【摘要】：多電平變換器以其電能質(zhì)量高、效率高、功率大等特點(diǎn)被廣泛應(yīng)用在高壓大功率領(lǐng)域,但隨著該領(lǐng)域?qū)ψ儞Q器的性能和功能需求的不斷增加,傳統(tǒng)的結(jié)構(gòu)的變換器越來越顯現(xiàn)出其不足,比如所需功率器件較多、結(jié)構(gòu)較為復(fù)雜、功能性不足等問題。混合逆變器能夠采用更少的功率器件實(shí)現(xiàn)較多的輸出電平,從而可以簡(jiǎn)化變流器結(jié)構(gòu),降低成本,減小體積。混合逆變器主要是指由不同電壓等級(jí)、不同結(jié)構(gòu)的功率單元或不同功率等級(jí)的開關(guān)器件組合成的電力電子變換器,這種組合可以使混合逆變器繼承原始功率單元的某種特性,從而達(dá)到改善其工作特性的目的。本文以兩種混合逆變器為研究對(duì)象,對(duì)其各自的工作特性與控制方法做了研究,一種是混合級(jí)聯(lián)7電平逆變器和另一種是混合級(jí)聯(lián)多電平靜止同步補(bǔ)償器。混合級(jí)聯(lián)7電平逆變器使用較少的開關(guān)器件實(shí)現(xiàn)了較高的電能質(zhì)量,但是混合調(diào)制法會(huì)使其低壓?jiǎn)卧绷鱾?cè)發(fā)生電流倒灌問題,不利于其實(shí)用化。混合頻率載波調(diào)制法可以解決電流倒灌問題,但是其高壓?jiǎn)卧\(yùn)行頻率過低,對(duì)其電能質(zhì)量有很大影響,因此提出了改進(jìn)混合頻率載波調(diào)制法。改進(jìn)后的方法利用單極倍頻調(diào)制使高壓?jiǎn)卧陂_關(guān)頻率不變的情況下等效載波頻率加倍,即提高了輸出電能質(zhì)量,又保留了混合頻率載波調(diào)制法可消除功率環(huán)流的優(yōu)點(diǎn)。對(duì)裝置的多重化整流電路進(jìn)行了研究,并證明了其不存在功率環(huán)流。最后,在MATLAB/Simulink下進(jìn)行了仿真,驗(yàn)證了所提出的方法�；旌霞�(jí)聯(lián)多電平靜止同步補(bǔ)償器(HCMC-STATCOM)結(jié)合了三相橋逆變器結(jié)構(gòu)簡(jiǎn)單與級(jí)聯(lián)H橋逆變器輸出電能質(zhì)量好的優(yōu)點(diǎn)。由于三相橋單元存在公共直流側(cè),其可進(jìn)行相間能量交換,因此具有一定的不平衡電流補(bǔ)償能力。對(duì)HCMC-STATCOM的補(bǔ)償原理進(jìn)行了研究,首先推導(dǎo)了HCMC-STATCOM整形電路直流側(cè)平衡所需的零序電壓,然后求出了HCMC-STATCOM可補(bǔ)償電流的不平衡度范圍。與相同輸出電壓水平的鏈?zhǔn)叫切蜸TATCOM相比,HCMC-STATCOM的補(bǔ)償范圍更廣。研究了HCMC-STATCOM的控制系統(tǒng),通過正、負(fù)序分開解耦的方法完成了對(duì)補(bǔ)償電流的控制,并且給出了其三相橋單元與整形電路的直流側(cè)平衡控制策略。最后,對(duì)HCMC-STATCOM在MATLAB/Simulink仿真平臺(tái)下搭建了模型,仿真結(jié)果與理論分析基本一致。
[Abstract]:Multilevel converters are widely used in high-voltage and high-power fields because of their high power quality, high efficiency and high power. However, with the increasing demand for the performance and function of the converters in this field, Traditional converters have more and more disadvantages, such as more power devices needed, more complex structure, insufficient function and so on. The hybrid inverter can use fewer power devices to achieve more output levels, which can simplify the converter structure, reduce cost and reduce the volume. Hybrid inverters mainly refer to power electronic converters composed of different power units with different voltage levels, different structures or switching devices of different power levels. This combination can enable the hybrid inverter to inherit some characteristics of the original power unit. In order to achieve the purpose of improving its working characteristics. In this paper, two hybrid inverters are studied, and their respective working characteristics and control methods are studied. One is a hybrid cascaded 7-level inverter and the other is a hybrid cascade multilevel static synchronous compensator. The hybrid cascaded 7-level inverter uses fewer switching devices to achieve high power quality, but the hybrid modulation method will cause the DC side of the low voltage cell to produce current backflow problem, which is not conducive to its practicality. The hybrid frequency carrier modulation method can solve the problem of current backflow, but its high voltage unit has low operating frequency, which has great influence on its power quality. Therefore, an improved hybrid frequency carrier modulation method is proposed. The improved method uses unipolar frequency doubling modulation to double the equivalent carrier frequency of the high voltage unit under the condition of constant switching frequency, which not only improves the output power quality, but also retains the advantage that the hybrid frequency carrier modulation method can eliminate the power circulation. The multiplex rectifier circuit of the device is studied, and it is proved that there is no power circulation. Finally, simulation is carried out in MATLAB / Simulink to verify the proposed method. Hybrid cascaded multilevel static synchronous compensator (HCMC-STATCOM) combines the advantages of simple structure of three-phase bridge inverter and good output power quality of cascaded H-bridge inverter. Because of the common DC side of the three-phase bridge element, it can exchange energy between phases, so it has a certain compensation ability of unbalanced current. The compensation principle of HCMC-STATCOM is studied. The zero-sequence voltage required for DC side balance of HCMC-STATCOM shaping circuit is derived, and the unbalance range of compensating current of HCMC-STATCOM is obtained. The compensation range of HCMC-STATCOM is wider than that of chain star Statcom with the same output voltage level. The control system of HCMC-STATCOM is studied. The compensation current is controlled by decoupling the positive and negative sequence, and the balance control strategy of the three-phase bridge unit and the shaping circuit is given. Finally, the model of HCMC-STATCOM based on MATLAB / Simulink simulation platform is built, and the simulation results are in good agreement with the theoretical analysis.
【學(xué)位授予單位】：蘭州交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TM464

