共查询到20条相似文献,搜索用时 156 毫秒
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为解决污水处理过程中非线性、大时滞及干扰严重的问题,提出一种将模糊控制器和前馈控制器相接合的控制方法。其中在建立前馈控制器时,提出了使用神经网络建立前馈控制器的新方法。使用这种方法建立前馈控制器无需建立控制系统控制通道和干扰通道的数学模型,也不要求干扰是可以测量的。在MATLAB环境下对控制系统进行仿真,结果表明,将模糊控制和前馈控制结合可以有效克服干扰,提高系统的稳态精度;基于神经网络的前馈控制器可以有效补偿污水处理过程中的干扰,具有实际意义。 相似文献
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针对舰载火炮瞄准对伺服控制系统存在的技术难点.将前馈控制、自适应控制等和PID控制有机的结合起来,构成一种复合式控制器,既提高了系统的抗干扰能力,缩短调节时间,同时又可以兼顾动静态性能. 相似文献
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电子转向助力技术能够有效驱动汽车转向,为提高其转向控制的稳定性和准确性,本文设计了一种基于嵌入式的电子助力转向系统。首先针对传统的电子助力转向系统,利用牛顿第二定律建立其动力学模型,为控制器设计及构建硬件环境奠定基础。其次,针对典型电子转向助力系统的动力学模型,为降低其运动副间的摩擦对控制性能的影响,设计了自适应摩擦前馈补偿控制器,并根据Lyapunov稳定性原则确定了自适应控制率解析表达式。再次,本文以STM32F407嵌入式控制器为核心,搭建系统硬件平台并设计软件流程。最后,基于此平台展开试验验证,系统通过跟踪阶跃指令和正弦指令对比分析了传统PID算法和自适应摩擦前馈补偿算法,试验结果表明自适应前馈补偿算法可提高系统稳态精度和动态响应能力,并验证所设计的基于嵌入式的电子助力转向系统的正确性和完整性。 相似文献
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电锅炉已成为寒冷地区供热采暖的主要设备,对于新疆地区尤为重要.电锅炉的温度控制系统由于存在非线性、滞后性以及时变性等特点,常规的PID控制器很难达到较好的控制效果.考虑到模糊控制能对复杂的非线性、时变系统进行很好的控制,但无法消除静态误差的特点,本设计将模糊控制和常规的PID控制相结合,提出一种模糊自适应PID控制器的新方法.并对电锅炉温度控制系统进行了抗扰动的仿真试验,结果表明,和常规的PID控制器及模糊PID复合控制器相比,模糊自适应PID控制改善了系统的动态性能和鲁棒性,达到了较好的控制效果. 相似文献
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基于参考模型的超声电机模糊自适应控制 总被引:1,自引:0,他引:1
针对由日本新生公司生产的USR系列超声电机构成的速度伺服系统提出了一种新的控制方案——基于参考模型的模糊自适应控制。该控制器由参考模型、PI控制器、模糊自适应调节器构成,PI控制器的比例系数的增量△Kp和积分系数的增量△Ki根据模糊自适应调节器模糊推理的结果确定,使得控制器的参数能够随着被控对象参数的变化而改变,从而保证系统的响应跟踪参考模型的输出响应。实验结果表明该控制方案优于一般的PI控制器和模糊PI控制器,并且简单易行,通用性强。 相似文献
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为解决传统的自适应模糊控制器算法过于复杂难以用模拟电路实现的问题,本文研究了输入输出论域可随输入变量的变化而自适应变化的在线自适应模糊控制器及其在非线性系统控制中的应用,并制作了CMOS模拟电路芯片.提出了一种新的尖三角形隶属度函数实现输入变论域的功能,输出变论域部分采用对输入变量进行加权积分并求其绝对值的方法.控制器的其他部分为求小电路和重心法去模糊电路.以上各电路均为CMOS模拟电路,它们和集成的整体电路均在无锡上华(CSMC) 0.6μm工艺下流片,测试结果表明该芯片完成了变论域模糊控制器的功能. 相似文献
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Wei-Shiu Wang Chang-Huan Liu 《Industrial Electronics, IEEE Transactions on》1992,39(5):379-391
A control strategy which consists of feedforward and feedback compensation loops is proposed to improve the performance of industrial robots. The feedforward loop is similar to the usual inverse-dynamics compensation. The feedback control loop uses a frequency-domain optimal controller. The design starts from the single-link case and is extended to the control of multilinkage flexible-joint robots. An experimental system consisting of a single-link robot is constructed for verifying the proposed control strategies. Experiments show good performance of the proposed control strategy in stiffening the flexible joint and in tracking desired polynomial-type trajectories 相似文献
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《Mechatronics》2015
Tendon–sheath mechanism (TSM) has inherent advantages in the development of flexible robotic systems because of its simplicity, safety, flexibility, and ease of transmission. However, the control of TSM is challenging due to the presence of nonlinearities, namely friction, backlash-like hysteresis and the time-varying configuration of the TSM during its operations. Existing studies of TSM found in the literature only address tendon transmission under the assumption of fixed configuration and a complex inverse model of backlash is required. In order to flexibly use the system in a wider range of applications, the aforementioned nonlinear effects have to be characterized for the purpose of compensation. In this paper, we endeavor to address these issues by presenting a series of controller strategies, namely a feedforward control scheme under the assumption of known backlash-like hysteresis profile, and an adaptive control scheme to characterize the nonlinearities with unknown backlash hysteresis and uncertainties. The proposed control schemes do not require information of the tendon–sheath configurations, which is challenging to obtain in practice, in the compensation structures. In the absence of output position feedback, a simple direct inverse model-based feedforward has been used that efficiently reduce the tracking errors. The feedforward compensation does not