网络化现场控制器的设计

一种具有网络功能的嵌入式现场控制器,其主机以高性能ARM9芯片S3C2440作为中央处理器,增强型高速单片机作为采集板控制器,采用RS422总线实现控制器主机和采集板的C/S结构.控制器主机的软件以嵌入式Linux操作系统为平台,采用嵌入式GUI开发系统miniStudio进行开发.该控制器能够采集、显示、存储工业现场常见信号,并能通过Ethernet对控制器实现远程访问.     

基于Linux的嵌入式间歇染色机控制器研究

针对传统间歇式染色机控制器的人机界面不友好、控制功能单一、联网功能不足等缺点,提出了基于嵌入式技术的染色机控制器方案.该方案以嵌入式Linux作为控制器的操作系统,选用ARM芯片作为组合式控制器的CPU,并根据控制柜要求设计了外围电路,采用QT设计了控制器界面并实现了触摸屏显示.现场运行结果表明,该控制器在人机界面、控...     

基于EZ—USB芯片的通用USB控制器硬件设计方法

以Cypress公司的EZ-USB FX芯片为核心芯片,采用USB总线作为外设接口,开发了一个体积小,通用性强,扩展能力好的USB控制器.该控制器可以作为以PC工控机为核心的工控设备的手持控制器模块.     

机械臂神经网络控制优化与仿真

为了提高机械臂末端连杆运动轨迹控制的稳定性,在径向基函数(RBF)神经网络控制器的基础上,采用混合算法优化RBF神经网络控制器.用两个径向基神经网络单元作为自适应控制器,其中一个作为输入端的控制器,另一个作为机械臂的辨识器.将混合算法优化应用到这两个神经网络单元中,以改善网络结构参数对神经网络控制和辨识性能的影响,在Matlab环境下进行了仿真实验,并与RBF神经网络控制器跟踪效果进行对比.仿真结果显示:在受到不确定因素干扰时,机械臂末端连杆采用改进RBF神经网络控制器产生的误差较小,系统反应速度较快,转矩波动较小.机械臂末端连杆采用改进RBF神经网络控制器,具有抗干扰的能力,快速保持系统输出的稳定性.     

浅谈可编程控制器的特点及发展趋势

简单阐述了工业可编程控制器的定义、特点和发展趋势.可编程控制器作为控制系统的三大技术支柱之一,已成为大多数自动化系统的设备基础.     

热轧立辊电液伺服系统的自适应模糊控制

以热轧立辊为研究背景,针对其液压伺服系统存在的非线性、参数不确定性以及负载干扰等特点,基于模糊基函数网络提出一种自适应控制方法.首先将非线性系统线性化并将其作为已知系统,利用这部分已知的动态特性设计反馈控制使标称系统稳定.然后利用模糊基函数网络仅学习非线性系统不确定性的上界,将输出作为补偿控制器的参数,并在Lyapunov稳定意义下构造自适应控制器,该自适应控制器不仅确保了闭环系统的鲁棒性而且加快了跟踪误差的收敛速度.将该控制器应用于某热轧立辊电液位置伺服系统中进行仿真研究,结果表明,该控制器优于传统的PID控制器,可以取得较好的控制效果.     

一种基于PLC的单轴运动控制器

介绍了一种用PLC作为控制单元的单轴控制器.这种单轴控制器具有成本低、控制灵活、开发简单的特点,特别适用于自动生产线.     

PLC在卷烟厂加香工序的应用

在卷烟厂的制丝生产线上,应用PLC作为工序控制器完成系统的高度自动化.系统采用S7-300 PLC作为控制器,控制系统采用PID调节,触摸屏作为人机界面,并采用高精度的流量计,由气动比例调解阀和相应的电气转换器组成执行机构,系统可靠性高,数据准确可靠,使用简单明了.     

基于CAN总线的车身点焊监控系统设计

介绍了一种具有CAN总线通信功能的汽车车身点焊控制器.系统采用CAN现场总线作为通信传输方式组建了监控网络,设计以AT89C51单片机和CAN总线控制器为核心的通信模块,使点焊控制器具有通信功能.设计了底层电阻焊网络控制器的通信控制程序,通信软件和上层管理软件,实现了下位机与上位机之间数据的实时传输.该控制器通信速度快,工作稳定,可应用于汽车车身点焊车间的网络化管理.     

