和控制精度要求,其次根据水平对中机构控制精度要求,提出了比例阀控制液压系统、分流集流阀控制系统和同步缸控制液压系统三种控制方式,并对三种控制方式的控制性能展开分析;最后根据竖直举升机构控制精度要求,提出了双泵控制液压系统、分流集流阀控制系统和同步缸控制液压系统三种控制方式,并对双泵控制液压系统的控制性能展开分析。文章提出了多种液压系统控制方式,可根据实际使用需求进行选择。     

大功率风电系统的小波包诊断及优化控制

构建了以鼠笼式感应电机为发电系统的大功率定速变桨距风力发电系统,实现了空气动力学子系统、机械传动链子系统建模;小波变换具有很好的时频特性,而小波包分解更为精细,提出通过小波包分解与重构,进行了高压电机轴承故障诊断的方法;以MATLAB/Simulink为仿真研究工具,实现了各个子系统模块的设计,构建了鼠笼式感应发电机矢量控制系统,设计了转矩控制环、速度控制环和功率控制环的三闭环控制器,并完成了风力发电系统优化控制系统集成,仿真结果表明,该系统能实现大功率风能转换系统的最优控制特性跟踪,能有效解决已装机笼型感应风力发电系统的优化控制和系统改造.     

Dynamic behavior of amplitude detection Kelvin force microscopy in ultrahigh vacuum

The acquisition rate of all scanning probe imaging techniques with feedback control is limited by the dynamic response of the control loops. Performance criteria are the control loop bandwidth and the output signal noise power spectral density. Depending on the acceptable noise level, it may be necessary to reduce the sampling frequency below the bandwidth of the control loop. In this work, the frequency response of a vacuum Kelvin force microscope with amplitude detection (AM-KFM) using a digital signal processing (DSP) controller is characterized and optimized. Then, the main noise source and its impact on the output signal is identified. A discussion follows on how the system design can be optimized with respect to output noise. Furthermore, the interaction between Kelvin and distance control loop is studied, confirming the beneficial effect of KFM on topography artefact reduction in the frequency domain. The experimental procedure described here can be generalized to other systems and allows to locate the performance limitations.     

基于FPGA的科氏质量流量计数字闭环系统设计

设计一种科氏质量流量计(Coriolis mass flowmeter,CMF)数字闭环系统,实现CMF稳定闭环工作条件.采用高速数字电路以及现代信号处理技术取代了传统的模拟正反馈系统来实现CMF闭环控制,使CMF测量管稳定维持在简谐振荡状态.利用模拟数字转换电路(A/D)将传感器输出的信号完整采样,借助现场可编程器件(FPGA,Field Programmable Gate Array)对信号进行分析与处理,根据信号特性进行相应的数字滤波、幅值解算,实现CMF闭环系统的幅值增益和相位的精确控制.实验结果表明:该数字闭环系统具有动态特性好、稳定性好等优点.     

A double-loop structure in the adaptive generalized predictive control algorithm for control of robot end-point contact force

Robot force control is an essential issue in robotic intelligence. There is much high uncertainty when robot end-effector contacts with the environment. Because of the environment stiffness effects on the system of the robot end-effector contact with environment, the adaptive generalized predictive control algorithm based on quantitative feedback theory is designed for robot end-point contact force system. The controller of the internal loop is designed on the foundation of QFT to control the uncertainty of the system. An adaptive GPC algorithm is used to design external loop controller to improve the performance and the robustness of the system. Two closed loops used in the design approach realize the system?s performance and improve the robustness. The simulation results show that the algorithm of the robot end-effector contacting force control system is effective.     

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.     

基于DSP的AOD炉氧枪直线电机伺服控制系统

在对AOD炉氧枪直线电机伺服控制系统数学模型进行研究的基础上,针对直线电机位置伺服控制系统要求有较好的位置跟踪性能的特点,提出了基于对象模型的位置前馈跟踪控制策略。研制出了基于数字信号处理器DSP的直线电机位置伺服控制系统,即位置环为数字控制,由DSP完成,用于实现位置前馈跟踪控制算法和较高的位置控制精度。实验结果:仿真曲线和实验曲线基本吻合。     

A novel dual closed-loop control scheme based on repetitive control for grid-connected inverters with an LCL filter

