一种新型不确定奇异时滞系统的时滞相关稳定性判据及鲁棒镇定

研究了含范数有界参数不确定性的奇异时滞系统的时滞相关状态反馈镇定控制器的设计问题。首先,利用Lyapunov技巧,以LMIs的形式给出了标称奇异时滞系统正则,无脉冲模且零解渐近稳定的一种新的时滞相关型判据。然后,基于广义二次稳定性的概念,以LMIs的形式给出了时滞相关状态反馈镇定控制器存在的一个充分条件。     

不确定离散模糊系统的最优保性能控制

对一类具有范数有界,时变参数不确定性的离散模糊时间系统和一个二次型性能指标,研究其最优保性能状态控制律的设计问题.通过采用线性矩阵不等式的方法,导出了存在保性能控制律的一个充要条件,进而,证明了该条件等价于一组线性矩阵不等式的可解性问题,并用这组线性矩阵不等式的可行解给出了保性能控制律的一个参数化表示.在此基础上,通过建立并求解一个凸优化问题,给出了最优保性能控制律的设计方法.     

离散互联模糊系统的分散控制及稳定性条件

本文针对一类离散互联模糊系统,提出了一种新的模糊分散控制器的设计方法,给出了控制系统稳定的充分条件,应用Lyapunov函数法和线性矩阵不等式理论证明了模糊分散控制系统的稳定性.所提出的模糊分散控制方法和稳定性条件克服了已有模糊分散控制算法的保守性.仿真结果进一步验证了所提的模糊分散控制理论的正确性和方法的有效性.     

Adaptive output feedback sliding mode control for time-delay systems with extended disturbance

This study proposes a new adaptive output feedback sliding mode control (SMC) for mismatched uncertain time-delay systems. First, sufficient conditions in terms of linear matrix inequalities are derived such that the equivalent reduced-order system in the sliding mode is asymptotically stable. Second, based on a new lemma and a novel adaptive law, an adaptive sliding mode controller is designed to guarantee the finite-time reachability of the system states using output feedback only. The proposed method is not limited by the following conditions: (1) the exogenous disturbances must be bounded by a known function of the outputs or by a known function of the state and delayed state variables, and (2) the norm of unmeasured states must be bounded by a constant value. As these conditions are required for the application of most existing SMC approaches for time-delay systems, the proposed approach can be applied to a more generalized system, making it a valuable contribution to the field.     

一类离散非线性时滞互联系统的模糊分散控制

本文对一类离散非线性互联时滞系统,给出了模糊分散状态反馈和基于观测器的分散输出反馈模糊控制方法。设计中,首先采用模糊T-S模型对非线性互联时滞系统进行模糊建模,在此基础上,给出模糊分散状态反馈和基于观测器的模糊分散控制的设计。应用Lyapunov函数方法和线性矩阵不等式方法给出和证明了模糊分散控制系统稳定的充分条件。仿真结果进一步验证了所提出的模糊分散控制方法的有效性。     

一类中立型时滞系统新的鲁棒稳定性准则

本文考虑了一类具有时变时滞和非线性扰动的中立型系统的鲁棒稳定性问题.基于Lyapunov稳定性理论和自由权矩阵方法,得到保证系统鲁棒渐近稳定的新的充分条件.所得结果同时依赖于离散时滞和中立时滞,并用LMIs表示.由于对Lyapunov泛函导数采用了无保守的估计,因此所得结果具有较小的保守性,能够给出时变时滞较大的允许时...     

光电跟踪系统内模控制器的设计

针对光电跟踪系统,提出一种基于内模控制原理的新型位置控制器设计方法。内模控制是一种基于对象数学模型进行控制器设计的新型控制策略,其设计思路是将对象模型与实际对象相并联,控制器逼近模型的动态逆。该控制器设计方法简单,只有一个可调参数,而且可调参数直接与系统的动态特性和鲁棒性相关,与常规 PID 控制器相比,参数调整更加方便。由实验数据统计分析得出,系统的方位跟踪误差和高低跟踪误差的均方根分别为 0.4mrad 和 0.3mrad,表明该控制器能够提高系统的跟踪精度,从而为高性能光电跟踪系统提供了一种新的控制方法。     

广义Vandermonde方程组的有效快速算法

基于求解Vandermonde方程组的Bjorck-Pereyra算法,本文给出了求解广义Vandermonde方程组的有效快速算法,所需的计算量为O(n2)。数值算例表明,与求解Vandermonde方程组的Gohberg-Kailath-Koltracht算法和Gauss消元法相比,本文的算法具有更高的计算精度。     

Improved robust exponential stability for Takagi–Sugeno fuzzy uncertain systems with time-varying delays

This paper concerns managing the robust exponential stability problem of uncertain Takagi–Sugeno fuzzy systems with time-varying delay by employing a further improved integral inequality matrix approach. Based on the linear matrix inequality (LMI) approach, delay-dependent robust exponential stability criteria have been developed. By taking the relationship among the time-varying delay, its upper bound and their difference into account, some less conservative LMI-based delay-dependent robust exponential stability criteria are obtained without ignoring any useful terms in the derivative of Lyapunov–Krasovskii functionals. Maximum allowable upper bound for time-varying delays is determined. Numerical examples are provided to show that the obtained results significantly improve the allowed upper bounds of delay size over some methods existing in the literature.     

