本文關鍵詞：基于三電平DC-DC變換器的風儲雙極性直流微電網(wǎng)運行控制策略研究　出處：《太原理工大學》2017年碩士論文　論文類型：學位論文

  更多相關文章： 雙極性直流微電網(wǎng) 三電平DC-DC變換器 充放電分離 電壓分區(qū)間控制 中點電位平衡

【摘要】：直流微電網(wǎng)作為新的能源結網(wǎng)形式,集成風力、光伏等新能源發(fā)電單元、儲能單元及本地負荷,實現(xiàn)可再生能源的高效利用,成為當前國內外研究熱點。目前直流微電網(wǎng)主要采用單極性結構,系統(tǒng)的運行效率較低。本文研究了基于三電平DC-DC變換器接入的雙極性直流微電網(wǎng)結構,該結構減小了母線對地電壓,提高了系統(tǒng)運行效率,且可滿足不同變換器和負荷對各電壓等級的要求,并基于此結構提出了相應的運行控制策略,主要研究內容包括:第一,詳細研究了雙極性直流微電網(wǎng)中三電平變換器的拓撲結構和工作原理,根據(jù)能量雙向流動特性將其分為三電平Boost變換器和三電平Buck變換器,并分析其工作狀態(tài)與輸入輸出關系。研究了風電單元中的三電平Boost變換器,同時建立該變換器的狀態(tài)空間數(shù)學模型。第二,重點研究了基于三電平Boost變換器的風電單元控制策略。建立了風電單元中各部分的模型,分析了風電機組在不同風速下的運行特性。在此基礎上,提出風能利用系數(shù)恒定區(qū)域的最大功率跟蹤控制(maximum power point tracking,MPPT)與高風速區(qū)域的恒轉速、恒功率控制策略。根據(jù)三電平Boost變換器輸出特性,設計了中點電位平衡控制以保證分裂電容電壓平衡。最后通過Matlab/Simulink仿真驗證了風電單元策略的有效性。該控制策略保證了風機在各個風速區(qū)域內穩(wěn)定運行,實現(xiàn)了區(qū)域間平滑切換,提高了風能的利用效率。第三,著重研究了基于三電平雙向DC-DC變換器的儲能單元控制策略。分析了超級電容器的工作原理和等效電路模型,建立了電壓下垂特性關系。根據(jù)直流母線電壓波動范圍,將超級電容器的運行分成不動作、下垂控制、恒流充放電三個階段,并提出一種充放電模式分離的控制策略。最后通過Matlab/Simulink仿真驗證了儲能單元控制策略的合理性。該控制策略在充電模式或放電模式時只需兩個開關管導通,降低了控制的復雜性。第四,提出了風儲雙極性直流微電網(wǎng)母線電壓分區(qū)間運行控制策略。分析了風儲雙極性直流微電網(wǎng)結構和功率平衡關系,并根據(jù)微電網(wǎng)不同狀態(tài)將母線電壓分成四個運行區(qū)間。通過風電單元的風電特性控制與基于下垂特性的限功率控制、儲能單元的充放電分離控制配合負荷單元的減載控制,實現(xiàn)了各狀態(tài)的穩(wěn)定運行與各區(qū)間的平滑切換。第五,搭建了含風電單元、超級電容儲能裝置和直流負荷的雙極性直流微電網(wǎng)實驗平臺,通過實驗驗證了控制策略在不同母線電壓下運行與不同狀態(tài)間切換的表現(xiàn)。結果表明,母線電壓分區(qū)間運行控制策略可以調節(jié)母線電壓和平衡系統(tǒng)功率,從而確保了風儲雙極性直流微電網(wǎng)穩(wěn)定運行。
[Abstract]:DC microgrid as a new form of energy grid integration of wind photovoltaic and other new energy generation units energy storage units and local load to achieve the efficient use of renewable energy. At present, DC microgrid mainly adopts unipolar structure. The structure of bipolar DC microgrid based on three-level DC-DC converter is studied in this paper, which reduces the bus voltage to the ground and improves the efficiency of the system. And it can meet the requirements of different converter and load on each voltage level. Based on this structure, the corresponding operation control strategy is proposed. The main research contents are as follows: first. The topology and working principle of three-level converter in bipolar DC microgrid are studied in detail. According to the characteristics of bi-directional energy flow, it is divided into three-level Boost converter and three-level Buck converter. The three-level Boost converter in wind power unit is studied, and the state space mathematical model of the converter is established. Second, the relationship between the operation state and the input and output of the converter is analyzed. Second, the three-level Boost converter in the wind power unit is studied. The control strategy of wind power unit based on three-level Boost converter is studied emphatically. The model of each part of wind power unit is established, and the operating characteristics of wind turbine unit under different wind speed are analyzed. The maximum power point tracking control (MPPT) in the region of constant wind power utilization coefficient and constant speed in high wind speed region are proposed. Constant power control strategy. According to the output characteristics of three-level Boost converter. The midpoint potential balance control is designed to ensure the voltage balance of split capacitor. Finally, the effectiveness of wind power unit strategy is verified by Matlab/Simulink simulation. Stable operation in the wind speed zone. The smooth switching between regions is realized and the utilization efficiency of wind energy is improved. Third. The control strategy of energy storage unit based on three-level bi-directional DC-DC converter is studied, and the working principle and equivalent circuit model of supercapacitor are analyzed. According to the voltage fluctuation range of DC bus, the operation of supercapacitor is divided into three stages: no action, droop control, constant current charge and discharge. A control strategy of charging and discharging mode separation is proposed. Finally, the rationality of the control strategy of energy storage unit is verified by Matlab/Simulink simulation. The control strategy is in charge mode or discharge mode. It only takes two switches to switch on. The complexity of the control is reduced. In 4th, the operation control strategy of wind storage bipolar DC microgrid bus is proposed, and the structure of wind storage bipolar DC microgrid and the power balance relationship are analyzed. According to the different states of microgrid, the bus voltage is divided into four operation areas. The wind power characteristic control of wind power unit and the power limit control based on droop characteristic are carried out. The charge / discharge separation control of the energy storage unit and the load reduction control of the load unit realize the stable operation of each state and the smooth switching of each interval. 5th, the wind power unit is built. The performance of the control strategy under different bus voltages and switching between different states is verified by experiments on supercapacitor energy storage device and bipolar DC microgrid with DC load. The busbar voltage division operation control strategy can adjust the bus voltage and balance the system power, thus ensuring the stable operation of the wind storage bipolar DC microgrid.
【學位授予單位】：太原理工大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TM46;TM727

