本文選題：大型光伏并網(wǎng)系統(tǒng) + 電網(wǎng)阻抗�。� 參考：《重慶大學(xué)》2014年碩士論文

【摘要】：大型光伏電站通常建在遠(yuǎn)離負(fù)荷中心、光照資源豐富的荒漠地區(qū)，光伏發(fā)電系統(tǒng)經(jīng)過長距離輸電線路與負(fù)荷連接，當(dāng)變壓器與長距離輸電線路等構(gòu)成電網(wǎng)阻抗較大時(shí)，易引起大型光伏并網(wǎng)系統(tǒng)產(chǎn)生諧振現(xiàn)象，造成系統(tǒng)出現(xiàn)諧振過電壓、過電流等問題，威脅著系統(tǒng)的安全穩(wěn)定運(yùn)行。因此，本文以大型光伏并網(wǎng)系統(tǒng)為研究對象，以提高大型光伏電站的系統(tǒng)穩(wěn)定性和并網(wǎng)電能質(zhì)量為研究目標(biāo)，探索大型光伏電站與電網(wǎng)之間的諧振機(jī)理。在建立大型光伏并網(wǎng)系統(tǒng)數(shù)學(xué)模型的基礎(chǔ)上，，探討光伏電站容量、電網(wǎng)阻抗等參數(shù)對系統(tǒng)穩(wěn)定運(yùn)行的影響，提出大型光伏并網(wǎng)系統(tǒng)的穩(wěn)定性判定方法，研究抑制諧振引發(fā)系統(tǒng)不穩(wěn)定問題的逆變器控制策略，為大型光伏電站的發(fā)展及其推廣應(yīng)用奠定理論基礎(chǔ)。論文研究內(nèi)容主要包括： 1）建立大型光伏并網(wǎng)系統(tǒng)等效電路模型：對于大型光伏并網(wǎng)系統(tǒng)建模主要可以劃分為輸電網(wǎng)絡(luò)建模和逆變器建模兩部分，分別建立輸電網(wǎng)絡(luò)和大型光伏電站兩個(gè)子系統(tǒng)的等效模型后獲得大型光伏并網(wǎng)系統(tǒng)等效模型。對于升壓變壓器以及長距離輸電線路構(gòu)成的輸電網(wǎng)絡(luò)建模，通常采用線性無源二端網(wǎng)絡(luò)表示。然后，采用降階建模法將直流側(cè)電壓假定為常數(shù)，忽略逆變器直流側(cè)電容后建立并網(wǎng)光伏逆變器的等效電路模型。最后，結(jié)合由無源二端網(wǎng)絡(luò)表示的輸電網(wǎng)絡(luò)等效模型以及整個(gè)大型光伏電站的等效電路模型，形成大型光伏并網(wǎng)系統(tǒng)的等效電路模型。 2）大型光伏并網(wǎng)系統(tǒng)的諧振現(xiàn)象研究：在建立大型光伏并網(wǎng)系統(tǒng)等效電路模型基礎(chǔ)上，本文主要針對大型光伏并網(wǎng)系統(tǒng)中的諧振現(xiàn)象進(jìn)行深入研究，在考慮分裂變壓器等效電感及電網(wǎng)阻抗情況下，深入分析大型光伏電站與電網(wǎng)之間的諧振交互式影響，探討系統(tǒng)諧振引發(fā)的不穩(wěn)定現(xiàn)象。本文首先分析大型光伏并網(wǎng)系統(tǒng)諧振問題對系統(tǒng)諧波含量的影響，推導(dǎo)大型光伏并網(wǎng)系統(tǒng)阻抗穩(wěn)定性判據(jù)，然后采用根軌跡分析了各參數(shù)對大型光伏并網(wǎng)系統(tǒng)的穩(wěn)定性影響。 3）光伏并網(wǎng)系統(tǒng)諧振抑制策略研究：由于電網(wǎng)阻抗會(huì)導(dǎo)致光伏并網(wǎng)系統(tǒng)中光伏電站與電網(wǎng)之間的諧振交互式影響，嚴(yán)重時(shí)甚至造成系統(tǒng)出現(xiàn)不穩(wěn)定現(xiàn)象，導(dǎo)致系統(tǒng)不能正常工作，因此如何對光伏并網(wǎng)系統(tǒng)中的諧振現(xiàn)象進(jìn)行有效抑制是目前國內(nèi)外專家的研究熱點(diǎn)。本文從簡單的單臺(tái)光伏逆變器并網(wǎng)系統(tǒng)的諧振現(xiàn)象分析出發(fā)，采用基于狀態(tài)反饋的極點(diǎn)配置策略對系統(tǒng)中的諧振現(xiàn)象進(jìn)行了有效抑制，并通過仿真驗(yàn)證了極點(diǎn)配置策略對諧振抑制的有效性。
[Abstract]:Large photovoltaic power plants are usually built in desert areas far from load center and rich in light resources. Photovoltaic power generation systems are connected to loads through long distance transmission lines. When transformers and long distance transmission lines make up the power grid impedance is large. It is easy to cause resonance phenomenon in large-scale photovoltaic grid-connected system, resulting in resonance overvoltage, over-current and other problems, which threaten the safe and stable operation of the system. Therefore, this paper takes the large-scale photovoltaic grid-connected system as the research object, with the aim of improving the system stability and grid-connected power quality of the large-scale photovoltaic power station, and explores the resonance mechanism between the large-scale photovoltaic power station and the grid. Based on the mathematical model of large-scale photovoltaic grid-connected system, this paper discusses the influence of the parameters such as the capacity of photovoltaic power station and the impedance of power grid on the stable operation of the system, and puts forward a method for judging the stability of large-scale photovoltaic grid-connected system. The inverter control strategy to suppress the instability of the resonant induced system is studied, which lays a theoretical foundation for the development and application of large photovoltaic power plants. The main contents of this paper are as follows: 1) establishing equivalent circuit model of large-scale photovoltaic grid-connected system: the modeling of large-scale photovoltaic grid-connected system can be divided into two parts: transmission network modeling and inverter modeling. The equivalent models of two subsystems of transmission network and large photovoltaic power station are established, and the equivalent model of large-scale photovoltaic grid-connected system is obtained. The linear passive two-terminal network is usually used to model the transmission network composed of booster transformers and long-distance transmission lines. Then, the DC side voltage is assumed to be constant by using the reduced order modeling method, and the equivalent circuit model of grid-connected photovoltaic inverter is established by ignoring the DC side capacitance of the inverter. Finally, the equivalent model of transmission network represented by passive two-terminal network and the equivalent circuit model of the whole large photovoltaic power station are combined. Forming equivalent circuit model of large-scale photovoltaic grid-connected system. 2) Resonance phenomenon of large-scale photovoltaic grid-connected system: on the basis of establishing equivalent circuit model of large-scale photovoltaic grid-connected system, In this paper, the resonance phenomenon in large-scale photovoltaic grid-connected system is studied deeply. Considering the equivalent inductance and grid impedance of split transformer, the resonant interaction between large-scale photovoltaic power station and power grid is deeply analyzed. The instability caused by system resonance is discussed. In this paper, the influence of resonance problem on harmonic content of large-scale photovoltaic grid-connected system is analyzed, and the impedance stability criterion of large-scale photovoltaic grid-connected system is derived. Then the influence of various parameters on the stability of large-scale grid-connected photovoltaic system is analyzed by root locus. 3) Resonance suppression strategy of grid-connected photovoltaic system: because of the impedance of the grid, the photovoltaic power station and the photovoltaic power station in the grid-connected system The interactive effects of resonance between power grids, When the system is seriously unstable, the system can not work properly. Therefore, how to effectively suppress the resonance phenomenon in photovoltaic grid-connected system is a hot research topic at home and abroad. Based on the simple resonance analysis of a grid-connected system with a single photovoltaic inverter, the pole placement strategy based on state feedback is used to effectively suppress the resonance phenomenon in the system. The effectiveness of pole placement strategy for resonance suppression is verified by simulation.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TM615

