Proportion Integration Differentiation(PID)Control Strategy of Belt Sander Based on Fuzzy Algorithm

Aiming at solving the problems of response lag and lack of precision and stability in constant grinding force control of industrial robot belts,a constant force control strategy combining fuzzy control and proportion integration differentiation(PID)was proposed by analyzing the signal transmission process and the dynamic characteristics of the grinding mechanism.The simulation results showed that compared with the classical PID control strategy,the system adjustment time was shortened by 98.7%,the overshoot was reduced by 5.1%,and the control error was 0.2%-0.5%when the system was stabilized.The optimized fuzzy control system had fast adjustment speeds,precise force control and stability.The experimental analysis of the surface morphology of the machined blade was carried out by the industrial robot abrasive grinding mechanism,and the correctness of the theoretical analysis and the effectiveness of the control strategy were verified.

Fuzzy Self-adaptive Proportional Integration Differential Control for Attitude Stabilization of Quadrotor UAV

The technology of attitude control for quadrotor unmanned aerial vehicles(UAVs) is one of the most important UAVs' research areas.In order to achieve a satisfactory operation in quadrotor UAVs having proportional integration differential(PID) controllers,it is necessary to appropriately adjust the controller coefficients which are dependent on dynamic parameters of the quadrotor UAV and any changes in parameters and conditions could affect desired performance of the controller.In this paper,combining with PID control and fuzzy logic control,a kind of fuzzy self-adaptive PID control algorithm for attitude stabilization of the quadrotor UAV was put forward.Firstly,the nonlinear model of six degrees of freedom(6-DOF) for quadrotor UAV is established.Secondly,for obtaining the attitude of quadrotor,attitude data fusion using complementary filtering is applied to improving the measurement accuracy and dynamic performance.Finally,the attitude stabilization control simulation model of the quadrotor UAV is build,and the self-adaptive fuzzy parameter tuning rules for PID attitude controller are given,so as to realize the online self-tuning of the controller parameters.Simulation results show that comparing with the conventional PID controller,this attitude control algorithm of fuzzy self-adaptive PID has a better dynamic response performance.

Adaptive proportional integral differential control based on radial basis function neural network identification of a two-degree-of-freedom closed-chain robot

A closed-chain robot has several advantages over an open-chain robot, such as high mechanical rigidity, high payload, high precision. Accurate trajectory control of a robot is essential in practical-use. This paper presents an adaptive proportional integral differential （PID） control algorithm based on radial basis function （RBF） neural network for trajectory tracking of a two-degree-of-freedom （2-DOF） closed-chain robot. In this scheme, an RBF neural network is used to approximate the unknown nonlinear dynamics of the robot, at the same time, the PID parameters can be adjusted online and the high precision can be obtained. Simulation results show that the control algorithm accurately tracks a 2-DOF closed-chain robot trajectories. The results also indicate that the system robustness and tracking performance are superior to the classic PID method.

冷链运输车空调冷风机运行自适应PID控制方法研究

冷链运输车空调冷风机运行环境复杂,导致传统的比例积分微分(PID)控制过程难以准确设定控制参数。为解决这一问题,设计冷链运输车空调冷风机运行自适应PID控制方法。首先,通过分析冷链运输车空调冷风机工作过程,选取多个控制参数,以降低复杂度。然后,设计基于自适应PID控制器的控制模型,以送风温度和送风压力作为控制量,将冷、热水流量及风机转速作为被控制量,求解控制量和被控制量的传递函数。最后,根据传递函数与期望值间的耦合关系,对控制分量的增减进行调整,以实现冷链运输车空调冷风机运行的自适应PID控制。试验结果表明,该方法能够使冷链运输车内温度保持稳定。该方法控制精准度高、鲁棒性强、实用价值高,可以确保货物在整个冷链运输过程中的质量和安全。

基于APID-RBF神经网络的光伏MPPT方法

针对光照强度急速变化和局部阴影时光伏发电系统最大功率点追踪响应速度慢、多峰值等问题,提出一种基于RBF神经网络与自适应PID控制相结合的控制方法。首先,采用RBF神经网络对环境的实时变化直接跟踪光伏最大功率点。然后,利用自适应PID的辅助修正,抑制光伏电池输出功率的波动。神经网络能提升在复杂环境下的跟踪速度,自适应PID能增强对神经网络误差的消除能力,提升跟踪精度。仿真结果表明,APIDRBF双控策略具有稳态性能高和控制精度高等优点,能有效提高光伏发电效率和稳定性。