基于Turbo PMAC通用开关检测平台复合PID控制研究

阐述了Turbo PMAC开放式伺服控制结构及其复合PID控制器的工作原理,并将此控制器作为通用开关检测平台的控制系统.分析了控制器中反馈与前馈参数对系统稳态和动态性能的影响.最后通过对这些参数的整定,较好地补偿系统的跟随误差,从而提高系统的性能.     

一类切换模糊PID控制器设计及其仿真

提出了一类高动态性能切换模糊PID控制器设计方法.通过对传统PID控制中比例控制和微分控制作用的分析,结合模糊PID控制器鲁棒性能和自适应性好的优点,设计了一类新的模糊控制器.由于该类控制器先后经历比例控制,微分控制和模糊PID控制的切换,使被控系统不仅具有一般模糊PID控制器的所具有的良好的鲁棒性能和自适应性,而且与一般模糊控制器相比具有更小的超调量和调节时间,是一类动态性能良好的控制器.最后将该控制器应用于一伺服系统进行仿真对比,并给出了Simulink仿真框图.仿真结果说明了该控制器的优越性.     

一种模糊PID控制器在BLDCM系统中的应用

直流无刷电机(Brushless Direct Current Motor,BLDCM)控制是电机控制中的重要问题之一,将一种模糊PID控制器用于直流无刷电机BLDCM控制,PD型模糊控制器的输出信号作为模糊PID控制器积分环节的输入信号,利用模糊PID控制器能够自适应地调节PID控制参数的性能,实现对BLDCM控制系统运行控制。仿真实验结果表明,与一般PID控制器相比,模糊PID控制器控制下的BLDCM电磁转矩输出脉动幅值较小,转矩信号变化稳定,系统输出电流波动频率降低。     

基于自适应滑模控制器的机械臂运动控制方法

由于无法消除机械臂运动过程中存在的高频振动,导致运动控制方法存在跟踪精度低、控制稳定性差和控制性能差等问题。对此,提出一种基于自适应滑膜控制器的机械臂运动控制方法,在机械臂动力学模型的基础上设计非线性观测器,对机械臂控制系统中存在的干扰信号进行观测,设计自适应滑膜控制器对干扰信号进行补偿。将补偿器引入自适应滑膜控制器中,其主要作用是抑制机械臂在运动过程中存在的高频振动,以提高控制稳定性,通过 Lyapunov 函数设计自适应滑膜控制器的总控制律,根据总控制律利用改进后的自适应滑膜控制器完成机械臂的运动控制。实验结果表明,所提方法的跟踪精度高、稳定性好、控制性能高。     

Real-time flow control using neural networks

In this paper, an on-line trained neural network controller is applied to control the flow rate of a process control rig. The neural controller replaces a conventional controller in the forward path. The overall performance of this controller is compared with that of a PID controller in the presence of noise and non-linearity. It is shown that as the non-linearity is added to the system, the PID controller cannot track the set-point changes, however, the neural controller copes well under various conditions.     

基于ADuC812单片机和CAN总线的液压挖掘机泵控系统实现

在挖掘机实验平台上使用单片机ADuC812和工控机PC104,通过CAN总线连接,在PC104E和ADuC812之间进行数据的通信,从而构建了一个分布式控制系统。在该系统上采取一些现代控制算法,使泵的排量根据工作状况实时的改变、通过CAN总线的通信,可以在上位机上实时观测到挖掘机的工作状况,同时根据实际工况做出合理的调整、实验结果表明,通过这样的控制策略和算法,可以大大降低泵功率的损耗。     

Practical motion control with acceleration reference for precision motion—New NCTF control and its application to non-contact mechanism