【參考文獻】

相關期刊論文 前10條

1 王毅;于明;李永剛;;基于模型預測控制方法的風電直流微網(wǎng)集散控制[J];電工技術學報;2016年21期

2 劉振亞;;全球能源互聯(lián)網(wǎng)跨國跨洲互聯(lián)研究及展望[J];中國電機工程學報;2016年19期

3 汪飛;雷志方;徐新蔚;;面向直流微電網(wǎng)的電壓平衡器拓撲結構研究[J];中國電機工程學報;2016年06期

4 朱曉榮;蔡杰;王毅;馮亞東;胡仙來;;風儲直流微網(wǎng)虛擬慣性控制技術[J];中國電機工程學報;2016年01期

5 曾鳴;楊雍琦;劉敦楠;曾博;歐陽邵杰;林海英;韓旭;;能源互聯(lián)網(wǎng)“源 網(wǎng) 荷 儲”協(xié)調優(yōu)化運營模式及關鍵技術[J];電網(wǎng)技術;2016年01期

6 李霞林;郭力;王成山;李運帷;;直流微電網(wǎng)關鍵技術研究綜述[J];中國電機工程學報;2016年01期

7 別朝紅;林雁翎;張建華;;微網(wǎng)技術及其標準體系的研究[J];高電壓技術;2015年10期

8 李軍徽;穆鋼;崔新振;葛延峰;高鳳杰;金鵬;;雙鋰電池 電容器混合儲能系統(tǒng)控制策略設計[J];高電壓技術;2015年10期

9 胡長斌;王鑫;羅珊娜;李正熙;楊旭;孫力;;微電網(wǎng)多微源能量優(yōu)化協(xié)調控制[J];中國電機工程學報;2015年S1期

10 熊雄;葉林;楊仁剛;;電力需求側規(guī)模儲能容量優(yōu)化和經(jīng)濟性分析[J];電力系統(tǒng)自動化;2015年17期

相關碩士學位論文 前8條

1 趙耀民;雙層母線直流微電網(wǎng)協(xié)調控制策略研究[D];太原理工大學;2016年

2 田龍剛;光儲交直流混合微電網(wǎng)拓撲分析與控制策略研究[D];合肥工業(yè)大學;2016年

3 張偉偉;交直流混合微網(wǎng)三電平變換器控制研究[D];北京交通大學;2015年

4 竺健;光伏—燃料電池—蓄電池微電網(wǎng)系統(tǒng)研究[D];杭州電子科技大學;2015年

5 布赫;基于復合儲能的永磁直驅風力發(fā)電系統(tǒng)并網(wǎng)控制研究[D];內蒙古工業(yè)大學;2014年

6 趙超群;永磁直驅風力發(fā)電機組三電平變流器技術研究[D];沈陽工業(yè)大學;2013年

7 施婕;分布式電源入網(wǎng)機制及微電網(wǎng)的穩(wěn)定性研究[D];上海交通大學;2010年

8 張義;直驅式永磁同步風力發(fā)電系統(tǒng)的控制研究[D];天津大學;2007年

，

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