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41.
This paper is concerned with the problem of the fault detection filter design for discrete‐time switched linear systems with average dwell‐time. The designed fault detection filters are also switched systems, which are assumed to be asynchronously switched with the original switched systems. Improved results on the weighted l2 performance and the H ? performance are first given, and the multiple Lyaounov‐like functions during matched period and unmatched period for the running time of one subsystem are used. By the aid of multiple Lyapunov‐like functions combined with Projection Lemma, the FD filters are designed such that the augmented systems under asynchronous switching are exponentially stable, and the residual signal generated by the filters achieves the weighted l2‐gain for disturbances and guarantees the H ? performance for faults. Sufficient conditions are formulated by linear matrix inequalities, and the filter gains are characterized in terms of the solution of a convex optimization problem. Finally, examples are provided to demonstrate the effectiveness of the proposed design method. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
42.
This paper presents some further results on adaptive sliding mode control (ASMC) for a class of nonlinear systems with bounded uncertain parameters. Given a large initial tracking error, current ASMC design generally produces an unnecessarily large switching gain, consequently leading to a serious chattering problem or a large‐amplitude control jump for the continuous counterpart. To solve such an overadaptation problem, the switching gain adaptation mechanism is first analyzed in this paper, and the adaptation induced by the initial tracking error is suggested to be removed. Then, by exploiting the global sliding mode feature of time‐varying sliding mode control and integral sliding mode control, we present two effective methodologies for ASMC design. The proposed ASMC algorithms ensure that there is no overestimation of the switching gain and the system response is not slowed down when a small switching gain is generated. The validity of the proposed methods is verified by both theoretical analysis and simulation results. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
43.
In this paper, the control synthesis problem for a class of large‐scale systems with multi‐modes that are called large‐scale switched systems is addressed. By introducing the concept of decentralized switching signal and the relevant decentralized average dwell time, the asymptotic stability and weighted ?2 gain performance are investigated. It should be noted that the decentralized switching covers general switching cases for large‐scale switched systems, namely, it admits both time‐dependent switching signal and arbitrary switching signal blended in the decentralized switching. Then, on the basis of the analysis results, the decentralized weighted control scheme including state feedback controller gains and switching signals is studied. Several design algorithms are proposed to meet different controller design problems. Finally, numerical examples are provided to illustrate theoretical findings within this paper. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
44.
以功率MOSFET和IGBT为代表的、集高频、高压和大电流于一身的功率半导体复合器件,表明传统电力电子技术已经进入现代电力电子时代,开关电源的工作频率得以大大提高,一些新技术的应用更是进一步提升了开关电源的性能。开关电源拥有更广阔的发展空间和应用前景。 相似文献
45.
鹿优 《山东电力高等专科学校学报》2010,13(1):61-64
本文着重介绍了自激多谐振荡器的电路仿真过程。首先阐明了对称的自激多谐振荡器的工作原理;其次应用电路仿真软件Multisim10对自激多谐振荡器进行了简捷的仿真分析;最后以脉冲信号发生器为例说明了自激多谐振荡器的应用问题。 相似文献
46.
研究了一种线性F∕V转换系统。利用单片机来检测正弦波的频率,根据检测的频率确定D/A转换的数字量,控制TLC5615串行D/A芯片将频率信号转变为电压信号,使输出电压与频率大小呈线性关系,而且它们的线性关系是不经过原点的直线,而现有的F/V转换的器件都不能满足这种要求。 相似文献
47.
针对电子战中各种信号混叠严重难以分离的现象,在盲源分离开关算法基础上提出一种新的盲信源分离拟开关算法.该算法引入单位对称加权滑动向量来加权每次迭代所得的分离信号作为源信号,用峭度取代原算法的峭度符号位作为判断函数来自适应选择加权相应激活函数,以此优化学习算法,结合信号分选的具体应用,给出了迭代结束的评判方法.计算机仿真实验表明,在强噪声背景影响下,该算法能够更加有效地分离空间未知多源线性混叠信号,且在分离效果、稳定性、处理速度和抗噪性能上都比原算法有较大改进. 相似文献
48.
49.
针对传统开关电源存在的控制芯片供电方式耗能较大、反馈电路光耦有效输入电流范围窄两个问题,对传统电源电路进行了改进,设计并实现了一款性能优良的48V转+5V、±15V,输出功率25W的三路输出反激式开关电源。样机输出电压精度为0.2%(+5V)、0.53%(+15V)、0.6%(-15V),输出电压纹波为20mV(+5V)、50mV(+15V)、60mV(-15V),电压精度和纹波率均满足小于1%的要求;测试表明:该电源性能优良,具有效率高,稳压精度高,负载调整率高等优点,有很高的生产应用价值。 相似文献
50.
In this article, we study the delay‐dependent stability of a class of hybrid neutral stochastic differential equations (NSDEs) with multiple delays which is highly nonlinear. Some novel stability criteria are investigated according to Lyapunov functions and generalized Itô's formula. In particular, we generalize and improve the results in Shen et al, Systems & Control Letters (2018) from a single delay to multiple delays. 相似文献