【摘要】：低頻振蕩問(wèn)題一直是互聯(lián)電網(wǎng)的重大威脅之一,特別是新能源接入后,其出力不確定性使得電力系統(tǒng)低頻振蕩問(wèn)題變得更加復(fù)雜,所以如何合理的分析及控制電網(wǎng)低頻振蕩就變得極為重要。雖然這一領(lǐng)域的研究已取得了長(zhǎng)足的進(jìn)步,但揭示網(wǎng)絡(luò)局部對(duì)電力系統(tǒng)低頻振蕩影響的物理本質(zhì)仍是尚未解決的難題。本文將能量函數(shù)與小干擾模式概念相結(jié)合,從能量分層解析角度開展基于網(wǎng)絡(luò)局部信息的低頻振蕩定量分析方法研究,并探索該方法在系統(tǒng)振蕩度評(píng)價(jià),主振蕩路徑識(shí)別和阻尼控制中的應(yīng)用,揭示低頻振蕩的作用機(jī)理,為有效識(shí)別網(wǎng)絡(luò)中的薄弱環(huán)節(jié)、實(shí)現(xiàn)振蕩度評(píng)估,解決低頻振蕩的分析與抑制提供切實(shí)可行的新思路。所以綜上所述,本文完成的主要工作有以下幾方面:(1)建立基于網(wǎng)絡(luò)的模式勢(shì)能函數(shù),計(jì)算不同模式下網(wǎng)絡(luò)中的任意支路的勢(shì)能,研究模式勢(shì)能的構(gòu)成,為基于網(wǎng)絡(luò)局部信息的小干擾穩(wěn)定性的研究創(chuàng)造條件;(2)研究系統(tǒng)模式勢(shì)能在網(wǎng)絡(luò)中各支路分布的變化特性,闡述分布于網(wǎng)絡(luò)中的模式勢(shì)能與發(fā)電機(jī)動(dòng)能的相互轉(zhuǎn)換關(guān)系,分析支路模式勢(shì)能的分布與系統(tǒng)小干擾穩(wěn)定性的定性關(guān)系,研究模式勢(shì)能在網(wǎng)絡(luò)中分布特點(diǎn)及其與系統(tǒng)模式振蕩中心的對(duì)應(yīng)關(guān)系,從網(wǎng)絡(luò)模式勢(shì)能的角度解釋了系統(tǒng)的低頻振蕩機(jī)理;(3)在進(jìn)一步分析模式勢(shì)能變化特點(diǎn)的基礎(chǔ)上,建立基于支路信息的系統(tǒng)低頻振蕩振蕩度判據(jù),提出僅依賴于網(wǎng)絡(luò)信息的低頻振蕩分析方法——支路模式勢(shì)能分析法。借助該方法可定量分析系統(tǒng)振蕩度,評(píng)價(jià)網(wǎng)絡(luò)中支路以及割集對(duì)系統(tǒng)小干擾穩(wěn)定性的影響,發(fā)現(xiàn)網(wǎng)絡(luò)中的薄弱環(huán)節(jié)。提出模式勢(shì)能熵阻尼定量評(píng)價(jià)指標(biāo),從網(wǎng)絡(luò)能量角度對(duì)電力系統(tǒng)低頻振蕩進(jìn)行分層能量解析,評(píng)價(jià)系統(tǒng)不同模式的阻尼情況;(4)以模式勢(shì)能分析法為基礎(chǔ),構(gòu)建基于廣域量測(cè)的支路模式勢(shì)能,對(duì)互聯(lián)電網(wǎng)低頻振蕩進(jìn)行模式能量解析,可得到系統(tǒng)低頻振蕩的振蕩交互情況,同時(shí)通過(guò)所建立指標(biāo)可快速判別功率振蕩度及各發(fā)電機(jī)參與度,用以判別系統(tǒng)主導(dǎo)振蕩路徑;(5)構(gòu)建含風(fēng)機(jī)互聯(lián)電網(wǎng)的模式動(dòng)能、模式勢(shì)能和總模式能量函數(shù),進(jìn)而利用模式總能量耗散原理結(jié)合滑模變結(jié)構(gòu)和魯棒控制理論設(shè)計(jì)一種新穎的能量滑模魯棒控制策略(sliding mode control-H∞,SMCH)用于設(shè)計(jì)廣域阻尼控制器以便改善雙饋風(fēng)機(jī)阻尼控制能力,并分析了模式勢(shì)能法在電力系統(tǒng)廣域阻尼控制中的應(yīng)用潛力。
[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，

本文編號(hào)：2372921