本文選題：大型光伏電站 + 并網(wǎng)逆變器　； 參考：《重慶大學(xué)》2014年博士論文

【摘要】：在能源緊缺和環(huán)境污染日益嚴(yán)重的新形勢(shì)下，建設(shè)大型光伏電站是大規(guī)模利用太陽能的有效方式，也是優(yōu)化能源配置和緩解霧霾天氣的重要途徑。但大型光伏電站通常建立在遠(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。光伏電站存在并網(wǎng)電能質(zhì)量低、電網(wǎng)電壓波動(dòng)越限等問題，而且當(dāng)變壓器與長距離輸電線路等構(gòu)成的電網(wǎng)阻抗較大時(shí)或者裝機(jī)容量增加時(shí)，易引起光伏發(fā)電系統(tǒng)產(chǎn)生諧振，限制了光伏電站的規(guī)�；瘧�(yīng)用。為提高光伏電站的并網(wǎng)電能質(zhì)量，增強(qiáng)光伏電站并網(wǎng)穩(wěn)定性，論文圍繞光伏電站和電網(wǎng)之間的相互影響機(jī)理，以光伏電站中的并網(wǎng)逆變器為研究對(duì)象，從光伏電站的等效建模以及并網(wǎng)逆變器在非理想電網(wǎng)下的控制、無功調(diào)壓控制和并網(wǎng)穩(wěn)定性方面探討了并網(wǎng)逆變器面臨的技術(shù)難題，并提出了相應(yīng)的分析方法及解決方案。 論文首先以863課題“大型光伏電站并網(wǎng)關(guān)鍵技術(shù)研究”所依托的國電蒙電40MWp光伏發(fā)電項(xiàng)目為例，通過對(duì)光伏陣列、并網(wǎng)逆變器以及輸電網(wǎng)絡(luò)電路模型的分析，建立了光伏電站的等效電路模型，指出光伏電站和電網(wǎng)之間以及各并網(wǎng)逆變器之間相互影響的關(guān)鍵因素在于電網(wǎng)阻抗。在此基礎(chǔ)上，針對(duì)光伏電站并網(wǎng)逆變器LCL濾波器諧振和直流側(cè)電壓波動(dòng)等問題，研究了并網(wǎng)逆變器在正常電網(wǎng)下的電流環(huán)優(yōu)化方案，為并網(wǎng)逆變器后續(xù)問題的深入研究奠定了基礎(chǔ)。 實(shí)際上各并網(wǎng)逆變器的接入點(diǎn)電壓并不是理想的，為提高并網(wǎng)電能質(zhì)量，論文分別從電網(wǎng)畸變不平衡和電網(wǎng)基頻偏移角度進(jìn)行了分析。針對(duì)電網(wǎng)畸變不平衡，分析了傳統(tǒng)正序電流控制和有功恒定控制之間的矛盾，提出了并網(wǎng)逆變器在靜止坐標(biāo)系下的協(xié)調(diào)控制策略以及相應(yīng)的正負(fù)序基波分量提取算法。針對(duì)電網(wǎng)基頻偏移，分析了電流控制器諧振帶寬抑制能力不足的缺點(diǎn)，并給出了相應(yīng)的改進(jìn)方案。在上述基礎(chǔ)上，提出了并網(wǎng)逆變器在非理想電網(wǎng)下的控制策略，即在保證并網(wǎng)電能質(zhì)量前提下，通過調(diào)節(jié)電流控制指令中負(fù)序分量的權(quán)重，實(shí)現(xiàn)并網(wǎng)電流幅值不平衡和瞬時(shí)有功波動(dòng)之間的協(xié)調(diào)控制。仿真與實(shí)驗(yàn)結(jié)果也驗(yàn)證了所提控制策略的可行性和有效性。 針對(duì)光伏電站電網(wǎng)電壓波動(dòng)越限的無功調(diào)壓問題，論文從電網(wǎng)電壓穩(wěn)定性角度出發(fā)，對(duì)光伏電站有功輸出變化對(duì)并網(wǎng)電壓的影響進(jìn)行了量化分析。此外，歸納總結(jié)了并網(wǎng)逆變器在不同控制方式下的無功容量及其無功補(bǔ)償局限性，提出了無功補(bǔ)償裝置為主、并網(wǎng)逆變器為輔的無功輸出模式。在此基礎(chǔ)上，依據(jù)電力系統(tǒng)無功與電壓控制的基本思想，提出了適用于光伏電站的并網(wǎng)逆變器無功調(diào)壓控制策略，并對(duì)具體實(shí)現(xiàn)方式、無功分配方案、光伏發(fā)電單元無功優(yōu)化等關(guān)鍵問題進(jìn)行了闡述。算例仿真也驗(yàn)證了所提無功調(diào)壓控制策略的可行性和有效性。 最后，針對(duì)光伏電站裝機(jī)容量增加時(shí)或者電網(wǎng)阻抗較大時(shí)光伏發(fā)電系統(tǒng)的穩(wěn)定性問題，論文將電網(wǎng)阻抗因素考慮到光伏電站并網(wǎng)逆變器電流控制中，通過對(duì)電網(wǎng)阻抗在各并網(wǎng)逆變器之間耦合效應(yīng)的分析，建立了考慮電網(wǎng)阻抗影響的光伏電站等效電路模型。在此基礎(chǔ)上，利用傳統(tǒng)的頻域分析法，，從系統(tǒng)阻尼和開環(huán)傳遞函數(shù)兩個(gè)角度，分析了電網(wǎng)阻抗對(duì)并網(wǎng)逆變器電流控制的影響，理論分析表明：等效電抗的影響要遠(yuǎn)大于等效電阻，等效電阻的增加會(huì)降低系統(tǒng)的穩(wěn)態(tài)性能，而等效電抗的增加會(huì)嚴(yán)重減小系統(tǒng)的截止頻率和穩(wěn)定裕度，進(jìn)而降低系統(tǒng)的動(dòng)態(tài)性能甚至導(dǎo)致不穩(wěn)定。對(duì)此，論文分別從光伏電站規(guī)劃和并網(wǎng)逆變器電流控制角度給出了初步的解決思路。算例仿真和相關(guān)實(shí)驗(yàn)也驗(yàn)證了上述理論分析的正確性。
[Abstract]:Under the new situation that the energy shortage and environmental pollution are increasingly serious, the construction of large photovoltaic power stations is an effective way to utilize the solar energy in large scale. It is also an important way to optimize the energy allocation and alleviate the haze weather. However, the large photovoltaic power stations are usually built in the desert areas which are far from the load center, the light resources are rich, and the photovoltaic power generation system passes through. The long distance transmission line is connected with the load. There are some problems in the photovoltaic power station, such as the low quality of the grid connected power and the limit of the voltage fluctuation of the power grid. And when the transformer and the long distance transmission line are more impedance and the installed capacity increases, it will easily cause the resonance of the photovoltaic power generation system, which restricts the scale application of the photovoltaic power station. In order to improve the grid connected power quality of the photovoltaic power station and enhance the stability of the grid connected photovoltaic power station, the paper focuses on the interaction mechanism between the photovoltaic power station and the power grid, taking the grid connected inverter in the photovoltaic power station as the research object, from the equivalent modeling of the photovoltaic power station, the control of the grid connected inverter under the non rational power grid, the reactive voltage control control and the grid connected stability. The technical difficulties faced by grid connected inverters are discussed qualitatively, and corresponding analysis methods and solutions are proposed.
