本文選題：微電網(wǎng) + 并聯(lián)逆變器�。� 參考：《燕山大學(xué)》2015年碩士論文

【摘要】：由可再生能源、儲(chǔ)能設(shè)備和電力電子裝置等組成的微電網(wǎng)逐漸成為滿足負(fù)荷增長需求的有效方式。隨著大量分布式發(fā)電單元接入,孤島微電網(wǎng)中存在多逆變器并聯(lián)運(yùn)行狀態(tài),受線路阻抗不匹配以及本地負(fù)載等影響易引起功率分配和環(huán)流問題,影響系統(tǒng)穩(wěn)定運(yùn)行。針對(duì)并聯(lián)系統(tǒng)功率分配和環(huán)流問題,本文考慮線路阻抗和本地負(fù)載影響,辨析系統(tǒng)在功率按容量均分和零環(huán)流運(yùn)行狀態(tài)下的聯(lián)系和區(qū)別,并對(duì)比兩種狀態(tài)下線路損耗�？紤]系統(tǒng)效率,本文提出一種基于平均功率的改進(jìn)下垂控制方案。該方案無需分別考慮線路阻抗和本地負(fù)荷等因素對(duì)功率分配的影響,利用功率差產(chǎn)生的電壓偏移量對(duì)電壓幅值進(jìn)行補(bǔ)償以實(shí)現(xiàn)功率分配,減小環(huán)流,并在相同容量和不同容量并聯(lián)系統(tǒng)中均能達(dá)到較好的負(fù)荷分配。為合理設(shè)計(jì)下垂系數(shù),常忽略電壓電流環(huán)等影響,并通過建立下垂環(huán)節(jié)的小信號(hào)模型分析系統(tǒng)穩(wěn)定性。但孤島系統(tǒng)中各分布式發(fā)電單元之間存在諧波交互作用,為此,本文考慮逆變器電壓電流閉環(huán)作用,通過推導(dǎo)孤島系統(tǒng)中公共耦合點(diǎn)電壓與參考電壓和輸出電流的關(guān)系式,建立多機(jī)下垂系統(tǒng)的等效戴維南模型,利用基于阻抗的Nyquist穩(wěn)定判據(jù)判斷系統(tǒng)穩(wěn)定性。理論分析和仿真結(jié)果證明了線路阻抗和逆變器并聯(lián)數(shù)量對(duì)系統(tǒng)諧波穩(wěn)定性的重要影響。最后,本文基于TMS320F2812的DSP搭建三相逆變器并聯(lián)實(shí)驗(yàn)平臺(tái)進(jìn)行實(shí)驗(yàn)驗(yàn)證,實(shí)驗(yàn)結(jié)果證明控制策略的有效性。
[Abstract]:Microgrid composed of renewable energy, energy storage equipment and power electronic devices has gradually become an effective way to meet the demand of load growth. With the access of a large number of distributed generating units, there is a parallel operation state of multi-inverter in isolated island microgrid. The power distribution and circulation problems are easily caused by the mismatch of line impedance and local load, and the stable operation of the system is affected. Considering the influence of line impedance and local load on the power distribution and circulation of parallel systems, this paper distinguishes the connection and difference of the system under the condition of capacity distribution and zero circulation operation, and compares the line losses in the two states. Considering system efficiency, an improved droop control scheme based on average power is proposed. This scheme does not need to consider the influence of line impedance and local load on power distribution separately. The voltage offset produced by power difference is used to compensate the voltage amplitude to realize power distribution and reduce the circulation. And in the same capacity and different capacity parallel system can achieve better load distribution. In order to design the sag coefficient reasonably, the influence of voltage and current loop is often ignored, and the stability of the system is analyzed by establishing a small signal model of droop link. However, there is harmonic interaction among the distributed generation units in the isolated island system. In this paper, considering the closed-loop effect of inverter voltage and current, the relationship between the common coupling point voltage and the reference voltage and the output current in the isolated island system is derived. The equivalent Thevenin model of multi-machine droop system is established, and the stability of the system is judged by Nyquist stability criterion based on impedance. The theoretical analysis and simulation results show that the line impedance and the number of parallel inverters have important effects on the harmonic stability of the system. Finally, the parallel experiment platform of three-phase inverter based on DSP of TMS320F2812 is built and the experimental results show that the control strategy is effective.
【學(xué)位授予單位】：燕山大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TM732;TM712

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 王成山;肖朝霞;王守相;;微網(wǎng)中分布式電源逆變器的多環(huán)反饋控制策略[J];電工技術(shù)學(xué)報(bào);2009年02期

2 王成山;肖朝霞;王守相;;微網(wǎng)綜合控制與分析[J];電力系統(tǒng)自動(dòng)化;2008年07期

3 許德志;汪飛;毛華龍;阮毅;張巍;;多并網(wǎng)逆變器與電網(wǎng)的諧波交互建模與分析[J];中國電機(jī)工程學(xué)報(bào);2013年12期

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本文編號(hào)：1918067