民用非線性負(fù)荷諧波模型及集合效應(yīng)研究
本文選題:電能質(zhì)量 + 非線性負(fù)荷。 參考:《山東大學(xué)》2017年碩士論文
【摘要】:近年來(lái),在節(jié)能發(fā)展主題意識(shí)的驅(qū)動(dòng)下,電力電子技術(shù)發(fā)展地異常迅速。在低壓配電系統(tǒng)中,含電力電子整流環(huán)節(jié)的家用電器類(lèi)諧波源占據(jù)了越來(lái)越大的比重。通常,該類(lèi)諧波源的單臺(tái)功率很小,但是其產(chǎn)生的諧波電流總畸變率都在100%上下,有時(shí)候甚至更嚴(yán)重。因此,該類(lèi)諧波源負(fù)荷的大量使用勢(shì)必會(huì)對(duì)整個(gè)電力系統(tǒng)造成諧波污染。傳統(tǒng)諧波分析方法是把各諧波源看作恒流源,對(duì)諧波源的集合效應(yīng)不給予考慮,這樣往往容易造成對(duì)電網(wǎng)諧波發(fā)射水平的不準(zhǔn)確評(píng)估。本文聚焦民用非線性負(fù)荷的諧波發(fā)射水平研究。一方面,通過(guò)分析典型家用電器的等值電路的運(yùn)行機(jī)理,建立了一種精確的諧波耦合導(dǎo)納矩陣數(shù)學(xué)模型,并提出了一種計(jì)算多諧波源總電流的理論;另一方面,利用建立的精確諧波耦合導(dǎo)納矩陣數(shù)學(xué)模型以及所提出的計(jì)算多諧波源系統(tǒng)總電流的理論,從定量分析的角度對(duì)民用非線性負(fù)荷的諧波集合效應(yīng)進(jìn)行了研究。論文的主要內(nèi)容及突出成果如下:(1)詳細(xì)分析典型家用電器等值電路的運(yùn)行機(jī)理,借助傅里葉變換在頻域中建立了能準(zhǔn)確反映典型家用電器等值電路諧波產(chǎn)生特性的精確諧波耦合導(dǎo)納矩陣數(shù)學(xué)模型。整個(gè)建模過(guò)程中未涉及近似等效問(wèn)題,克服了原模型由于對(duì)等值電路直流側(cè)電壓采取近似處理而導(dǎo)致模型存在不同程度誤差的問(wèn)題。此外,采用高斯-賽德?tīng)柗ê团nD-拉夫遜法配合使用的方法對(duì)等值電路對(duì)應(yīng)的導(dǎo)通角和關(guān)斷角進(jìn)行精確計(jì)算,從而進(jìn)一步提高所建立的諧波耦合導(dǎo)納矩陣數(shù)學(xué)模型的準(zhǔn)確度。模型計(jì)算和時(shí)域仿真的對(duì)比結(jié)果證明了論文所建模型的精確性。(2)提出一種計(jì)算民用多諧波源系統(tǒng)總電流的方法。利用該方法計(jì)算系統(tǒng)總電流的多個(gè)算例的編程計(jì)算結(jié)果和相應(yīng)的時(shí)域仿真結(jié)果的對(duì)比證明了該方法具有較好的適用性。(3)基于所建立的典型家用電器等值電路的精確諧波耦合導(dǎo)納矩陣數(shù)學(xué)模型以及所提出的計(jì)算民用多諧波源系統(tǒng)總電流的理論,從定量分析的角度分別對(duì)民用多諧波源系統(tǒng)的諧波衰減效應(yīng)、分散效應(yīng)以及集合效應(yīng)進(jìn)行了研究。研究結(jié)果表明:系統(tǒng)諧波階數(shù)越高,諧波衰減現(xiàn)象越明顯;負(fù)荷側(cè)并聯(lián)的負(fù)荷數(shù)量越多,系統(tǒng)各次諧波衰減的幅度越大,衰減因子AF可很好地衡量系統(tǒng)的諧波衰減程度;不同類(lèi)型的負(fù)荷集各自對(duì)應(yīng)的分散因子DF可以很好地表征不同類(lèi)型負(fù)荷對(duì)系統(tǒng)總諧波分散效應(yīng)的貢獻(xiàn)程度;集合因子CF可直觀地反映系統(tǒng)的諧波集合現(xiàn)象。(4)分析了線性負(fù)荷對(duì)民用多諧波源系統(tǒng)諧波集合效應(yīng)的影響。研究發(fā)現(xiàn),線性負(fù)荷的加入會(huì)使系統(tǒng)總電流的總諧波畸變率減少,并且阻值小的線性負(fù)荷更利于減少系統(tǒng)總電流的總諧波畸變率。
[Abstract]:In recent years, driven by the theme consciousness of energy conservation development, power electronics technology has developed very rapidly. In the low-voltage distribution system, the harmonic source of household appliances with power electronic rectifier is more and more important. Usually, the power of this kind of harmonic source is very small, but the total distortion rate of harmonic current is about 100%, sometimes even more serious. Therefore, the heavy use of this kind of harmonic source load will inevitably cause harmonic pollution to the whole power system. The traditional harmonic analysis method regards each harmonic source as a constant current source and does not consider the collective effect of the harmonic source, which often results in an inaccurate evaluation of the harmonic emission level of the power network. This paper focuses on the harmonic emission level of civil nonlinear load. On the one hand, by analyzing the operation mechanism of equivalent circuit of typical household appliances, a precise mathematical model of harmonic coupling admittance matrix is established, and a theory of calculating the total current of multiple harmonic sources is put forward. Based on the mathematical model of accurate harmonic coupling admittance matrix and the theory of calculating the total current of multi-harmonic source system, the harmonic set effect of civil nonlinear load is studied from the point of view of quantitative analysis. The main contents and outstanding results are as follows: (1) the operation mechanism of equivalent circuit of typical household appliances is analyzed in detail. By means of Fourier transform, a mathematical model of harmonic coupled admittance matrix is established in the frequency domain, which can accurately