【摘要】：摘要：由傳統(tǒng)化石能源發(fā)電帶來的能源危機(jī)和環(huán)境污染問題迫在眉睫,可再生能源發(fā)電的出現(xiàn)緩和了人類的燃眉之急,其中最具發(fā)展?jié)摿Φ墓夥l(fā)電備受關(guān)注,而逆變器作為整個光伏系統(tǒng)的核心部件一直是學(xué)術(shù)界研究的焦點(diǎn)。針對光伏并網(wǎng)發(fā)電系統(tǒng)中光伏電池利用率低、并網(wǎng)電流諧波含量高等問題,改進(jìn)逆變器拓?fù)涫切兄行У慕鉀Q辦法。在已有的逆變器拓?fù)渲?級聯(lián)準(zhǔn)Z源逆變器拓?fù)渚哂袃?yōu)越的性能,它結(jié)合了級聯(lián)多電平輸出和準(zhǔn)Z源直通升壓的優(yōu)點(diǎn),能提高光伏并網(wǎng)系統(tǒng)的發(fā)電效率和并網(wǎng)電能的質(zhì)量。 論文以級聯(lián)準(zhǔn)Z源逆變器為研究對象,并將其應(yīng)用于光伏并網(wǎng)發(fā)電系統(tǒng),在分析了基于級聯(lián)準(zhǔn)Z源逆變器的光伏并網(wǎng)發(fā)電系統(tǒng)的結(jié)構(gòu)以及工作機(jī)理后,根據(jù)電路結(jié)構(gòu)以及控制目標(biāo)提出了適用于該系統(tǒng)的主從控制策略。為實(shí)現(xiàn)系統(tǒng)的可靠穩(wěn)定高效運(yùn)行,整個控制系統(tǒng)采用了多個閉環(huán)控制,包括光伏電池電壓輸入環(huán)、直流母線電壓環(huán)和并網(wǎng)電流環(huán),分別實(shí)現(xiàn)光伏電池板的最大功率點(diǎn)跟蹤、各級聯(lián)單元母線電壓的均衡和單位功率因素并網(wǎng),且在分析了各個閉環(huán)控制原理的基礎(chǔ)上對各控制環(huán)的調(diào)節(jié)器參數(shù)進(jìn)行了設(shè)計。另外,對載波移相調(diào)制(C PS-SPWM)方法進(jìn)行了改進(jìn),提出了針對于級聯(lián)準(zhǔn)Z源逆變器拓?fù)涞母倪M(jìn)型載波移相調(diào)制,使得逆變器輸出多電平波形從而提高并網(wǎng)電能質(zhì)量。 論文在MATLAB/SIMULINK環(huán)境下搭建了基于級聯(lián)準(zhǔn)Z源逆變器的光伏并網(wǎng)發(fā)電系統(tǒng)仿真模型,并對不同仿真條件下的仿真結(jié)果進(jìn)行對比分析,結(jié)果證明了論文的理論分析以及所提控制策略的正確性與有效性。圖86幅,表5個,參考文獻(xiàn)68篇。
[Abstract]:Abstract: the energy crisis and environmental pollution caused by traditional fossil energy power generation are imminent. The emergence of renewable energy power generation has alleviated the urgent needs of human beings, among which photovoltaic power generation, which has the most potential development, has attracted much attention. The inverter as the core component of the whole photovoltaic system has been the focus of academic research. To solve the problems of low utilization rate of photovoltaic cells and high harmonic content of grid-connected current in photovoltaic grid-connected generation system, improving inverter topology is an effective solution. Among the existing inverter topologies, the cascaded quasi-Z-source inverter topology has excellent performance. It combines the advantages of cascaded multilevel output and quasi-Z-source direct-pass boost, and can improve the efficiency of photovoltaic grid-connected system and the quality of grid-connected power. This paper takes the cascaded quasi-Z source inverter as the research object and applies it to the photovoltaic grid-connected generation system. After analyzing the structure and working mechanism of the photovoltaic grid-connected generation system based on the cascaded quasi-Z-source inverter. According to the circuit structure and the control target, the master-slave control strategy suitable for the system is proposed. In order to realize the reliable, stable and efficient operation of the system, the whole control system adopts several closed-loop controls, including the PV cell voltage input loop, the DC bus voltage loop and the grid-connected current loop, respectively to realize the maximum power point tracking of the photovoltaic panel. The voltage equalization and the unit power factor are connected to the grid. Based on the analysis of each closed-loop control principle, the regulator parameters of each control loop are designed. In addition, the carrier phase shift modulation (CPS-SPWM) method is improved, and an improved carrier phase shift modulation for cascaded quasi-Z-source inverter topology is proposed, which makes the inverter output multilevel waveform and improve the power quality of grid-connected power. In this paper, the simulation model of photovoltaic grid-connected generation system based on cascaded quasi-Z-source inverter is built in MATLAB / Simulink environment, and the simulation results under different simulation conditions are compared and analyzed. The results show that the theoretical analysis and the proposed control strategy are correct and effective. There are 86 pictures, 5 tables and 68 references.
【學(xué)位授予單位】：中南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TM464

【參考文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 趙清林;準(zhǔn)單級高頻鏈逆變電源控制及并網(wǎng)技術(shù)研究[D];燕山大學(xué);2006年

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本文編號：2124187