發(fā)布時(shí)間：2018-04-02 09:39

  本文選題：孤島電網(wǎng)　切入點(diǎn)：頻率穩(wěn)定　出處：《沈陽(yáng)工業(yè)大學(xué)》2017年碩士論文

【摘要】：微電網(wǎng)是一種將分布式電源、負(fù)荷、儲(chǔ)能裝置、變流器以及監(jiān)控保護(hù)裝置有機(jī)整合在一起的小型發(fā)配電系統(tǒng)。微電網(wǎng)解決了分散式并網(wǎng)難的問(wèn)題,提升了風(fēng)電的利用率。隨著風(fēng)電滲透率的增加,微網(wǎng)頻率波動(dòng)進(jìn)一步加劇,孤網(wǎng)模式下頻率波動(dòng)尤為嚴(yán)重。本文針對(duì)孤網(wǎng)中負(fù)荷增加與風(fēng)速波動(dòng)引起頻率跌落及小幅度振蕩問(wèn)題展開(kāi)研究,通過(guò)改進(jìn)變流器的控制策略解決孤島電網(wǎng)低頻震蕩問(wèn)題。首先,建立永磁發(fā)電機(jī)和變流器的數(shù)學(xué)模型,分析永磁風(fēng)電機(jī)組有功功率控制特點(diǎn),采用矢量控制策略實(shí)現(xiàn)風(fēng)電機(jī)組有功、無(wú)功解耦控制,為后續(xù)研究提供理論基礎(chǔ)。其次,分析孤網(wǎng)功率平衡特性,針對(duì)孤網(wǎng)中轉(zhuǎn)動(dòng)慣量控制策略出現(xiàn)頻率二次跌落問(wèn)題提出降載荷控制策略。在低風(fēng)速區(qū),風(fēng)電機(jī)組追蹤次優(yōu)功率曲線超速減載運(yùn)行,保留有功備用余量為風(fēng)電機(jī)組參與孤島電網(wǎng)調(diào)頻做準(zhǔn)備。在高風(fēng)速區(qū),協(xié)調(diào)變槳距角控制策略與降載荷控制策略,在確保風(fēng)電機(jī)組穩(wěn)定運(yùn)行的前提下,保留充足的有功功率備用余量支撐孤島電網(wǎng)頻率的穩(wěn)定性。所提降載荷控制策略,在高、低風(fēng)速區(qū)均解決頻率二次跌落問(wèn)題。再次,針對(duì)單一降載荷控制策略不能有效解決低頻震蕩問(wèn)題,本文提出協(xié)調(diào)機(jī)側(cè)分段減載與網(wǎng)側(cè)模糊下垂的聯(lián)合控制策略。分段減載控制策略在分析不同降載荷系數(shù)功頻特性的基礎(chǔ),對(duì)全風(fēng)速范圍進(jìn)行劃分,在不同風(fēng)速區(qū)間確定合適的降載系數(shù),解決單一降載荷控制策略下有功功率備用余量不足的問(wèn)題,增強(qiáng)風(fēng)電機(jī)組對(duì)孤島電網(wǎng)頻率穩(wěn)定性的支撐作用。網(wǎng)側(cè)模糊下垂控制策略,通過(guò)設(shè)計(jì)模糊控制器和模糊規(guī)則,建立了孤島電網(wǎng)頻率偏差、頻率變化率與風(fēng)電機(jī)組補(bǔ)償功率間的聯(lián)系,優(yōu)化了變流器的輸入輸出功率,有效抑制孤網(wǎng)頻率驟降,解決低頻震蕩問(wèn)題。最后,在Matlab/Simulink仿真環(huán)境中,搭建不同控制策略下風(fēng)電機(jī)組參與孤島電網(wǎng)調(diào)頻時(shí)的仿真模型,進(jìn)行仿真驗(yàn)證。結(jié)果表明聯(lián)合控制策略下,永磁風(fēng)電機(jī)組的運(yùn)行狀態(tài)最穩(wěn)定,孤島電網(wǎng)頻率波動(dòng)最小。在仿真的基礎(chǔ)上,通過(guò)實(shí)驗(yàn)進(jìn)一步驗(yàn)證聯(lián)合控制策略可行性和有效性。
[Abstract]:Microgrid is a small power generation and distribution system that integrates distributed power sources, loads, energy storage devices, converters, and monitoring and protection devices.Microgrid solves the difficult problem of decentralized grid connection and improves the utilization rate of wind power.With the increase of wind power permeability, the frequency fluctuation of microgrid is further aggravated, especially in the isolated grid mode.In this paper, the problem of frequency drop and small amplitude oscillation caused by load increase and wind speed fluctuation in isolated network is studied, and the problem of low frequency oscillation in isolated island power network is solved by improving the control strategy of converter.Firstly, the mathematical model of permanent magnet generator and converter is established, and the characteristics of active power control of permanent magnet wind turbine are analyzed. The vector control strategy is used to realize the decoupling control of active power and reactive power of wind turbine, which provides a theoretical basis for further research.Secondly, the power balance characteristics of the isolated network are analyzed, and a load reduction control strategy is proposed for the frequency secondary drop of the moment of inertia control strategy in the isolated network.In the low wind speed area, wind turbines track the sub-optimal power curve to overspeed and reduce the load, and reserve the active power reserve for the wind turbine to participate in the frequency modulation of the isolated island power network.In the high wind speed region, the variable pitch angle control strategy and the load reduction control strategy are coordinated. Under the premise of ensuring the stable operation of the wind turbine, sufficient active power reserve is reserved to support the stability of the isolated island power network frequency.The proposed load control strategy solves the problem of frequency secondary drop in high and low wind speed regions.Thirdly, since a single load reduction control strategy can not effectively solve the problem of low frequency oscillation, this paper proposes a joint control strategy of coordinating segment load reduction on the side of the machine and fuzzy droop on the grid side.The piecewise load reduction control strategy is based on analyzing the power and frequency characteristics of different load reduction coefficients, dividing the whole wind speed range, and determining the appropriate load reduction coefficients in different wind speed ranges.To solve the problem of insufficient spare allowance of active power under a single load reduction control strategy, and to enhance the support function of wind turbine to the frequency stability of isolated island power network.By designing fuzzy controller and fuzzy rules, the relationship among frequency deviation, frequency change rate and compensation power of wind turbine is established, and the input and output power of converter is optimized.Effectively restrain the frequency drop of the isolated network and solve the problem of low frequency oscillation.Finally, in the Matlab/Simulink simulation environment, the simulation model of wind turbine participating in frequency modulation of isolated island power network is built under different control strategies, and the simulation results are verified.The results show that the operation state of permanent magnet wind turbine is the most stable and the frequency fluctuation of isolated island power network is minimum under the joint control strategy.On the basis of simulation, the feasibility and effectiveness of the joint control strategy are further verified by experiments.
【學(xué)位授予單位】：沈陽(yáng)工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TM712;TM614

