互联电网低频振荡能量解析的支路模式势能法
发布时间：2018-12-11 17:11
【摘要】：低频振荡问题一直是互联电网的重大威胁之一,特别是新能源接入后,其出力不确定性使得电力系统低频振荡问题变得更加复杂,所以如何合理的分析及控制电网低频振荡就变得极为重要。虽然这一领域的研究已取得了长足的进步,但揭示网络局部对电力系统低频振荡影响的物理本质仍是尚未解决的难题。本文将能量函数与小干扰模式概念相结合,从能量分层解析角度开展基于网络局部信息的低频振荡定量分析方法研究,并探索该方法在系统振荡度评价,主振荡路径识别和阻尼控制中的应用,揭示低频振荡的作用机理,为有效识别网络中的薄弱环节、实现振荡度评估,解决低频振荡的分析与抑制提供切实可行的新思路。所以综上所述,本文完成的主要工作有以下几方面:(1)建立基于网络的模式势能函数,计算不同模式下网络中的任意支路的势能,研究模式势能的构成,为基于网络局部信息的小干扰稳定性的研究创造条件;(2)研究系统模式势能在网络中各支路分布的变化特性,阐述分布于网络中的模式势能与发电机动能的相互转换关系,分析支路模式势能的分布与系统小干扰稳定性的定性关系,研究模式势能在网络中分布特点及其与系统模式振荡中心的对应关系,从网络模式势能的角度解释了系统的低频振荡机理;(3)在进一步分析模式势能变化特点的基础上,建立基于支路信息的系统低频振荡振荡度判据,提出仅依赖于网络信息的低频振荡分析方法——支路模式势能分析法。借助该方法可定量分析系统振荡度,评价网络中支路以及割集对系统小干扰稳定性的影响,发现网络中的薄弱环节。提出模式势能熵阻尼定量评价指标,从网络能量角度对电力系统低频振荡进行分层能量解析,评价系统不同模式的阻尼情况;(4)以模式势能分析法为基础,构建基于广域量测的支路模式势能,对互联电网低频振荡进行模式能量解析,可得到系统低频振荡的振荡交互情况,同时通过所建立指标可快速判别功率振荡度及各发电机参与度,用以判别系统主导振荡路径;(5)构建含风机互联电网的模式动能、模式势能和总模式能量函数,进而利用模式总能量耗散原理结合滑模变结构和鲁棒控制理论设计一种新颖的能量滑模鲁棒控制策略(sliding mode control-H∞,SMCH)用于设计广域阻尼控制器以便改善双馈风机阻尼控制能力,并分析了模式势能法在电力系统广域阻尼控制中的应用潜力。
[Abstract]:The problem of low frequency oscillation has been one of the major threats to the interconnected power network, especially after the new energy access, the uncertainty of its output makes the problem of low frequency oscillation of power system more complex. Therefore, how to reasonably analyze and control the low-frequency oscillation becomes extremely important. Although great progress has been made in this field, it is still an unsolved problem to reveal the physical nature of the influence of local network on low frequency oscillation in power system. In this paper, the energy function is combined with the concept of small interference mode, and the quantitative analysis method of low frequency oscillation based on the local information of the network is studied from the view of energy stratification analysis, and the evaluation of the oscillation degree of the system by this method is explored. The application of main oscillation path identification and damping control reveals the mechanism of low frequency oscillation, which provides a new practical way to identify the weak links in the network effectively, to realize the evaluation of oscillation degree and to solve the analysis and suppression of low frequency oscillation. To sum up, the main work of this paper is as follows: (1) to establish the model potential energy function based on the network, calculate the potential energy of any branch of the network in different modes, and study the structure of the mode potential energy. It creates conditions for the study of the stability of small interference based on local information of the network. (2) the variation characteristics of the distribution of system mode potential energy in each branch of the network are studied, and the relationship between the mode potential energy distributed in the network and the kinetic energy of the generator is discussed. The qualitative relationship between the distribution of branch mode potential energy and the stability of the system with small disturbance is analyzed. The distribution characteristics of the potential energy in the network and the corresponding relationship between the distribution of the potential energy and the oscillation center of the system mode are studied. The low frequency oscillation mechanism of the system is explained from the point of view of the network mode potential energy. (3) on the basis of further analyzing the characteristics of mode potential energy variation, the system low-frequency oscillation degree criterion based on branch information is established, and a low-frequency oscillation analysis method based on network information is proposed, which is called branch-mode potential energy analysis method. With this method, the system oscillation degree can be quantitatively analyzed, and the influence of branch and cut set on the stability of the system with small disturbance can be evaluated, and the weak links in the network can be found. The quantitative evaluation index of mode potential energy entropy damping is put forward, and the hierarchical energy analysis of low frequency oscillation in power system is carried out from the view of network energy to evaluate the damping of different modes of power system. (4) based on the method of mode potential energy analysis, the branch mode potential energy based on wide area measurement is constructed, and the mode energy analysis of low frequency oscillation of interconnected power network is carried out, and the oscillation interaction of low frequency oscillation of the system can be obtained. At the same time, the power oscillation degree and the participation degree of each generator can be quickly distinguished by the established index, which can be used to judge the dominant oscillation path of the system. (5) the model kinetic energy, mode potential energy and total mode energy function of interconnected power grid with fan are constructed. Then a novel energy sliding mode robust control strategy, (sliding mode control-H 鈭，