reflect the harmonic generation characteristics of typical equivalent circuit of household appliances. The problem of approximate equivalence is not involved in the whole modeling process, which overcomes the problem that the original model has different degree of error due to the approximate treatment of DC side voltage of equivalent circuit. In addition, the Gauss-Seadell method and Newton-Raphson method are used to calculate the conduction angle and turn-off angle of equivalent circuit accurately, so as to further improve the accuracy of the mathematical model of harmonic coupling admittance matrix. The results of model calculation and time domain simulation prove the accuracy of the model. (2) A method to calculate the total current of civil multi-harmonic source system is proposed. The comparison of the results of programming calculation and corresponding time domain simulation of the total current of the system shows that the method has good applicability. (3) based on the established equivalent circuit of typical household appliances, the method is proved to be accurate. The mathematical model of harmonic coupled admittance matrix and the theory proposed to calculate the total current of civil multi-harmonic source system are presented. From the point of view of quantitative analysis, the harmonic attenuation effect, dispersion effect and collective effect of civil multi-harmonic source system are studied respectively. The results show that the higher the harmonic order of the system, the more obvious the harmonic attenuation phenomenon is, and the larger the load number at the load side is, the larger the harmonic attenuation amplitude of the system is. The attenuation factor AF can well measure the harmonic attenuation degree of the system. The dispersion factor DF corresponding to different load sets can well characterize the contribution of different types of load to the total harmonic dispersion effect of the system. The set factor CF can directly reflect the harmonic set phenomenon of the system. (4) the influence of linear load on the harmonic set effect of civil multi-harmonic source system is analyzed. It is found that the total harmonic distortion rate of the total current of the system is reduced with the addition of linear load, and the linear load with small resistance value is more favorable to reduce the total harmonic distortion rate of the total current of the system.
【學(xué)位授予單位】:山東大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2017
【分類(lèi)號(hào)】:TM711
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 孫媛媛;劉福朝;李佳奇;張坤;;三相不控VSC的統(tǒng)一化諧波模型及運(yùn)行狀態(tài)判定[J];中國(guó)電機(jī)工程學(xué)報(bào);2016年13期
2 孫媛媛;李佳奇;尹志明;王廣柱;;含不控整流的交 直 交變換器頻域諧波分析模型[J];中國(guó)電機(jī)工程學(xué)報(bào);2015年21期
3 孫媛媛;王小宇;尹志明;;多諧波源系統(tǒng)的非迭代式諧波潮流分析[J];中國(guó)電機(jī)工程學(xué)報(bào);2012年07期
4 雍靜;陳亮;陳雙燕;;臺(tái)式計(jì)算機(jī)負(fù)荷的頻域諧波模型及衰減特性[J];中國(guó)電機(jī)工程學(xué)報(bào);2010年25期
5 鄭偉杰;孫媛媛;徐文遠(yuǎn);;應(yīng)用非線性元件耦合矩陣模型的諧波潮流算法[J];中國(guó)電機(jī)工程學(xué)報(bào);2008年10期
6 王星華;余欣梅;;諧波潮流建模及求解算法研究綜述[J];電氣應(yīng)用;2008年02期
7 袁旭峰;程時(shí)杰;文勁宇;;基于CSC和VSC的混合多端直流輸電系統(tǒng)及其仿真[J];電力系統(tǒng)自動(dòng)化;2006年20期
8 崔威,李建華,趙娟;供電網(wǎng)絡(luò)諧波潮流計(jì)算[J];電力自動(dòng)化設(shè)備;2003年02期
9 盧恩,張步涵,龔世纓;電力系統(tǒng)諧波潮流的一種解耦算法[J];電網(wǎng)技術(shù);2003年02期
10 趙勇,張濤,李建華,夏道止;一種新的諧波源簡(jiǎn)化模型[J];中國(guó)電機(jī)工程學(xué)報(bào);2002年04期
相關(guān)博士學(xué)位論文 前1條
1 孫媛媛;非線性電力電子裝置的諧波源模型及其在諧波分析中的應(yīng)用[D];山東大學(xué);2009年
相關(guān)碩士學(xué)位論文 前1條
1 陳雙燕;低壓?jiǎn)蜗喾蔷性負(fù)荷諧波特性的實(shí)驗(yàn)研究[D];重慶大學(xué);2010年
,本文編號(hào):2056162
本文鏈接:http://www.sikaile.net/kejilunwen/dianlidianqilunwen/2056162.html