本文選題：混合電網(wǎng) + 模塊化多電平變換器��； 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：隨著化石能源的日漸減少以及利用過程中對環(huán)境產(chǎn)生的污染,以可再生能源為基礎(chǔ)的分布式發(fā)電將會是未來發(fā)電領(lǐng)域中的一個重要組成部分�？稍偕茉淳哂虚g歇性和多樣性等特點,如果發(fā)出的電能直接并入交流電網(wǎng)會影響系統(tǒng)的穩(wěn)定運行。采用交直流電網(wǎng)并存的混合電網(wǎng)可以很好的對發(fā)出的電能進行傳輸和利用。而不同類型的電網(wǎng)間需要采用變換器進行連接,模塊化多電平變換器(MMC)由于其自身的優(yōu)點,非常適合于中高壓、大功率情況下混合電網(wǎng)間的能量傳遞。本文以混合電網(wǎng)中的模塊化多電平變換器為研究對象,首先分析其拓撲結(jié)構(gòu),并對環(huán)流成分進行分析。針對環(huán)流諧波抑制問題,本文提出一種基于魯棒H?控制的MMC電流控制,通過使環(huán)流趨于設(shè)定值來控制環(huán)流各分量的大小,從而能夠消除環(huán)流諧波中的主要成分,進而使系統(tǒng)運行更加穩(wěn)定。然后,針對MMC交流側(cè)處于弱電網(wǎng)工況時,電網(wǎng)間能量傳輸不穩(wěn)定進而導(dǎo)致系統(tǒng)運行不穩(wěn)定的問題,提出一種基于虛擬同步發(fā)電機(VSG)控制的MMC能量控制。通過對電力系統(tǒng)中同步發(fā)電機的轉(zhuǎn)速特性和勵磁特性的模擬,設(shè)計功頻控制器和勵磁控制器對交流側(cè)處于弱電網(wǎng)工況的MMC進行控制,使系統(tǒng)在弱電網(wǎng)工況下也能正常運行。接著,針對變換器輸出阻抗對系統(tǒng)運行可能產(chǎn)生的影響,對變換器輸出阻抗的分析,可以預(yù)測系統(tǒng)的穩(wěn)定性。本文提出一種基于變換器輸出阻抗的小信號分析方法,對變換器阻抗、采用鎖相環(huán)和所提虛擬同步發(fā)電機控制時變換器的輸出阻抗進行分析。最后,在MMC實驗樣機平臺上,對所提出的控制策略進行實驗驗證。實驗結(jié)果表明所提控制策略正確、有效。
[Abstract]:As to the environment and the use of fossil energy is reduced in the process of pollution, will be distributed generation based on renewable energy is a future generation in the field of an important part. Renewable energy has the characteristics of intermittent and diversity, if electricity is directly incorporated into will affect the stable operation of the system using the AC network. Hybrid AC / DC power grid power grid coexistence can be very good for transmission and utilization of electricity. Which require the use of converter to connect different types of grid, the modular multilevel converter (MMC) because of its advantages, is very suitable for high voltage transmission, hybrid power grid energy between high power based on the hybrid power grid. The modular multilevel converter as the research object, firstly analyses the topology structure, and the circulation composition analysis. The harmonic suppression in circulation For problems, this paper proposes a robust H? MMC current control control, through the circulation tends to set value to control the circulation of each component size, which can eliminate the main harmonic components in circulation, and make the system more stable. Then, according to the MMC AC side in the weak power grid operation, power grid energy transmission is not stable and lead to system instability problems, put forward a virtual synchronous generator (VSG) based on MMC energy control. Through the simulation speed characteristic and excitation characteristics of synchronous generator in power system, the design of power frequency controller and excitation controller of the AC side in the weak network condition of the MMC control, the the system can run normally in the weak network condition. Then, in view of the influence of converter output impedance of the system may have the operation, analysis of the converter output impedance of the system can be predicted Stability. This paper proposed an analysis method of small signal converter based on output impedance, impedance converter, phase locked loop and the analysis of the output impedance converter virtual synchronous generator control. Finally, the prototype of the MMC platform, in order to verify the validity of the proposed control strategy. The experimental results show that the proposed control strategy is correct and effective.

【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TM46

【參考文獻】

相關(guān)期刊論文 前1條

1 郭威;趙冬梅;呂志鵬;;利用容性輸出阻抗的逆變器解決風(fēng)機的無功補償問題[J];華東電力;2014年02期

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本文編號：1746708