本文選題：微電網(wǎng) + 下垂控制��； 參考：《西南交通大學》2017年碩士論文

【摘要】：為了解決日益嚴峻的能源問題,分布式發(fā)電(Distributed Generation,DG)得到迅速的發(fā)展和廣泛的應用。但DG大量接入電網(wǎng)會對電網(wǎng)產(chǎn)生不利的影響,微電網(wǎng)技術(shù)可以有效解決DG的接入和控制。與傳統(tǒng)電網(wǎng)不同,微電網(wǎng)有兩種運行模式,不僅可以運行于并網(wǎng)模式,與大電網(wǎng)相互配合為負載供電,也可以運行于孤島模式,單獨為負載供電。孤島運行的微電網(wǎng),失去了大電網(wǎng)對其電壓和頻率的支撐,當DG的線路阻抗不相等或DG有本地負荷時,微電網(wǎng)中存在較大的環(huán)流,影響微電網(wǎng)的穩(wěn)定運行。本文主要研究孤島運行模式下,低壓微電網(wǎng)的環(huán)流控制策略,主要進行了如下的工作:首先,簡要介紹了微電網(wǎng)中不同類型的DG常用的控制方法,在此基礎上對微電網(wǎng)的運行控制策略進行了分析,以采用下垂控制的微電網(wǎng)為研究對象,分析了微電網(wǎng)中環(huán)流產(chǎn)生的原因,并推導了線路阻抗與微電網(wǎng)環(huán)流大小的關(guān)系。通過仿真證明,當DG的線路阻抗不相等或DG有本地負荷時,傳統(tǒng)的下垂控制和基于虛擬阻抗的下垂控制對微電網(wǎng)環(huán)流的控制效果都不理想。其次,在對微電網(wǎng)環(huán)流進行分析的基礎上,提出了一種基于自適應虛擬阻抗的控制策略來抑制微電網(wǎng)中的環(huán)流,介紹了控制策略的原理和控制流程。該控制策略利用DG輸出無功功率的差值對虛擬阻抗進行調(diào)整,設計了3種算法來控制虛擬阻抗,使虛擬阻抗能夠跟隨線路阻抗的差值,實現(xiàn)DG輸出無功功率按容量分配,從而抑制微電網(wǎng)中的環(huán)流。對虛擬阻抗上的電壓降落進行了分析,指出當虛擬阻抗的取值過大時,DG輸出端電壓存在嚴重跌落,設計了一種簡單的電壓補償方法,補償虛擬阻抗上的電壓降落。最后,在MATLAB軟件中,建立微電網(wǎng)的仿真模型,對本文提出的環(huán)流控制策略和電壓補償方法進行仿真。通過仿真結(jié)果,驗證了本文提出的控制策略能夠有效抑制微電網(wǎng)中的環(huán)流,即使在虛擬阻抗調(diào)整過程中出現(xiàn)通信故障,環(huán)流控制性能也比基于虛擬阻抗的下垂控制策略更好。當微電網(wǎng)采用本文提出的控制策略時,電壓補償方法可以在不影響無功功率分配的基礎上補償虛擬阻抗上的電壓降落。
[Abstract]:In order to solve the increasingly serious energy problem, distributed Generation (DG) has been rapidly developed and widely used. However, a large number of DG access to the grid will have a negative impact on the grid, micro-grid technology can effectively solve the DG access and control. Different from the traditional power grid, there are two operation modes of microgrid, not only in grid-connected mode, but also in isolated island mode. When the line impedance of DG is not equal or the DG has local load, there is a large circulation in the microgrid, which affects the stable operation of the microgrid. In this paper, the circulation control strategy of low-voltage microgrid in isolated island mode is studied. The main work is as follows: firstly, the common control methods of different types of DG in microgrid are introduced briefly. On this basis, the operation control strategy of microgrid is analyzed. Taking microgrid with droop control as research object, the causes of circulation in microgrid are analyzed, and the relationship between line impedance and circulation size of microgrid is deduced. It is proved by simulation that when the line impedance of DG is not equal or DG has local load, the traditional droop control and the droop control based on virtual impedance are not ideal for microgrid circulation control. Secondly, based on the analysis of microgrid circulation, a control strategy based on adaptive virtual impedance is proposed to suppress the circulation in microgrid. The principle and control flow of the control strategy are introduced. The control strategy adjusts the virtual impedance by using the difference of DG output reactive power, designs three algorithms to control the virtual impedance, enables the virtual impedance to follow the line impedance difference, and realizes the DG output reactive power distribution according to the capacity. Thus the circulation in the microgrid is restrained. The voltage drop on the virtual impedance is analyzed, and it is pointed out that when the value of the virtual impedance is too large, there is a serious drop in the output voltage of DG. A simple voltage compensation method is designed to compensate the voltage drop on the virtual impedance. Finally, in MATLAB software, the simulation model of microgrid is established, and the circulation control strategy and voltage compensation method proposed in this paper are simulated. The simulation results show that the proposed control strategy can effectively suppress the circulation in the microgrid. Even if there is a communication fault in the process of virtual impedance adjustment, the performance of the loop control is better than that of the droop control strategy based on virtual impedance. When the control strategy proposed in this paper is adopted, the voltage compensation method can compensate the voltage drop on the virtual impedance without affecting the reactive power distribution.
【學位授予單位】：西南交通大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TM727

【參考文獻】

相關(guān)期刊論文 前10條

1 張丹;王杰;;國內(nèi)微電網(wǎng)項目建設及發(fā)展趨勢研究[J];電網(wǎng)技術(shù);2016年02期

2 紀禮君;曹煒;黃立勤;杜公言;;考慮電壓降落的虛擬阻抗在下垂控制中的應用[J];上海電力學院學報;2015年06期

3 閆俊麗;彭春華;陳臣;;基于動態(tài)虛擬阻抗的低壓微電網(wǎng)下垂控制策略[J];電力系統(tǒng)保護與控制;2015年21期

4 高超;楊其國;李永星;;微電網(wǎng)關(guān)鍵控制技術(shù)綜述[J];自動化技術(shù)與應用;2015年03期

5 王成山;周越;;微電網(wǎng)示范工程綜述[J];供用電;2015年01期

6 蘇小玲;韓民曉;孫海;;基于自適應全局滑�？刂频奈㈦娋W(wǎng)穩(wěn)定控制策略[J];中國電機工程學報;2014年31期

7 趙敏;;基于可再生能源接入海島直流微電網(wǎng)的探討[J];電力系統(tǒng)及其自動化學報;2014年07期

8 馬添翼;金新民;;基于自適應負序電流虛擬阻抗的微電網(wǎng)不平衡控制策略[J];電力系統(tǒng)自動化;2014年12期

9 張平;石健將;李榮貴;龍江濤;何湘寧;;低壓微網(wǎng)逆變器的“虛擬負阻抗”控制策略[J];中國電機工程學報;2014年12期

10 楊新法;蘇劍;呂志鵬;劉海濤;李蕊;;微電網(wǎng)技術(shù)綜述[J];中國電機工程學報;2014年01期

，

本文編號：1799650