本文關(guān)鍵詞：運(yùn)用于三相電壓源型逆變器的諧波電壓電流控制策略研究　出處：《浙江大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 微電網(wǎng) 三相逆變器 下垂控制 諧波控制 諧振控制 RT-LAB

【摘要】：以分布式電源為發(fā)電單元的微電網(wǎng)的研究已然成為新能源研究的熱點(diǎn)之一。歐美、日本等發(fā)達(dá)國家和地區(qū)都已經(jīng)建成了微電網(wǎng)的示范性工程。微電網(wǎng)分為直流微電網(wǎng)、交流微電網(wǎng)和混合微電網(wǎng),本文提到的微電網(wǎng)指的是交流微電網(wǎng)。為了實(shí)現(xiàn)并網(wǎng)模式和孤網(wǎng)模式下穩(wěn)定高效地運(yùn)行,微電網(wǎng)中的逆變器的控制顯得尤為重要,將接口變流器等效為帶有內(nèi)阻抗電壓源的下垂控制方法是兼顧多模式微網(wǎng)運(yùn)行的常見控制策略。 并網(wǎng)模式中,微電網(wǎng)通過靜態(tài)開關(guān)與大電網(wǎng)并聯(lián)運(yùn)行。此時(shí)微電網(wǎng)輸出電壓有大電網(wǎng)的支撐不會(huì)出現(xiàn)明顯的不平衡或畸變,但負(fù)載電流可能存在較大諧波,其中以5次和7次諧波所占的比例較大。將畸變電流中的5次和7次諧波電流控制在合理的范圍內(nèi)能降低電流畸變程度,顯著改善供電環(huán)境。論文以5次和7次諧波電流作為控制對象,在諧波旋轉(zhuǎn)坐標(biāo)系下實(shí)現(xiàn)對于諧波電流量的幅值和相位控制,并且將其嵌入到傳統(tǒng)的下垂控制中的控制策略,使并網(wǎng)逆變器不僅能通過下垂控制進(jìn)行功率控制,還能精確輸出諧波電流。這種控制方式將基波控制與諧波控制融合,使逆變器在進(jìn)行功率控制的同時(shí)具備吸收或發(fā)出諧波電流的能力,可使逆變器兼具功率輸出和有源電力濾波器的功能。 孤網(wǎng)模式中,論文首先分析了諧波電壓產(chǎn)生的原因是逆變器的諧波阻抗較大。其中電壓不平衡主要由dq坐標(biāo)系下的2次諧波引起,而電壓畸變主要由dq坐標(biāo)系下的6次諧波和12次諧波引起。然后分析了各次諧波電壓與各次諧波電流相互作用后在功率上的反應(yīng),得出它們與功率間的關(guān)系。隨后在假定輸出電壓平衡且無畸變的情況下,著重說明了諧波電流與諧波功率間的關(guān)系。H-G控制方式正是利用這一關(guān)系,讓輸出電壓通過電導(dǎo)反饋至電流參考,從而減小諧波電壓。另外,諧振控制可以改變諧振點(diǎn)附近的頻率響應(yīng),將其與H-G控制方式融合得到多諧振的H-G控制方式。這種改進(jìn)控制方式可以減小特定諧波頻率處的逆變器阻抗,從而減小逆變器在該頻率點(diǎn)處的諧波電壓輸出。較之H-G控制方式更有針對性,該控制方式針對不同頻率的諧波,按照其比重不同采用不同的電導(dǎo)值進(jìn)行精確控制。因此,即使逆變器在帶有不平衡負(fù)載或非線性負(fù)載時(shí),仍可以保證輸出電壓的低不平衡度和低畸變率。 論文以上述理論為基礎(chǔ)進(jìn)行了仿真和實(shí)驗(yàn)驗(yàn)證,很好地說明了理論分析的準(zhǔn)確性。本文的實(shí)驗(yàn)均是以基于RT-LAB的三相電壓型逆變器為實(shí)驗(yàn)平臺(tái)。
[Abstract]:The research of microgrid with distributed generation unit has become one of the hotspots of new energy research. Japan and other developed countries and regions have built a demonstration project of microgrid, which is divided into DC microgrid, AC microgrid and hybrid microgrid. In this paper, the micro-grid refers to AC microgrid. In order to realize stable and efficient operation in grid-connected mode and isolated mode, the control of inverter in micro-grid is particularly important. It is a common control strategy that the interface converter is equivalent to a droop control method with an internal impedance voltage source. In the grid-connected mode, the micro-grid runs in parallel with the large grid through static switches. At this time, the output voltage of the micro-grid will not appear obvious imbalance or distortion, but the load current may have larger harmonics. The fifth and seventh harmonics account for a large proportion of the distortion current, and the fifth and seventh harmonic currents can reduce the current distortion within a reasonable range. The fifth and seventh harmonic currents are taken as the control objects, and the amplitude and phase of harmonic current are controlled in the harmonic rotation coordinate system. And it is embedded in the traditional droop control strategy, so that the grid-connected inverter can not only control power through droop control. This control method combines the fundamental control with harmonic control, which enables the inverter to absorb or emit harmonic current at the same time of power control. The inverter has the functions of both power output and active power filter. In the isolated grid mode, the paper first analyzes the reason of the harmonic voltage generation is the high harmonic impedance of the inverter, in which the voltage imbalance is mainly caused by the second harmonic in the dq coordinate system. The voltage distortion is mainly caused by the sixth harmonic and the 12th harmonic in the dq coordinate system. Then, the response of the harmonic voltage to the harmonic current is analyzed. Then the relationship between harmonic current and harmonic power is explained under the assumption that the output voltage is balanced and there is no distortion. H-G control mode makes use of this relationship. The output voltage is fed back to the current reference through the conductance to reduce the harmonic voltage. In addition, the resonance control can change the frequency response near the resonance point. A multi-resonant H-G control mode is obtained by merging it with H-G control mode, which can reduce the inverter impedance at a specific harmonic frequency. Therefore, the harmonic voltage output of inverter at this frequency point is reduced. Compared with H-G control mode, the control mode is more targeted to different frequency harmonics. According to the specific gravity of the inverter, different conductance values are used for accurate control. Therefore, even if the inverter has unbalanced or nonlinear load, it can still guarantee the low unbalance and low distortion rate of the output voltage. The accuracy of the theoretical analysis is well illustrated by the simulation and experimental verification based on the above theory. All the experiments in this paper are based on the three-phase voltage source inverter based on RT-LAB.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TM464