This paper presents an improved practical controller for enhancing precision motion performance. For practical use, high motion control performance and ease of controller design are desired. A nominal characteristic trajectory following control (NCTF control) has been studied to satisfy the desired response. The NCTF controller consists of a nominal characteristic trajectory (NCT) which is the reference motion of control system and a compensator which makes the motion of the controlled object to follow the NCT. The NCT is easily determined from experimental open-loop time responses of the mechanism. The controller parameters can be also determined easily, without any given model parameters. In the present paper, the Continuous Motion NCTF controller for high continuous motion performance is improved in order to enhance the following characteristic of the object motion on NCT and improve the positioning and tracking accuracies of the system. The improved Continuous Motion NCTF controller (referred to as Acceleration Reference-Continuous Motion NCTF controller (AR-CM NCTF controller)) provides the advantages such as the high overshoot reduction characteristics and the low sensitivity disturbance. The AR-CM NCTF controller includes the structure of the Continuous Motion NCTF controller and acceleration reference for the object motion as the additional controller elements. The design procedure of the AR-CM NCTF controller remains easy and practical. In order to confirm the advantages, the AR-CM NCTF controller was examined in positioning and tracking motion performances using the non-contact mechanism. The experimental results prove that the AR-CM NCTF controller achieves the better positioning and tracking performances than the Continuous Motion NCTF controller.     

A practical control method for precision motion—Improvement of NCTF control method for continuous motion control

The present paper describes a practical control method for a precision motion system and the performance thereof. For practical use, high motion control performance and ease of design and controller adjustment are desired. A nominal characteristic trajectory following control (NCTF control) has been investigated to realize high performance and ease of application of point-to-point (PTP) positioning. The controller comprising a nominal characteristic trajectory (NCT) and a PI compensator is free from exact modeling and parameter identification. In the present paper, the NCTF control is modified in order to improve the control performance of continuous motions such as tracking and contouring motions. The NCTF controller for continuous motion (referred to as Continuous Motion NCTF controller) has a structure that is almost identical to the conventional NCTF controller and is designed using the same design procedure. The Continuous Motion NCTF controller is applied to ball screw mechanisms, and its motion control performance is evaluated from the experimental tracking, contouring, and positioning control results. The experimental results prove that the Continuous Motion NCTF controller achieves the same positioning performance as the conventional NCTF controller, and generally achieves better continuous motion control performances than PI-D or conventional NCTF controllers. In 0.25 Hz and 100-nm radius circular motion, the experimental tracking errors for Continuous Motion NCTF were smaller than 10 nm.     

模糊PID参数自整定控制器的设计

将模糊控制理论与经典的PID控制理论结合,以锅炉温度控制系统为例,设计了一种模糊PID参数自整定控制器.仿真结果表明,和常规PID控制器相比,所设计的模期PID控制器改善了温度控制系统的动态性能,提高了系统的鲁棒性.     

Active surge control for variable speed axial compressors

This paper discusses active surge control in variable speed axial compressors. A compression system equipped with a variable area throttle is investigated. Based on a given compressor model, a fuzzy logic controller is designed for surge control and a proportional speed controller is used for speed control. The fuzzy controller uses measurements of the change of pressure rise as well as the change of mass flow to determine the throttle opening. The presented approach does not require the knowledge of system equilibrium or the surge line. Numerical simulations show promising results. The proposed fuzzy logic controller performs better than a backstepping controller and is capable to suppress surge at different operating points.     

Design of a fractional order PID controller using GBMO algorithm for load–frequency control with governor saturation consideration

Load–frequency control is one of the most important issues in power system operation. In this paper, a Fractional Order PID (FOPID) controller based on Gases Brownian Motion Optimization (GBMO) is used in order to mitigate frequency and exchanged power deviation in two-area power system with considering governor saturation limit. In a FOPID controller derivative and integrator parts have non-integer orders which should be determined by designer. FOPID controller has more flexibility than PID controller. The GBMO algorithm is a recently introduced search method that has suitable accuracy and convergence rate. Thus, this paper uses the advantages of FOPID controller as well as GBMO algorithm to solve load–frequency control. However, computational load will higher than conventional controllers due to more complexity of design procedure. Also, a GBMO based fuzzy controller is designed and analyzed in detail. The performance of the proposed controller in time domain and its robustness are verified according to comparison with other controllers like GBMO based fuzzy controller and PI controller that used for load–frequency control system in confronting with model parameters variations.