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1.
状态估计是电力系统能量管理系统的重要组成部分.传统加权最小二乘估计不具备抗差性,为此产生了抗差估计理论.本文介绍了抗差估计的定义、目标及基本类型,综述了电力系统抗差状态估计的经典方法和新方法.经典方法主要包括M估计、GM估计、高崩溃污染率估计等;新方法包括新息图状态估计、最大相关熵估计、最小信息损失状态估计、最多赞成状...  相似文献   

2.
This paper proposes a new modeling approach that is experimentally validated on piezoelectric systems in order to provide a black‐box pseudolinear model for complex systems control. Most of the time, one uses physical based approaches. However, sometimes complex phenomena occur in the system due to atypical changes of the process behavior, output noise or some hard nonlinearities. Therefore, we adopt identification methods to achieve the modeling task. The microdisplacements of the piezoelectric systems generate atypical data named outliers, leading to large estimated prediction errors. Since these errors disturb the classical normal probability density function, we choose here, as corrupted distribution model, the gross error model (GEM). In order to deal more efficiently with the outliers, we use the Huber's function, as mixed L2/L1 norms in which the tuning threshold named scaling factor is extended. From this function, a cost function also named PREC as parameterized robust estimation criterion is established. The identification is performed by choosing an Output Error model structure. In order to express the asymptotic covariance matrix of the robust estimator, we present a L finite Taylor's expansion to linearize the gradient and the hessian of the PREC. Experimental results are presented and discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

3.
杨睿  张向文 《电源技术》2022,46(1):63-67
为提高等效电路模型准确性,考虑等效电容分数阶本质和锂电池充放电不同阶段的不同变化特性,采用分数阶微积分理论建立了基于二阶RC模型的电池分段分数阶等效电路模型.用粒子群算法分段辨识分数阶阶数,通过混合脉冲功率特性(HPPC)实验辨识模型参数,使模型更符合电池实际工作状态.实验结果显示,新模型能够更准确地模拟电池充放电特性...  相似文献   

4.
为了提高船舶电力系统的稳定性,同时研究建立分散励磁式船舶电力系统数学模型的方法,以三台发电机并联运行的工况为例,考虑了发电机角速度、母线端电压以及电动机转子侧电流扰动等不确定性因素,以同步旋转坐标系为参考系分解,建立了解耦后的柴油发电机组、异步电动机、馈线、静态负载的数学模型.根据鲁棒控制理论,设计了船舶电力系统的H∞状态反馈控制器,并应用线性矩阵不等式求解了该控制器.仿真结果表明,当模型的各种扰动信号为脉冲信号时,系统响应能在较短的时间内收敛到0,稳定时间约为0.3s,表明所设计的控制器具有较好的实时性和较高的控制精确度.  相似文献   

5.
基于TS(Takagi-Sugeno)模糊模型,研究具有参数不确定性Chert混沌系统的鲁棒控制器设计。首先构建含有参数不确定性的TS模糊模型:然后利用并行分布补偿的方法,设计使模糊系统在平衡点附近渐近稳定的鲁棒模糊控制器。该设计通过解一组线性矩阵不等式(LMI)得到局部区域控制器,进而设计TS模糊系统的鲁棒控制器。该鲁棒模糊控制器的渐近稳定性条件更为宽松,能够降低控制器设计的保守性。最后的仿真结果表明所设计的鲁棒模糊控制器对参数不确定Chert混沌系统具有良好的控制效果。  相似文献   

6.
This paper presents a design method for robust model matching control of nonminimum‐phase discrete‐time systems. This scheme can robustly control the nominal model in the presence of unmodeled dynamics and can achieve the desired model matching simultaneously. Furthermore, the sufficient condition for stabilizing the nominal model in the presence of the unmodeled dynamics is derived and the existence of bounds for all signals is proved. Finally, computer simulation results are presented to illustrate the effectiveness of the proposed method. © 1999 Scripta Technica, Electr Eng Jpn, 128(2): 36–44, 1999  相似文献   