基于模糊PID的打磨头角度控制策略研究

在进行风电机组叶片表面打磨工序时,需要控制打磨头的径向与叶片表面保持垂直。对打磨头的角度调整问题进行分析和研究,通过分析打磨头的结构构成与运动轨迹,建立打磨头伺服系统的数学模型。基于角度变化引起的重力转矩补偿量,提出一种模糊比例-积分-微分(Proportion-Integral-Differential,PID)的角度伺服控制系统。Simulink仿真验证结果表明,重力补偿后模糊PID控制方法的打磨头伺服系统响应速度更快、误差更小,能够较好地调整打磨头的角度。

基于遗传算法整定驱动参数的水力发电机PID控制

为了弥补PID控制容易出现超调的现场,设计了一种基于遗传算法整定驱动参数的水力发电机PID控制方法。从正弦信号方面对水力发电机开展进给测试,促进了跟随性能的显著提升。研究结果表明:遗传算法整定方案在迭代到37次时达到收敛,幅频特性表明系统获得了理想响应性能。采用遗传算法整定驱动参数后获得更低跟随误差,表现出了更优的跟随性能。正弦信号下遗传算法参数整定时达到了更低跟随误差,表现出了更优的跟随性能。绝对误差极值降低35.5%,绝对误差积分降低50.1%。该研究有助于提高水力发电机控制稳定性,也可适用于其它的机械传动机构。

基于BP神经网络的Fuzzy-PID恒温控制器

在高精度恒温系统温度控制中,为了克服温度这种被控对象因其纯滞后、非线性和大惯性特性以及被控对象参数的时变性对精度的影响,采用了BP神经模糊PID控制器代替模糊控制,使推理速度加快,并通过在系统运行时不断地增加和完善模糊控制规则,不断提高系统控制的精度。仿真分析结果表明,经过BP神经网络优化学习后,系统具有良好的控制性能和自适应能力,很好地满足了大滞后系统对高精度控温与快速性的要求。

基于模糊神经网络PID的无人艇航向控制器研究

针对常规比例、积分和微分(proportional integral derivative,PID)控制器在无人艇航向控制系统中表现出的稳定性差、控制精度低等问题,文章提出一种将模糊控制与反向传播(back propagation,BP)神经网络相结合的控制算法;在MATLAB中对比常规PID控制器、模糊PID控制器与模糊神经网络PID控制器在给定期望航向角下的航向控制性能,仿真结果表明模糊神经网络PID控制器对无人艇的航向控制性能最佳;在搭建的实验平台上对不同航向控制器下无人艇的航行轨迹和航向角进行比较,实验结果进一步验证了模糊神经网络PID航向控制算法的优越性。

静止无功补偿器的小波神经网络PID控制方法研究

静止无功补偿器(SVC)是电力系统中应用广泛的动态无功补偿装置。针对传统比例积分微分(PID)在SVC动态调节过程中由于控制器参数固定而存在动态响应、自适应能力差的问题,提出了一种基于小波神经网络PID(WNNPID)的SVC电流反馈电压稳定控制方法。首先,分别选取SVC的电压差ΔUr、电压误差ΔU和补偿电压USL作为WNNPID控制器的输入信号,而控制器的输出为SVC的参考电纳。然后,采用小波神经网络(WNN)和增量式PID控制对WNNPID控制器的结构进行设计。最后,采用Matlab/Simulink仿真平台对所提控制方法进行仿真,并与基于反向传播(BP)神经网络PID的控制效果进行了对比。仿真结果表明,所提WNNPID控制方法具有更稳定的电压控制效果、较快的响应速度、较好的动静态响应性能和较强的自适应能力。

Fuzzy PID control system for hose pulse experiment based on LabVIEW

The hose pulse testing bench generally uses electro-hydraulic servo system. It occupies little space, tracks signals fast and has simple structure, and therefore it is widely used in industrial control field. However, there are lots of problems such as little accuracy and instability caused by slow response of hydraulic and various interference factors. Simple proportional integra- tion derivatiation （PID） control method of traditional pulse bench is simple in principle, but it is difficult in parameter adjust- ment. According to the special requirements of the control system, a PID method based on fuzzy control is proposed in the pa- per. This method not only retains the advantages of the conventional control system, but also ameliorates the drawbacks of parameter uncertainty, instability and lag. It has been testified that the method is practicable and can improve the precision and adaptation.

