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981.
The dynamic output feedback control problem with output quantizer is investigated for a class of nonlinear uncertain Takagi‐Sugeno (T‐S) fuzzy systems with multiple time‐varying input delays and unmatched disturbances. The T‐S fuzzy model is employed to approximate the nonlinear uncertain system, and the output space is partitioned into operating regions and interpolation regions based on the structural information in the fuzzy rules. The output quantizer is introduced for the controller design, and the dynamic output feedback controller with output quantizer is constructed based on the T‐S fuzzy model. Stability conditions in the form of linear matrix inequalities are derived by introducing the S‐procedure, such that the closed‐loop system is stable and the solutions converge to a ball. The control design conditions are relaxed and design flexibility is enhanced because of the developed controller. By introducing the output‐space partition method and S‐procedure, the unmatched regions between the system plant and the controller caused by the quantization errors can be solved in the control design. Finally, simulations are given to verify the effectiveness of the proposed method. 相似文献
982.
针对多点任意转角连续盘车数据,提出了一种基于改进遗传算法提取正弦信号参数的求解方法。基于MATLAB遗传算法工具箱,以牡丹江电厂为例,对盘车数据进行了仿真研究,数据结果表明,该方法具有精度高和全局收敛的优点。 相似文献
983.
Ioan Doré Landau Marouane Alma Aurelian Constantinescu John J. Martinez Mathieu Noë 《Control Engineering Practice》2011,19(10):1168-1181
The paper addresses the problem of attenuation (rejection) of unknown and time varying multiple narrow band disturbances without measuring them. In this context the disturbance model is unknown and time varying while the model of the plant is known (obtained by system identification) and almost invariant. This requires to use an adaptive feedback approach. The term “adaptive regulation” has been coined to characterize this control paradigm. Application domains include: mechanical and mechatronics systems, active vibration and noise suppression systems, some types of bio-chemical reactors.The paper reviews the various techniques proposed for solving this problem. It will focus on the presentation of the direct and indirect adaptive regulation strategies using the internal model principle and the Youla–Kucera parametrization which have been extensively used in applications.The paper also reviews a number of applications including: active suspension systems, active vibration control systems, active noise control, bio-chemical reactors, distributed flexible mechanical structures and Blu-ray disc drives. Real time results obtained on various applications will illustrate the methodology. 相似文献
984.
In this paper, we develop a nonlinear controller to achieve output tracking for a nonminimum phase vertical take‐off and landing aircraft without velocity measurements. To attenuate the effects of input disturbances and unmatched uncertainties, auxiliary control inputs are introduced in the state observer. Then by taking the aircraft lateral movement into consideration, a control law is proposed to force the vertical take‐off and landing aircraft to asymptotically track the desired trajectories even in the presence of unexpected changes of the trajectories, while driving the unstable internal dynamics to follow the bounded and causal ideal internal dynamics via the stable system center method. Numerical simulation results illustrate the effectiveness and robustness of the proposed controller. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
985.
正弦输入法识别电液伺服阀的动特性 总被引:4,自引:0,他引:4
该文对用传统的正弦信号输入法识别电液伺服阀动特性的理论和实践进行了探讨。设计了试验方案并编制了确定电液伺服阀数学模型的计算机拟合程序。通过辨识,对一般力反馈型两级电液伺服阀的合理的数学模型也进行了探讨。 相似文献
986.
The present study explores the effect of upstream disturbances like a single 90°bend, double 90° bends (in plane and out of plane) on the performance of wafer cone flowmeters with same beta ratio (β) of 0.77 but different half cone angles (α) of 30° and 45°. The influence of these disturbances on the upstream and downstream axial velocity (u) profiles are studied experimentally. The orientation effects, if any, are also studied experimentally. The minimum upstream distances required to get a fully developed flow for these disturbances vary with type of upstream disturbance, beta ratio (β) and half cone angle (α) of the wafer cone flowmeter. The study is carried out for a single phase flow with air as working medium at high Reynolds number (ReD = 144000). From the results obtained from this study, it may be concluded that the wafer cone flowmeter with a beta ratio (β) of 0.77 and a cone angle of 30° requires less upstream distance compared to the wafer cone flowmeter with a beta ratio (β) of 0.77 with a cone angle of 45° for all the disturbances under consideration. 相似文献
987.
Subsynchronous oscillations in a power system with series-compensated lines can be amplified and sustained because of interaction between the electrical power system and the turbine generator system. Recently, it has been found that an HVDC link may have a similar effect. A subsynchronous resonance study is described for an EHV series-sompensated ACDC transmission system performed on a digital computer which includes mathematical modelling of a synchronous machine with torsional dynamic representation. Owing to the fast controllability of HVDC transmission, a simple DC current regulator can be incorporated into the rectifier current control system to modulate the DC power whereby the rather fast (10–20 Hz) torsional oscillations can be damped out. This power mudulation can be used for the damping of oscillations caused by the series-compensated AC line as well as by an HVDC link. 相似文献
988.
U. Di Caprio 《International Journal of Electrical Power & Energy Systems》1982,4(4):224-232
Taking account of the structural conditions for theoretical coherency, a single machine equivalent circuit is determined. This is an extension of the Thévenin theorem to electromechanic circuits and will be used as the basis for constructing a practical dynamic equivalent in the second part of the paper. 相似文献
989.
黄登山 《西安电子科技大学学报(自然科学版)》1993,20(4):51-58
基于正弦波信号模型,文中提出了一种简单的线性预测谱估计修正算法。首先,用流行的有效算法求得线性预测误差滤波器系数矢量A',然后简单地令a0=1-Wopt构造新的线性预测误差滤波器系数矢量A'0。理论和计算机模拟实验都显示这种算法对提高谱估计性能效果显著。 相似文献
990.