7.
In earlier papers, it has been reported that a fast and precise servo system, which has low sensitivity to parameter variation and disturbance, can be realized with simple structure by using a high‐order disturbance observer. However, no clear and simple design method satisfying specifications for robust stability, the influence of measurement noise, and relative stability (damping characteristics) for large parameter variation has been proposed. In this paper, we clarify the class of robust servo systems realized by adjusting the order of the disturbance observer and the control parameters. We apply this strategy to the design of a second delay system, such as a position servo system, and realize a high‐performance robust servo system using a high‐order disturbance observer. © 1999 Scripta Technica, Electr Eng Jpn, 128(1): 37–44, 1999  相似文献   

8.
导频辅助的信道估计方法是OFDM系统中应用最为广泛的一类信道估计方法,其中的2-D维纳滤波是最小均方误差意义下的最佳线性估计器,但是由于其计算量非常大,因而在实际中不能得到很好的应用。2×1-D的维纳滤波器利用信道相关函数的可分离性,对2-D维纳滤波器进行了简化,一定程度地降低了其复杂性,但仍然需要知道或估计信道的统计特性。文中介绍了一种基于非线性模型的信道估计方法,对其算法进行了仿真并与2×1-D维纳滤波的误比特率(BER)性能进行了比较。仿真结果表明,此方法能以较低的复杂性达到与2×1-D维纳滤波相近的性能,且无需对信道特性估计,是一种较实用的信道估计方法。  相似文献   

9.
为了克服安时积分法和开路电压法估计电池SOC的缺点,使用扩展卡尔曼滤波法将安时积分法与开路电压法结合起来。使用Thevenin等效电路电池模型作为扩展卡尔曼滤波法的模型基础,提出简化扩展卡尔曼滤波器过程噪声协方差和测量噪声协方差的方法,使电池SOC估计误差接近开路电压法的水平。最后,通过DST实验验证提出的电池SOC估计方法。  相似文献   

10.
This paper proposes an identification algorithm for time‐varying systems. We apply subspace method for estimation, since it is known to be useful when the input–output (I/O) data are observed by multi‐input multi‐output (MIMO) systems. Among many proposed techniques of subspace methods, we use MOESP (MIMO Output‐Error State Space model identification) in this paper, which assures arithmetic stability by RQ factorization and singular value decomposition (SVD). Generally, subspace methods can be applied after I/O data collection, so that we introduce updated steps of matrices for PI‐MOESP, which uses past inputs for instrumental variables. We propose a recursive update algorithm of PI‐MOESP, including estimation step of the system order, and consider some parameters inherent to the algorithm, namely, initial number of data, estimation step of the order, and forgetting factor. A numerical example shows the usefulness of the proposed method. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(2): 57–64, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20169  相似文献   

11.
研究了Box—Jenkins模型阶次与参数的同时估计问题.基于信息压缩阵的UD分解技术和广义增广最小二乘原理,提出Box-Jenkins模型阶次与参数同时估计的一种递推算法,减少了辨识计算量,改善数值稳定性,提高了辨识精度.仿真结果表明该算法的有效性。  相似文献   

12.
从适用于电动汽车锂离子电池荷电状态(SOC)估计的等效电路模型出发,对Rint、RC、Thevenin、PNGV和GNL等模型进行了归纳和总结,着重介绍了PNGV等效电路模型的基本原理、参数辨识过程及其研究现状。针对PNGV模型,进行模型电路的结构和参数辨识的优化,从而使电池模型在整个生命周期内都能真实且准确地反映出电池的实际属性,将会是今后该领域研究和应用的重点。  相似文献   

13.
This paper proposes and analyzes a new simple real‐time phase‐estimation method for single‐phase signals, which is based on a vector mapping theory of n‐dimensional to 2‐dimensional vectors. According to the analyses, the proposed mapping method can estimate instantly and properly the true phase of the signals that are contaminated by significant amplitude of noise and harmonics. The mapping method contains the conventional DFT method as a special case. In other words, it can be treated as a generalization of the DFT. Several simple realizations of the mapping method are also newly proposed as a single‐input and two‐output digital mapping filter in both nonrecursive and recursive forms. The recursive realization being able to decrease drastically computing load utilizes the normal form that is robust to finite word length effects. As an application of the proposed mapping method, inverter‐using power control system connected with a single‐phase grid is shown. All analytical results are verified by numerical experiments and the usefulness of the newly proposed mapping method is confirmed. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(1): 27–38, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20263  相似文献   