The paper first takes the 863 subject "the key technology of large photovoltaic power station to be connected to the grid" as an example. Through the analysis of the photovoltaic array, the grid connected inverter and the transmission network circuit model, the equivalent circuit model of the photovoltaic power station is set up, and the inverse of the photovoltaic power station and the grid and the converse of each grid are pointed out. The key factor of the interaction between the transformers lies in the impedance of the power grid. On this basis, the current loop optimization scheme of the grid connected inverter under the normal power grid is studied for the problems of the LCL filter resonance and the DC side voltage fluctuation of the grid connected inverters of the PV power station.
In fact, the access point voltage of the grid connected inverters is not ideal. In order to improve the quality of grid connected power, the paper analyzes the unbalanced power grid distortion and the basic frequency offset of the power grid respectively. In view of the unbalanced grid distortion, the contradiction between the traditional positive sequence current control and the active power constant control is analyzed, and the grid connected inverter is put forward in the static state. The coordination control strategy under the check coordinate system and the corresponding positive negative sequence fundamental wave component extraction algorithm. In view of the basic frequency offset of the power grid, the shortcomings of the current controller's lack of resonant bandwidth suppression ability are analyzed, and the corresponding improvement scheme is given. On the premise of grid connected power quality, by adjusting the weight of the negative sequence component in the current control instruction, the coordinated control between the unbalanced current amplitude and the instantaneous active power fluctuation is realized. The simulation and experimental results also verify the feasibility and effectiveness of the proposed control strategy.
In view of the reactive voltage regulation of the voltage fluctuation limit of the power grid of the photovoltaic power station, this paper quantifies the influence of the active output change of the photovoltaic power station on the grid voltage from the angle of the voltage stability of the power grid, and summarizes the reactive power capacity and the limitation of the reactive power compensation of the grid connected inverter under different control modes. On the basis of the basic thought of power system reactive power and voltage control, the reactive power control strategy for grid connected inverters suitable for photovoltaic power stations is proposed on this basis, and the key questions of specific realization mode, reactive distribution scheme and reactive power optimization of photovoltaic power unit are also discussed. The simulation results also verify the feasibility and effectiveness of the proposed reactive power voltage regulation strategy.
Finally, in view of the increase of the capacity of the photovoltaic power plant, or the stability of the power system with a large impedance time, the paper takes the impedance factor of the power grid into consideration in the current control of the grid connected inverters of the photovoltaic power station. Through the analysis of the coupling effect between the grid impedance and the grid inverters, the light of the grid impedance is established. On the basis of the equivalent circuit model of the volt power station, the influence of the electric network impedance on the current control of the grid connected inverter is analyzed from two angles of the system damping and the open loop transfer function. The theoretical analysis shows that the effect of the equivalent reactance is far greater than the equivalent resistance, and the increase of the equivalent resistance will reduce the steady state of the system. The performance, and the increase of the equivalent reactance will seriously reduce the cut-off frequency and stability margin of the system, and then reduce the dynamic performance of the system and even lead to instability. This paper gives a preliminary solution to the current control of the PV power station planning and the grid connected inverter. The correctness of the analysis.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類號(hào)】：TM464