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 羅安;吳傳平;彭雙劍;;諧波治理技術(shù)現(xiàn)狀及其發(fā)展[J];大功率變流技術(shù);2011年06期

2 樂健;姜齊榮;韓英鐸;;三相四線并聯(lián)APF的電流滯環(huán)控制策略分析[J];電力系統(tǒng)自動(dòng)化;2006年17期

3 范小波;張代潤;孫茜;鄭照紅;李萍;;三相三線有源電力濾波器滯環(huán)電流控制策略[J];電力系統(tǒng)自動(dòng)化;2007年18期

4 魯宗相;王彩霞;閔勇;周雙喜;呂金祥;王云波;;微電網(wǎng)研究綜述[J];電力系統(tǒng)自動(dòng)化;2007年19期

5 梁有偉,胡志堅(jiān),陳允平;分布式發(fā)電及其在電力系統(tǒng)中的應(yīng)用研究綜述[J];電網(wǎng)技術(shù);2003年12期

6 劉楊華;吳政球;涂有慶;黃慶云;羅華偉;;分布式發(fā)電及其并網(wǎng)技術(shù)綜述[J];電網(wǎng)技術(shù);2008年15期

7 鄭漳華;艾芊;;微電網(wǎng)的研究現(xiàn)狀及在我國的應(yīng)用前景[J];電網(wǎng)技術(shù);2008年16期

8 陳國柱;王智強(qiáng);謝川;賀超;李玉玲;;高補(bǔ)償精度并聯(lián)型有源電力濾波器的控制策略[J];高電壓技術(shù);2010年08期

9 唐欣;滕本科;涂春鳴;;并聯(lián)型有源電力濾波器的無功功率選擇性補(bǔ)償方法[J];高電壓技術(shù);2012年06期

10 樓書氫;李青鋒;許化強(qiáng);劉魯?shù)?;國外微電網(wǎng)的研究概況及其在我國的應(yīng)用前景[J];華中電力;2009年03期

，

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