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 徐瑩;趙鵬豪;趙成勇;許建中;江偉;別曉玉;;橋臂交替導(dǎo)通換流器的模塊最優(yōu)冗余配置方法[J];電力系統(tǒng)自動(dòng)化;2017年02期

2 鄭劍飛;應(yīng)建平;胡志明;;基于混合拓?fù)涞闹袎红o止無功發(fā)生器的研究[J];電器與能效管理技術(shù);2016年20期

3 湯廣福;龐輝;賀之淵;;先進(jìn)交直流輸電技術(shù)在中國(guó)的發(fā)展與應(yīng)用[J];中國(guó)電機(jī)工程學(xué)報(bào);2016年07期

4 李宋;葉滿園;;混合級(jí)聯(lián)多電平逆變器混合頻率載波調(diào)制技術(shù)[J];高電壓技術(shù);2015年07期

5 季振東;孫毅超;李東野;趙劍鋒;黃允凱;;星形和三角形連接的鏈?zhǔn)紿橋STATCOM不平衡補(bǔ)償分析[J];高電壓技術(shù);2015年07期

6 杜翼;江道灼;林志勇;尹瑞;王玉芬;梁一橋;;混合級(jí)聯(lián)多電平換流器型靜止同步補(bǔ)償器的優(yōu)化設(shè)計(jì)[J];電力系統(tǒng)自動(dòng)化;2015年06期

7 張國(guó)榮;沈奇;;單相有源電力濾波器直流側(cè)電容與電壓波動(dòng)關(guān)系分析及設(shè)計(jì)[J];電力系統(tǒng)自動(dòng)化;2015年04期

8 金淵;梁暉;陳彪;;七電平混合級(jí)聯(lián)型光伏并網(wǎng)逆變器研究[J];電工技術(shù)學(xué)報(bào);2015年04期

9 耿俊利;梁暉;金淵;;基于SVPWM調(diào)制的混合級(jí)聯(lián)七電平逆變器優(yōu)化控制策略[J];電網(wǎng)技術(shù);2015年02期

10 邱長(zhǎng)青;黃聲華;;抑制直流母線電壓波動(dòng)的四象限級(jí)聯(lián)型變頻器前饋控制策略[J];電網(wǎng)技術(shù);2015年01期

相關(guān)博士學(xué)位論文 前2條

1 張?jiān)?非對(duì)稱混合多電平逆變器調(diào)制策略及功率均衡控制研究[D];哈爾濱工業(yè)大學(xué);2010年

2 孫醒濤;混合不對(duì)稱多電平逆變器拓?fù)浼翱刂撇呗缘难芯縖D];哈爾濱工業(yè)大學(xué);2009年

相關(guān)碩士學(xué)位論文 前6條

1 宋振浩;混合級(jí)聯(lián)H橋型STATCOM調(diào)制策略研究[D];中國(guó)礦業(yè)大學(xué);2016年

2 陳偉;三角形鏈?zhǔn)届o止同步補(bǔ)償器補(bǔ)償不平衡負(fù)載能力分析及控制[D];重慶大學(xué);2015年

3 閻宏;功率單元級(jí)聯(lián)型SVG控制策略的研究[D];蘭州交通大學(xué);2014年

4 林志勇;基于混合級(jí)聯(lián)多電平換流器的STATCOM研究[D];浙江大學(xué);2014年

5 張艷芳;用于不平衡負(fù)載補(bǔ)償?shù)腄-STATCOM控制方法的研究[D];西安理工大學(xué);2009年

6 黃慶利;一種新型混合級(jí)聯(lián)逆變器的研究[D];中南大學(xué);2008年

，

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