基于非线性PID的微电网虚拟同步发电机控制

为解决传统虚拟同步发电机(VSG:Virtual Synchronous Generator)电压电流双闭环控制的抗扰动性能差,受系统参数变化及各种不确定影响较大等问题,在建立微电网VSG转动惯量自适应控制模型的基础上,采用一种基于跟踪微分器的非线性PID(Proportion Integration Differentiation)实现电压外环和电流内环的控制,并根据输出信号的反馈值实时调节系统动态响应,从而达到稳定输出的效果。通过仿真验证了基于非线性PID的微电网虚拟同步发电机双闭环控制的正确性和有效性。

基于模糊规则的地面式储能系统自适应PID控制

城市轨道交通地面式储能系统采用电压环串电流环的结构,根据直流网电压来控制其充放电。此处对地面式超级电容储能系统DC/DC变换器电压外环控制动态响应速度和稳定性进行了优化研究,利用传递函数分析了牵引网电压、超级电容电压和电感电流变化对电压环电流环性能的影响,结果表明超级电容电压、牵引网电压共同影响充电电压环动态响应速度;其次考虑电压环引入滞环判断,分析由于滞环带来的非线性特性对充电电压环稳定性的影响,结果表明滞环在一定条件下会对充电电压环的稳定性造成影响;在所分析的问题基础上,提出了充电电压环模糊自适应比例积分微分(PID)控制策略,改善了充电电压环动态响应速度和稳定性。

基于模糊PID的山地拖拉机调平控制系统的设计

在自行开发的山地拖拉机调平机构上加装了自动调平控制系统。系统以可编程逻辑控制器(PLC)为主控核心,以倾角传感器为车身平台倾角检测机构,以模糊PID为调平控制算法,通过监测倾角传感器检测的角度值来实时调整伺服电机的转动与伺服电缸的伸缩,以实现车体平台的自动调平。静态试验结果表明,拖拉机车体平台在倾斜15°的情况下,车体平台横向和纵向单独完成调平分别用时1.851 s和1.882 s,同时调平在3.319 s内完成。动态试验结果表明,拖拉机在行驶速度1.73 km/h、最大坡度15°时,完成车体平台横向和纵向调平分别用时6.253 s和6.853 s;调平时最大超调角分别为9.053 3°和8.687 2°,调平后车体平台角度偏差最终可控在0.5°。

基于GA优化的模糊PID塑料挤出机温度控制系统设计

在塑料挤出机生产加工过程中,温度的响应速度和稳定性是影响塑料产品质量的关键因素。为解决塑料挤出机温度系统存在滞后性、高超调量和抗干扰能力低等问题,在传统比例-积分-微分(PID)控制方式和模糊PID控制方式的研究基础上,提出基于遗传算法优化的模糊PID塑料挤出机温度控制系统。新系统设计结合了塑料挤出机的主要结构功能和工艺参数,对塑料挤出机模糊PID控制系统参数进行优化,应用遗传算法对模糊控制器隶属函数进行动态优化,降低模糊规则的主观和盲目性。此外还利用MATLAB与Simulink环境进行仿真,通过3组控制方式的仿真波形曲线对比分析得出,基于遗传算法(GA)优化的模糊PID在控制效果方面优于模糊PID控制和传统PID控制,且其控制系统无超调、上升时间短、抗干扰能力强。因此基于GA优化的模糊PID塑料挤出机温度控制系统稳定性更强、温度控制精度更高,满足了塑料挤出机对温度控制精度的要求。