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 汪海寧,蘇建徽,張國榮,茆美琴,丁明;光伏并網(wǎng)發(fā)電及無功補(bǔ)償?shù)慕y(tǒng)一控制[J];電工技術(shù)學(xué)報(bào);2005年09期

2 吳理博;趙爭鳴;劉建政;王健;袁立強(qiáng);;具有無功補(bǔ)償功能的單級(jí)式三相光伏并網(wǎng)系統(tǒng)[J];電工技術(shù)學(xué)報(bào);2006年01期

3 周德佳;趙爭鳴;袁立強(qiáng);馮博;;300kW光伏并網(wǎng)系統(tǒng)優(yōu)化控制與穩(wěn)定性分析[J];電工技術(shù)學(xué)報(bào);2008年11期

4 郭小強(qiáng);鄔偉揚(yáng);顧和榮;王立喬;趙清林;;并網(wǎng)逆變器LCL接口直接輸出電流控制建模及穩(wěn)定性分析[J];電工技術(shù)學(xué)報(bào);2010年03期

5 劉飛;查曉明;段善旭;;三相并網(wǎng)逆變器LCL濾波器的參數(shù)設(shè)計(jì)與研究[J];電工技術(shù)學(xué)報(bào);2010年03期

6 卞海紅;徐青山;高山;雪田和人;一柳勝宏;;考慮隨機(jī)陰影影響的光伏陣列失配運(yùn)行特性[J];電工技術(shù)學(xué)報(bào);2010年06期

7 章瑋;王宏勝;任遠(yuǎn);胡家兵;賀益康;;不對(duì)稱電網(wǎng)電壓條件下三相并網(wǎng)型逆變器的控制[J];電工技術(shù)學(xué)報(bào);2010年12期

8 耿攀;吳衛(wèi)民;葉銀忠;劉以建;;基于重復(fù)控制的單相分時(shí)復(fù)合級(jí)聯(lián)光伏逆變器控制[J];電工技術(shù)學(xué)報(bào);2011年03期

9 楊勇;趙方平;阮毅;趙春江;;三相并網(wǎng)逆變器模型電流預(yù)測控制技術(shù)[J];電工技術(shù)學(xué)報(bào);2011年06期

10 尚磊;孫丹;胡家兵;賀益康;;三相電壓型并網(wǎng)逆變器預(yù)測直接功率控制[J];電工技術(shù)學(xué)報(bào);2011年07期

相關(guān)博士學(xué)位論文 前3條

1 鄭征;雙PWM變頻器及其協(xié)調(diào)控制技術(shù)研究[D];中國礦業(yè)大學(xué)（北京）;2011年

2 劉飛;三相并網(wǎng)光伏發(fā)電系統(tǒng)的運(yùn)行控制策略[D];華中科技大學(xué);2008年

3 殷進(jìn)軍;LCL濾波并網(wǎng)逆變器的數(shù)字單環(huán)控制技術(shù)研究[D];華中科技大學(xué);2012年

本文編號(hào)：2000935