require any complex algorithm for the inverse model. In the presence of output position feedback, a nonlinear adaptive controller has been developed to enhance the tracking performances of the TSM regardless of the random change in the tendon–sheath configurations during compensation. In addition, exact values of the model parameters are not required. They are estimated online during the operations. A dedicated experimental setup is introduced to validate the proposed control approaches. The results show that the proposed control schemes significantly improve the tracking performances for the TSM in the presence of uncertainties and time-varying configurations during the operations. There is a significant decrease of 0.0158 rad2 (before compensation) to smaller value of 0.0012 rad2 (use feedforward control) and 8.2815 × 10−5 rad2 (use nonlinear controller) after compensation. 相似文献
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该文对压电驱动器建模与控制技术进行了研究。通过二阶系统描述了压电驱动器的线性动态特性。基于Preisach迟滞模型,提出了全新的简化模型,避免了Preisach模型中复杂的双重积分运算。通过前馈与反馈控制技术相结合,为压电驱动器设计了一个综合控制器。在前馈控制器中,通过Preisach模型描述逆迟滞环,有效解决了Preisach模型不可逆的问题。通过比例、积分、微分(PID)反馈控制器,有效提高了系统鲁棒性,并有效补偿了前馈控制器中模型不精确带来的误差。最终,通过实验分别验证了模型的有效性及控制器的控制作用。 相似文献
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为了提高空间天文望远镜精密稳像系统中大口径压电快摆镜机构(Fast Steering Mirror,FSM)的控制精度,采用迟滞前馈补偿和最优PID控制算法相结合的复合控制策略。针对基于广义Play算子的Prandtl-Ishlinskii(PI)模型可逆性受约束条件限制以及求逆过程中模型参数估计误差累加的问题,提出了一种基于广义Stop算子的PI逆模型进行压电执行器(Piezoelectric Actuator,PZT)迟滞补偿。针对逆迟滞模型的不确定性和直接前馈控制抗干扰能力差的问题,在控制系统中加入最优PID闭环控制器。采用自适应差分进化算法(Adaptive Differential Evolution,ADE)对迟滞逆模型参数和PID控制器参数进行寻优并引入混沌搜索机制来提高ADE算法的性能。实验结果表明:与传统PI模型解析求逆方法相比,基于广义Stop算子的PI逆模型能够更好描述逆迟滞曲线,拟合频率为1 Hz的迟滞曲线,拟合精度提高78.04%;实时跟踪频率分别为1、10、20 Hz的大口径快摆机构目标摆动位移,复合控制策略的跟踪精度相比于直接前馈控制分别提高了38.56%,22.92%和13.5%。 相似文献
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A current-mode buck DC-DC controller based on adaptive on-time (AOT) control is presented. The on-time is obtained by the techniques of input feedforward and output feedback, and the adaptive control is achieved by a sample-hold and time-ahead circuit. The AOT current-mode control scheme not only obtains excellent transient response speed, but also achieves the independence of loop stability on output capacitor ESR. In addition, the AOT current-mode control does not have subharmonic oscillation phenomenon seen in fixed frequency peak current-mode control, so there is no need of the slope compensation circuit. The auto-skip pulse frequency modulation (PFM) mode improves the conversion efficiency of light load effectively. The controller has been fabricated with UMC 0.6-μm BCD process successfully and the detailed experimental results are shown. 相似文献
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Vibration Suppression Using Single Neuron-Based PI Fuzzy Controller and Fractional-Order Disturbance Observer 总被引:3,自引:0,他引:3
Wen Li Yoichi Hori 《Industrial Electronics, IEEE Transactions on》2007,54(1):117-126
An approach is proposed for vibration suppression in a two-inertia system using an integration of a fractional-order disturbance observer and a single neuron-based PI fuzzy controller. The former is used to obtain disturbance estimate and generate compensation signal, and the latter is utilized to realize outer loop control. Fractional-order disturbance observer has a wider range to select a suitable tradeoff between robustness and vibration suppression, because introduction of fractional calculus makes universe of relative degree of Q-filter is expanded from integer domain to real-number domain. For the single neuron-based PI fuzzy controller, a single neuron makes up a PI controller and such a controller is embedded in each cell of the fuzzy control table. Thus, the fuzzy control table is changed into a controller matrix and it constructs a nonlinear adaptive controller with parameter self-tuning property. Experimental results illustrate that the integration of fractional-order disturbance observer and single neuron-based PI fuzzy controller can improve the performance of disturbance attenuation and system robustness 相似文献