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 楊俊友;王海鑫;井艷軍;邢作霞;崔嘉;;并網(wǎng)型風(fēng)電機(jī)組模擬控制策略[J];電機(jī)與控制學(xué)報(bào);2016年03期

2 王海鑫;楊俊友;李欣;邢作霞;崔嘉;李連富;王宇帆;李春來(lái);;電網(wǎng)故障下直驅(qū)永磁風(fēng)力發(fā)電機(jī)組機(jī)側(cè)變流器改進(jìn)控制策略[J];可再生能源;2015年11期

3 郭權(quán)利;苑舜;周春陽(yáng);王昊;王雪杰;;基于模糊控制的微網(wǎng)平滑切換控制策略的研究[J];高電壓技術(shù);2015年10期

4 楊俊友;王海鑫;邢作霞;崔嘉;張華友;李美征;黎明;;孤島模式下潮流能發(fā)電系統(tǒng)協(xié)調(diào)控制策略[J];電工技術(shù)學(xué)報(bào);2015年14期

5 侍喬明;王剛;馬偉明;付立軍;徐力;劉洋;;直驅(qū)永磁風(fēng)電機(jī)組虛擬慣量控制的實(shí)驗(yàn)方法研究[J];中國(guó)電機(jī)工程學(xué)報(bào);2015年08期

6 呂志鵬;盛萬(wàn)興;鐘慶昌;劉海濤;曾正;楊亮;劉嵐;;虛擬同步發(fā)電機(jī)及其在微電網(wǎng)中的應(yīng)用[J];中國(guó)電機(jī)工程學(xué)報(bào);2014年16期

7 姜世公;李琰;王衛(wèi);;一種微網(wǎng)系統(tǒng)孤島運(yùn)行條件下的能量管理策略[J];電工技術(shù)學(xué)報(bào);2014年02期

8 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(guó)電機(jī)工程學(xué)報(bào);2014年01期

9 孫孝峰;王娟;田艷軍;李昕;;基于自調(diào)節(jié)下垂系數(shù)的DG逆變器控制[J];中國(guó)電機(jī)工程學(xué)報(bào);2013年36期

10 徐少華;李建林;;光儲(chǔ)微網(wǎng)系統(tǒng)并網(wǎng)/孤島運(yùn)行控制策略[J];中國(guó)電機(jī)工程學(xué)報(bào);2013年34期

相關(guān)博士學(xué)位論文 前2條

1 張洪陽(yáng);永磁風(fēng)力發(fā)電機(jī)分布式直流并網(wǎng)變流器的研究與實(shí)現(xiàn)[D];沈陽(yáng)工業(yè)大學(xué);2011年

2 李軍軍;并網(wǎng)型風(fēng)力發(fā)電系統(tǒng)的小擾動(dòng)穩(wěn)定性分析研究[D];湖南大學(xué);2011年

相關(guān)碩士學(xué)位論文 前1條

1 焦平洋;雙饋風(fēng)電機(jī)組參與微網(wǎng)調(diào)頻的控制策略研究[D];哈爾濱工業(yè)大學(xué);2015年

，

本文編號(hào)：1699796