车辆磁流变半主动悬架变论域模糊PID控制

在传统比例积分微分(Proportional Integral Derivative,PID)控制的基础上,考虑到论域因子的误差,设计了一种函数型的变论域模糊PID控制策略。基于1/4车辆二自由度磁流变半主动悬架系统,首先,建立了磁流变阻尼器的正、逆模型;然后,根据车辆磁流变半主动悬架系统的振动特性建立了模糊推理规则;最后,基于变论域的思想,设计了模糊论域的伸缩因子,以获得最优的控制精度。利用Matlab/Simulink软件在随机路面和正弦路面分别对车辆磁流变半主动悬架进行了仿真分析,通过车身垂直加速度、悬架动挠度以及车轮动载荷进行悬架性能评价,结果表明,与被动悬架、模糊控制和模糊PID控制相比,变论域模糊PID控制使车辆磁流变半主动悬架各性能指标均得到有效改善。

PID-Based Bit Allocation Strategy for Asymmetric Stereoscopic Video Coding with Fuzzy Quality Controller

Asymmetric stereoscopic video coding can take advantage of binocular suppression in human vision by representing one of the two views in lower quality.This paper proposes a bit allocation strategy for asymmetric stereoscopic video coding.In order to improve the accuracy of bit allocation and rate control in the left view,a proportionalintegral-derivative controller is adopted.Meanwhile,to control the quality fluctuation between consecutive frames of the left view,a quality controller is adopted.Besides,a fuzzy controller is proposed to control the variation in quality between the left and right views by comparing the PSNR disparity of two views with a fixed threshold,which is used to quantize the binocular psycho-visual redundancy and adjust the quantization parameter (QP) of the right view correspondingly.The proposed algorithm has been implemented in H.264/AVC video codec,and the experimental results show its effectiveness in rate control while keeping a good quality for the left view,and fewer bits are allocated for the right view so that the overall bit rate is saved by 7.2% at most without the loss of subjective visual quality for stereoscopic video.

基于PID型H_(∞)滤波算法估计锂离子电池的SOC

针对H_(∞)滤波算法(HIF)对系统状态和模型不确定性突变不敏感的问题,提出一种比例-积分-微分(PID)控制的H_(∞)滤波算法(PID-HIF),以提高荷电状态(SOC)估计的准确性。放电测试中,采用自适应遗忘因子最小二乘(AFFRLS)算法进行系统参数辨识,采用HIF进行SOC估计,与扩展卡尔曼滤波(EKF)算法相比,SOC估计的均方根误差由3.375 3%降低至2.415 8%;在HIF的基础上添加PID控制思想后,均方根误差进一步降低至0.739 3%。在动态应力测试条件下,EKF、HIF和PID-HIF等3种算法的SOC均方根误差分别为4.103 8%、2.414 1%和0.069 4%。

基于ANFIS-PID的大运距矿石输送控制系统设计

针对港口大运距分送式矿石输送控制系统调速不稳定造成堵料停机事故和系统运行能耗高的问题,设计了基于比例积分微分功能的自适应神经元模糊推理系统(ANFIS-PID)的大运距矿石输送控制系统。系统采用了ANFIS-PID,用于精确调节矿石输送系统的带速。讨论了系统实现的技术关键点。结合系统功能的实际需求,主要从系统的控制对象、网络总体结构设计、ANFIS-PID的程序优化设计、ANFIS-PID仿真对比试验分析、计算机监控系统设计等5个方面进行阐述。实际运行表明:该系统与传统矿石输送控制系统相比,具有带速调节精度高、运行能耗低、系统安全可靠等优点,实现了良好的节能调速效果。

基于二自由度PID的三相PWM整流器调压改进策略

基于前端电压源型整流器(voltage source rectifier,VSR)与后端电压源型逆变器(voltage source inverter,VSI)级联的VSR-VSI双三相脉冲宽度调制(pulse width modulation,PWM)变换器已在电梯能量回馈系统中得到广泛应用,但前端三相VSR采用传统比例积分(proportional integral,PI)双闭环控制结构通常存在中端直流母线电压无法兼顾抗干扰性和跟踪性的问题。为此,文中提出一种基于二自由度比例积分微分(proportional integral differential,PID)的三相PWM整流器调压改进策略。首先,阐述基于VSR-VSI双三相PWM变换器级联系统的结构和工作原理,并给出前端三相VSR的传统PI双闭环控制方案及其参数设计过程,分析该方案不能兼具良好的抗干扰性与跟踪性的原因。在此基础上,给出基于二自由度PID的前端三相VSR直流调压优化策略及其参数设计方法。最后,利用软件仿真与实验测试对比结果共同验证了所述三相PWM-VSR直流调压改进策略的有效性与优越性。