矩阵损失下线性混合模型中的局部线性Minimax估计

本文研究了一般线性混合模型中固定效应和随机效应的线性组合的Minimax估计问题.在矩阵损失函数下,考虑了这个组合的线性估计在线性估计类中的局部极小极大性.关于适当的假设,得到了线性可估函数的唯一局部线性Minimax估计.     

Wielandt不等式和Kantorovich不等式的一些推广

本文证明内积空间中的两个不等式,并由这些不等式导出Hilbert空间中关于有界自伴算子、有界可逆算子及正定算子的若干不等式,所获结果推广了关于正定矩阵著名的Wielandt不等式和Kantorovich不等式。同时给出了Cauchy-Schwarz不等式的一些改进形式。最后,作为应用,研究了一些新的积分不等式。     

具有极点约束的线性振动系统的一种主动控制设计:LMI方法

本文讨论具有闭环极点约束的线性振动系统状态反馈主动控制设计问题。极点约束集是左半复平面上一个由圆形和带状区域构成的凸域，以闭环系统的H2指标为优化目标，将该设计问题转化成一个易于计算的线性矩阵不等式（LMI）约束的凸优化问题求解。最后运用本文方法对一个双层隔振系统模型进行状态反馈控制设计，并给出数值仿真结果。     

一种埋弧焊视觉跟踪系统

论述了一种埋弧焊缝视觉跟踪系统的原理,重点讨论了跟踪系统的参数选择和视觉跟踪控制处理部分的组成,实验表明,本系统具有景深大、工作距短、控制准确、可靠性高等特点。     

Feasibility analysis of an OTEC plant as the bottom cycle of the third nuclear power plant

Abstract

A conceptual design, performance analysis, system optimization and simulation of an OTEC (Ocean Thermal Energy Conversion) power plant was carried out in the present study. The OTEC plant acts as the bottom cycle of the Third Nuclear Power Plant, utilizing the warm water discharged from the nuclear plant as the heat source and the cold deep seawater pumped from the nearby sea bottom as the heat sink. The nominal net power output from the OTEC plant is estimated to be 8.74 MWe. A plant simulation was further carried out to study the OTEC plant performance due to seasonal variation of the warm water temperature, which shows that the OTEC plant is able to deliver an electricity of 5.18×10⁷ kWH per year. The net power output in the winter season will be reduced to about one eighth of that in the summer season. The final discharged warm water temperature was shown to be below 29°C all year around, so that the current thermal pollution problem of the nuclear power plant can be eliminated. Additionally there is the side benefit of 8.74 MWe net power generation from ocean energy resource. This OTEC plant will become economically feasible if the installation cost is considered as a thermal pollution control investment.     

Study of the Development Road Map of China’s Renewable Energy

Renewable Energy (RE) has been attached high attention around the world due to its carbon-free and indigenous production in a sustainable way. China enjoys plenty of renewable energy resources, particularly the wind, solar ,hydro and biomass energy, which could be a sound basis for a large-scale exploitation. This report examines the current status of RE technology and industry, analyzes the challenges of promoting RE in China. In order to pave the way for a long-term development of RE, this paper outlines the basic principles and priorities for individual RE technology. In line with these, the paper puts forward the RE targets and further describes the RE Roadmap by 2020, 2030 and extende to 2050, taking consideration of China’s RE resources, industrial basis and energy demand etc. At last, this paper provides some recommendations to ensure the achievements of the RE targets.     

参数不确定振动系统的一种鲁棒主动控制设计

本文讨论具有参数不确定的线性振动系统 ,在随机白噪声激扰作用下的主动控制设计问题。以给定的闭环系统稳态输出方差为约束 ,所需主动控制力的一种代价表示为优化目标 ,将状态反馈二次稳定的主动控制器设计问题 ,转化成一个基于LMIs约束的凸优化问题求解。最后以一个算例说明本文方法。     

热泵在开发可再生能源领域的作用及其贡献率的计算方法

热泵是可再生能源的\"开采机械\",可以用一份电能或机械能,得到数倍的可再生能源,是重要的节能和环保技术。随着我国能源需求剧增和电力工业的快速发展,需要提高我国可再生能源的比例,热泵技术有着极其重要的作用。本文介绍了欧盟把热泵技术列为可再生能源的政策,进而说明了我国相应的政策。通过对我国燃煤电厂的发电效率和电网的输电效率的数据进行分析,得出热泵是获得可再生能源的一种技术。文中提出了我国热泵一次能源倍数α和可再生能源贡献率β两种计算方法供业内参考。由于电厂的烟气排放指标远比一般燃煤锅炉严格得多,用热泵代替燃煤锅炉可改善大气质量。因此本文建议把热泵可再生能源贡献率的计算方法写入国家标准,以促进我国热泵制造产业,大力推广热泵节能技术。     

热声制冷机网络模型中回热器H矩阵参数的测量

对热声系统的网络模型中回热器H矩阵的参数进行了分析,提出了一种H矩阵参数的测量方法。通过实验对简单圆管的无源网络进行测量,与模拟值有较好的吻合,证明实验系统是可靠的。在改变压力和频率的条件下对有源的热声制冷机回热器进行了测量和分析,模拟的结果与测量值基本上一致,流放大系数与模拟的结果偏差较大。说明热声系统是复杂的非线性系统,在线性假设前提下的热声网络模型的模拟结果会存在一定的偏差,尤其在大振幅条件下需要对网络参数进行测量和辨识,通过对网络参数的修正提高模拟的准确性。