14.
基于图论理论的通用化操作票微机生成系统   总被引:1,自引:0,他引:1  
庄宗源 《广东电力》2001,14(4):54-58
介绍了一个基于Windows平台的新型可视化操作票自动生成系统,以图论为基础,提出了主接线图拓扑结构的邻接矩阵表示法和保护配置的关联矩阵表示法,使通用性成为可能。该系统具备良好通用性和用户可维护性,具有操作票模拟演示和模拟培训功能。  相似文献   

15.
The problem of decentralized robust tracking and model following is considered for a class of large‐scale interconnected systems with uncertainties. A class of linear decentralized state feedback controllers are proposed for robust tracking of dynamical signals in such a class of uncertain large‐scale systems. The proposed decentralized tracking controllers can guarantee that the tracking errors between each subsystem and local reference model are uniformly ultimately bounded. Moreover, we modify the linear controllers by introducing some nonlinear parts so that the tracking errors decrease asymptotically to zero in the presence of uncertain parameters and interconnection terms. Finally, an illustrative example is given to demonstrate the validity of our results. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(2): 48–58, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10101  相似文献   

16.
利用混沌优化算法确定河流水质模型参数   总被引:8,自引:1,他引:8  
应用混沌序列优化算法求解分析一维河流水团示踪试验数据 ,确定水质参数的函数优化问题。就算法控制参数对细搜索次数的影响进行了数值实验。结果表明 :( 1)该算法可以有效地应用 ;( 2 )过大的序列长度不能有效地缩短计算时间 ;( 3 )粗搜索次数对算法的收敛性影响不大 ;( 4 )水质参数的初始取值范围对算法收敛性基本没有影响  相似文献   

17.
电池荷电状态(SOC)的估算精度是影响新能源汽车性能的重要因素之一。针对电池参数动态变化影响SOC估算精度的问题,在确定二阶RC等效电路模型的基础上,采用渐衰记忆的递推最小二乘算法和扩展卡尔曼滤波算法对模型参数与SOC在线联合估算。经过实验与仿真验证,在模拟城市道路工况的放电条件下,与安时法和卡尔曼法相比,联合估算方法得到的SOC估算值与真实值的误差缩小到1.29%。该方法能够适应电池特性的动态变化,保证较高的SOC估算精度。  相似文献   

18.
彭勇 《广东电力》2006,19(7):4-8
提出了一种火电厂热力系统通用矩阵模型,该模型基于热力系统的组态结构矩阵,全面考虑了回热加热器换热效率以及各种辅助汽水等因素,以矩阵论为基础,对回热加热器的物质平衡和能量平衡关系进行了分析,通用性很强。该模型适用于不同类型或同类型、不同热力系统的大型火电机组的热经济性分析,为热力系统的实时监测、控制和优化提供了方便的工具。  相似文献   

19.
This paper presents and analyzes a new simple instant‐estimation method for time‐average quantities such as rms values of voltage and current, active and reactive powers, and power factor for single‐phase power with the fundamental component of constant or nearly constant frequency by measuring instantaneous values of voltage and current. According to the analyses, the method can instantly estimate time‐average values with accuracy of the fundamental frequency, and estimation accuracy of the power factor is about two times better than that of voltage, current, and powers. The instant‐estimation method is simple and can be easily applied to single‐phase power control systems that are expected to control instantly and continuously power factor on a single‐phase grid by inverter. Based on the proposed instant‐estimation method, two methods for such power control systems are also proposed and their usefulness is verified through simulations. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(2): 34–43, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20236  相似文献   

20.
This paper proposes two new “disturbance observers in the D‐module” for sensorless drive of synchronous motors including permanent‐magnet synchronous motors and synchronous reluctance motors. The disturbance filter for the observers can estimate speed‐varying rotor phase (in other words, rotor position) with zero phase lag. It is constructed by means of “the filter in the D‐module,” which has the following desired characteristics for variable sensorless drive: (1) it makes distinction between positive and negative frequencies of two‐phase signals; (2) it can allow processing of the signals based on frequency polarities; (3) it can also change dynamically its center frequency of bandpass filtering according to rotor speed estimates; (4) its passband and transition can be designed independently; and (5) it can be easily realized. The new disturbance observers also have a generality such that they contain the recently proposed disturbance observer as a special case. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(3): 63–70, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20602  相似文献   

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