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 趙爭鳴;雷一;賀凡波;魯宗相;田琦;;大容量并網(wǎng)光伏電站技術(shù)綜述[J];電力系統(tǒng)自動(dòng)化;2011年12期

2 鄭旭,裴志宏,孫海順,王少榮;可控串補(bǔ)動(dòng)模裝置研制及阻抗特性研究[J];電力自動(dòng)化設(shè)備;2005年05期

3 周任軍;黃靈資;王靚;楊雨薇;范文帥;劉陽升;;基于風(fēng)險(xiǎn)和條件風(fēng)險(xiǎn)方法的光伏電站并網(wǎng)極限容量計(jì)算[J];電力自動(dòng)化設(shè)備;2012年06期

4 艾欣;韓曉男;孫英云;;大型光伏電站并網(wǎng)特性及其低碳運(yùn)行與控制技術(shù)[J];電網(wǎng)技術(shù);2013年01期

5 周林;馮玉;郭珂;劉強(qiáng);賈芳成;黃勇;;單相光伏并網(wǎng)逆變器建模與控制技術(shù)研究[J];太陽能學(xué)報(bào);2012年03期

6 佟強(qiáng);張東來;徐殿國;;分布式電源系統(tǒng)中變換器的輸出阻抗與穩(wěn)定性分析[J];中國電機(jī)工程學(xué)報(bào);2011年12期

7 郭小強(qiáng);鄔偉揚(yáng);漆漢宏;;電網(wǎng)電壓畸變不平衡情況下三相光伏并網(wǎng)逆變器控制策略[J];中國電機(jī)工程學(xué)報(bào);2013年03期

8 許德志;汪飛;毛華龍;阮毅;張巍;;多并網(wǎng)逆變器與電網(wǎng)的諧波交互建模與分析[J];中國電機(jī)工程學(xué)報(bào);2013年12期

9 曾正;趙榮祥;湯勝清;楊歡;呂志鵬;;可再生能源分散接入用先進(jìn)并網(wǎng)逆變器研究綜述[J];中國電機(jī)工程學(xué)報(bào);2013年24期

10 謝寧;羅安;馬伏軍;徐欣慰;呂志鵬;帥智康;;大型光伏電站與電網(wǎng)諧波交互影響[J];中國電機(jī)工程學(xué)報(bào);2013年34期

相關(guān)博士學(xué)位論文 前1條

1 袁建華;分布式光伏發(fā)電微電網(wǎng)供能系統(tǒng)研究[D];山東大學(xué);2011年

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