Grid-connected inverters with LCL filters need high steady-state control accuracy, fast dynamic response performance, and strong robustness to guarantee the power quality. However, there are many problems in traditional control strategies that restrict improvements to control system performance, such as poor dynamic performance of traditional single-repetitive control, large ripples, low steady-state accuracy of inverter current feedback based repetitive dual-loop control or grid-current feedback based single-loop proportional-integral control. In this paper, a novel dual closed-loop repetitive control strategy based on grid current feedback is proposed for single-phase grid-connected inverters with LCL filters. The proportional-integral inner loop is stabilized by using an inherent one-beat delay achieved by digital controller. Based on the inner loop system, a detailed design scheme of a repetitive controller is presented, through which direct control of the grid current is realized, the reference is tracked perfectly to a zero phase shift, and high-attenuation gain is achieved in the high frequency range. In particular, the gird-voltage feed forward control and current reference feedforward control are adopted to suppress grid-voltage disturbance and increase dynamic tracking performance. Finally, the simulation and experimental results show that the proposed method has the advantages of high steady-state accuracy, fast dynamic response, and anti-disturbance ability.     

反馈回路系统诊断策略优化技术研究

针对复杂反馈回路系统的故障诊断问题,提出了一种诊断策略自适应优化生成方法.首先对已有的回路搜索算法进行改进,提出了一种可以快速搜索系统全部反馈回路的算法,然后针对不同情形提出了3种中断回路的策略,在此基础上,提出了诊断策略优化生成算法.该算法以信息增益作为测试排序的启发函数,通过迭代计算得到近似最优的诊断策略.最后给出了主要步骤,并通过实例进行了验证.计算结果表明,该方法可以有效解决复杂反馈回路系统的故障诊断问题.     

Modeling and control of non-square MIMO system using relay feedback

This paper proposes a systematic approach for the modeling and control of non-square MIMO systems in time domain using relay feedback. Conventionally, modeling, selection of the control configuration and controller design of non-square MIMO systems are performed using input/output information of direct loop, while the output of undesired responses that bears valuable information on interaction among the loops are not considered. However, in this paper, the undesired response obtained from relay feedback test is also taken into consideration to extract the information about the interaction between the loops. The studies are performed on an Air Path Scheme of Turbocharged Diesel Engine (APSTDE) model, which is a typical non-square MIMO system, with input and output variables being 3 and 2 respectively. From the relay test response, the generalized analytical expressions are derived and these analytical expressions are used to estimate unknown system parameters and also to evaluate interaction measures. The interaction is analyzed by using Block Relative Gain (BRG) method. The model thus identified is later used to design appropriate controller to carry out closed loop studies. Closed loop simulation studies were performed for both servo and regulatory operations. Integral of Squared Error (ISE) performance criterion is employed to quantitatively evaluate performance of the proposed scheme. The usefulness of the proposed method is demonstrated on a lab-scale Two-Tank Cylindrical Interacting System (TTCIS), which is configured as a non-square system.     

电液步进油缸特性的理论分析及试验研究

针对在高炉和连铸机等重工业恶劣工况下,采用传统液压伺服系统,抗油液污染能力低、可靠性差等问题,依据直接位移反馈闭环控制原理,结合数字化控制方式,开发了步进式电液控制液压缸。阐述了电液步进缸的工作机理,并对其进行数学建模和理论分析,建立了系统传递函数方框图。在试验台上对电液步进缸的内泄漏流量、十脉冲精度、一步精度、重复位置精度和频率响应等静动态性能进行测试,结果表明,电液步进缸在开环状态下也具有较高的控制精度和响应速度,可靠性高、抗油液污染能力强。     

航空光电成像消旋电视数字控制器

介绍了消旋电视摄像系统的工作原理,通过对系统的分析,得出了消旋系统保证像质所允许的最大旋转角速度。根据消旋速度要求,设计了消旋系统的电视数字控制器。该控制器以DSP为核心微处理器;以测速机为速度敏感元件,作为系统速度环的反馈;速率陀螺测得飞行器的扰动速率,用作速度环的前馈。系统采用了传统的超前滞后补偿方法,并加入了积分环节以减小稳态时的漂移角速度。实验结果表明,在消旋拍摄过程中,消旋速度满足设计要求,拍摄图片清晰,消旋速率精度为14.3(°)/s。理论分析和实验结果都证明了该消旋摄像系统的可行性。