【摘要】：近年來,隨著電力電子技術(shù)的不斷進步,大量電力電子設(shè)備的接入給電網(wǎng)帶來了一系列嚴重的問題。電源作為電力電子設(shè)備最重要的組成部分之一,其品質(zhì)的優(yōu)劣對用電設(shè)備的性能會產(chǎn)生很大的影響。開關(guān)電源自產(chǎn)生以來,給人們的生活帶來了很大的方便,同時也因為自身的非線性和低功率因數(shù)等特點使電網(wǎng)的諧波污染更加嚴重。APFC技術(shù)能夠減小輸入電流的諧波含量,提高開關(guān)電源的功率因數(shù),因此越來越受到人們的重視。APFC技術(shù)的研究有利于推動我國開關(guān)電源的全面市場化,以及我國的電力電子器件走向國際。本論文結(jié)合3500W電動汽車充電機項目,研究采用平均電流控制的Boost型APFC電路原理。首先對電動汽車充電機的電路結(jié)構(gòu)進行總體分析,對前級APFC的原理與后級DC/DC級的原理進行詳細地分析。分析三種常見的電流控制方式,對其特點和存在的輸出紋波和輸入諧波的問題進行研究。對于DC/DC級,采用基頻分量法對LLC諧振變換器建立小信號模型,得到小信號模型和直流增益函數(shù)。分析直流增益函數(shù)隨參數(shù)的變化情況,進一步研究諧振變換器的參數(shù)設(shè)計方法。然后對APFC主電路與控制電路進行了大量的參數(shù)計算,主電路主要是升壓電感、輸出電容、采樣電阻的計算,控制電路主要是外圍電路、電壓調(diào)節(jié)器、電流調(diào)節(jié)器的參數(shù)計算。其中外圍電路又包括前饋濾波電路、振蕩器和峰值限流電路,最后得到完整的仿真電路的參數(shù)。采用SIMetrix/SIMPLIS軟件搭建仿真電路模型并進行仿真,仿真結(jié)果達到了預設(shè)定指標,表明本文建立的模型的正確性。在初步設(shè)計參數(shù)的基礎(chǔ)上,分別對主電路與控制電路進行小信號建模,得到系統(tǒng)完整的小信號模型。以相角裕度、幅值裕度等指標為約束條件,分別選取剪切頻率與紋波增益為目標函數(shù),建立電流環(huán)和電壓環(huán)的優(yōu)化數(shù)學模型,采用遺傳算法對電壓環(huán)和電流環(huán)優(yōu)化數(shù)學模型進行求解。優(yōu)化后的電壓環(huán)與電流環(huán)在穩(wěn)定性方面有了提高,而且電流環(huán)對噪聲的抑制能力與電壓環(huán)對紋波的抑制能力都加強了。在此基礎(chǔ)上,搭建了實驗電路并進行調(diào)試,主要分析研究了APFC電路實現(xiàn)過程中出現(xiàn)的各種問題和解決方法,實驗結(jié)果表明本文設(shè)計的實驗電路輸出電壓穩(wěn)定在直流400V左右,輸入電流能夠嚴格跟蹤輸入電壓波形,提高了電路的功率因數(shù)。接著改進了主電路的拓撲結(jié)構(gòu),采用結(jié)構(gòu)簡單、升壓比高的帶抽頭電感的Boost型APFC電路,有效地解決了功率開關(guān)管的沖擊電流和二極管的結(jié)溫問題。最后,根據(jù)輸入輸出指標對后級的LLC諧振變換器的電路參數(shù)進行設(shè)計,在SIMetrix仿真軟件中搭建基于芯片UCC25600的仿真模型,驗證變換器能夠在輸出200V至500V之間有效地工作,提高了電路的效率。
[Abstract]:In recent years, with the continuous progress of power electronics technology, the access of a large number of power electronic equipment has brought a series of serious problems to the power grid. As one of the most important components of power electronic equipment, the quality of power supply will have a great impact on the performance of electrical equipment. Since the generation of switching power supply, it has brought great convenience to people's life, at the same time, because of its own nonlinear and low power factor and other characteristics, the harmonic pollution of power grid is more serious. APFC technology can reduce the harmonic content of input current. People pay more and more attention to improving the power factor of switching power supply. The research of APFC technology is beneficial to promote the overall marketization of switching power supply in our country, and the power electronic devices in our country go to the world. Based on the charger project of 3500W electric vehicle, the principle of boost APFC circuit controlled by average current is studied in this paper. Firstly, the circuit structure of electric vehicle charger is analyzed in detail, and the principle of front stage APFC and the principle of rear stage DC/DC stage are analyzed in detail. Three common current control methods are analyzed, and their characteristics and the existing problems of output ripples and input harmonics are studied. For DC/DC stage, the small signal model and DC gain function are obtained by using the fundamental frequency component method to establish a small signal model for LLC resonant converter. The variation of DC gain function with parameters is analyzed, and the parameter design method of resonant converter is further studied. Then a large number of parameters are calculated for the main circuit and control circuit of APFC. The main circuit is mainly the calculation of boost inductance, output capacitance and sampling resistance, and the control circuit is mainly the parameter calculation of peripheral circuit, voltage regulator and current regulator. The peripheral circuit includes feedforward filter circuit, oscillator and peak current limiting circuit. Finally, the parameters of the complete simulation circuit are obtained. The simulation circuit model is built and simulated by SIMetrix/SIMPLIS software, and the simulation results reach the preset index, which shows the correctness of the model established in this paper. On the basis of the preliminary design parameters, the small signal modeling of the main circuit and the control circuit is carried out respectively, and the complete small signal model of the system is obtained. Taking the phase angle margin, amplitude margin and other indexes as constraints, the optimization mathematical models of current loop and voltage loop are established by selecting shear frequency and ripple gain as objective functions, respectively. Genetic algorithm is used to solve the optimization mathematical model of voltage loop and current loop. The stability of the optimized voltage loop and current loop is improved, and the suppression ability of current loop to noise and the suppression ability of voltage loop to ripples are strengthened. On this basis, the experimental circuit is built and debugged, and the problems and solutions in the realization of APFC circuit are analyzed and studied. the experimental results show that the output voltage of the experimental circuit designed in this paper is stable at about 400V DC. The input current can strictly track the input voltage waveform and improve the power factor of the circuit. Then the topology of the main circuit is improved. The boost APFC circuit with tap inductance with simple structure and high boost ratio is used to effectively solve the problems of impulse current and diode junction temperature of the power switch. Finally, according to the input and output index, the circuit parameters of the later stage LLC resonant converter are designed, and the simulation model based on chip UCC25600 is built in the SIMetrix simulation software to verify that the converter can work effectively between 200V and 500V. The efficiency of the circuit is improved.
【學位授予單位】：山東大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TM46;U469.72

【參考文獻】

相關(guān)期刊論文 前2條

1 楊汝;平均電流模式的控制電路設(shè)計[J];電力電子技術(shù);2002年04期

2 魯芳;朱飛翔;吳青坡;;基于小信號模型的Boost-PFC控制電路優(yōu)化設(shè)計[J];現(xiàn)代電子技術(shù);2010年06期

，

本文編號：2495114