本文编号：2372921
[Abstract]:The problem of low frequency oscillation has been one of the major threats to the interconnected power network, especially after the new energy access, the uncertainty of its output makes the problem of low frequency oscillation of power system more complex. Therefore, how to reasonably analyze and control the low-frequency oscillation becomes extremely important. Although great progress has been made in this field, it is still an unsolved problem to reveal the physical nature of the influence of local network on low frequency oscillation in power system. In this paper, the energy function is combined with the concept of small interference mode, and the quantitative analysis method of low frequency oscillation based on the local information of the network is studied from the view of energy stratification analysis, and the evaluation of the oscillation degree of the system by this method is explored. The application of main oscillation path identification and damping control reveals the mechanism of low frequency oscillation, which provides a new practical way to identify the weak links in the network effectively, to realize the evaluation of oscillation degree and to solve the analysis and suppression of low frequency oscillation. To sum up, the main work of this paper is as follows: (1) to establish the model potential energy function based on the network, calculate the potential energy of any branch of the network in different modes, and study the structure of the mode potential energy. It creates conditions for the study of the stability of small interference based on local information of the network. (2) the variation characteristics of the distribution of system mode potential energy in each branch of the network are studied, and the relationship between the mode potential energy distributed in the network and the kinetic energy of the generator is discussed. The qualitative relationship between the distribution of branch mode potential energy and the stability of the system with small disturbance is analyzed. The distribution characteristics of the potential energy in the network and the corresponding relationship between the distribution of the potential energy and the oscillation center of the system mode are studied. The low frequency oscillation mechanism of the system is explained from the point of view of the network mode potential energy. (3) on the basis of further analyzing the characteristics of mode potential energy variation, the system low-frequency oscillation degree criterion based on branch information is established, and a low-frequency oscillation analysis method based on network information is proposed, which is called branch-mode potential energy analysis method. With this method, the system oscillation degree can be quantitatively analyzed, and the influence of branch and cut set on the stability of the system with small disturbance can be evaluated, and the weak links in the network can be found. The quantitative evaluation index of mode potential energy entropy damping is put forward, and the hierarchical energy analysis of low frequency oscillation in power system is carried out from the view of network energy to evaluate the damping of different modes of power system. (4) based on the method of mode potential energy analysis, the branch mode potential energy based on wide area measurement is constructed, and the mode energy analysis of low frequency oscillation of interconnected power network is carried out, and the oscillation interaction of low frequency oscillation of the system can be obtained. At the same time, the power oscillation degree and the participation degree of each generator can be quickly distinguished by the established index, which can be used to judge the dominant oscillation path of the system. (5) the model kinetic energy, mode potential energy and total mode energy function of interconnected power grid with fan are constructed. Then a novel energy sliding mode robust control strategy, (sliding mode control-H 鈭，
本文编号：2372921
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