本文選題：同步逆變器 + 并網(wǎng)逆變器�。� 參考：《華中科技大學(xué)》2015年碩士論文

【摘要】：基于可再生能源的分布式發(fā)電系統(tǒng)(Renewable Energy based Distributed Power Generation System,RE-DPGS)是開發(fā)和利用可再生能源的重要途徑,對于緩解能源危機與環(huán)境污染具有重要意義。并網(wǎng)逆變器是RE-DPGS與電網(wǎng)的能量交換接口裝置,同步逆變器(Synchronverter)是使并網(wǎng)逆變器模擬同步發(fā)電機特性,可以根據(jù)電網(wǎng)電壓頻率和幅值的變化自動調(diào)節(jié)其輸出的有功功率和無功功率,為電網(wǎng)提供支撐。本文研究同步逆變器的控制策略及其閉環(huán)參數(shù)設(shè)計。本文首先詳細推導(dǎo)了同步發(fā)電機的數(shù)學(xué)模型,接著從模擬同步發(fā)電機的角度給出了同步逆變器的控制方法,包括模擬同步發(fā)電機的慣性、頻率 有功功率下垂特性、電壓幅值 無功功率下垂特性。為了了解同步逆變器中的虛擬慣性作用,本文分析比較了虛擬慣性控制與下垂控制方法,得出虛擬慣性可以很好地提高系統(tǒng)頻率和電壓幅值穩(wěn)定性。接著對同步逆變器功率環(huán)進行小信號建模,得出其工頻小信號模型,并證明了其有功功率環(huán)和無功功率環(huán)的耦合很弱,因此其控制參數(shù)可分別獨立設(shè)計。介紹了一種根據(jù)系統(tǒng)截止頻率和相角裕度要求設(shè)計控制參數(shù)的方法,該方法在兼顧系統(tǒng)穩(wěn)定性、動態(tài)性能和對功率脈動抑制能力要求的前提下,能夠快速準確地計算出相應(yīng)的控制參數(shù)。分析了開關(guān)管死區(qū)對同步逆變器輸出電壓和并網(wǎng)電流的影響,指出同一橋臂兩只開關(guān)管的死區(qū)不同會導(dǎo)致并網(wǎng)電流中出現(xiàn)直流分量。為此,提出了一種基于虛擬電容的方法來抑制同步逆變器并網(wǎng)電流中的直流分量。為了驗證本文理論分析的準確性,在實驗室搭建了一臺三相20kW同步逆變器原理樣機。實驗結(jié)果證明了同步逆變器控制策略的有效性和本文理論分析的正確性。
[Abstract]:Renewable Energy based Distributed Power Generation system RE-DPGSbased on renewable energy is an important way to develop and utilize renewable energy, which is of great significance to alleviate energy crisis and environmental pollution. Grid-connected inverter is an energy exchange interface between RE-DPGS and power grid. Synchronous inverter synchronizes the characteristics of synchronous generator. It can automatically adjust the active power and reactive power according to the change of voltage frequency and amplitude. Provide support for the power grid. This paper studies the control strategy of synchronous inverter and its closed-loop parameter design. In this paper, the mathematical model of synchronous generator is deduced in detail, and then the control method of synchronous inverter is given from the angle of simulating synchronous generator, including the inertia of analog synchronous generator and the droop characteristic of active power. Voltage amplitude / reactive power sag characteristics. In order to understand the virtual inertia effect in synchronous inverter, this paper analyzes and compares the virtual inertial control and droop control methods, and draws the conclusion that virtual inertia can improve the stability of the frequency and voltage amplitude of the system. Then the power loop of synchronous inverter is modeled with small signal and its power frequency model is obtained. It is proved that the coupling of active power loop and reactive power loop is very weak, so its control parameters can be designed independently. This paper introduces a method to design control parameters according to the system cut-off frequency and phase angle margin. The method takes into account the stability, dynamic performance and power pulsation suppression ability of the system. The control parameters can be calculated quickly and accurately. The effect of dead time of switch on output voltage and grid-connected current of synchronous inverter is analyzed. It is pointed out that different dead-time of two switches with the same bridge arm will result in DC component in grid-connected current. Therefore, a method based on virtual capacitance is proposed to suppress the DC component in the grid-connected current of synchronous inverter. In order to verify the accuracy of the theoretical analysis, a prototype of a three-phase 20kW synchronous inverter is built in the laboratory. The experimental results show that the control strategy of synchronous inverter is effective and the theoretical analysis is correct.
【學(xué)位授予單位】：華中科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TM464

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1 黎先葵;同步逆變器的控制方法及閉環(huán)參數(shù)設(shè)計[D];華中科技大學(xué);2015年

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本文編號：1925116