【摘要】：在中小功率的LED驅(qū)動(dòng)領(lǐng)域,單級(jí)PFC反激式變換器因結(jié)構(gòu)簡(jiǎn)單,成本低廉而得到了廣泛的應(yīng)用。然而,由于這種結(jié)構(gòu)通常采用固定開(kāi)通時(shí)間的方式來(lái)實(shí)現(xiàn)PFC功能,頻率變化范圍較大,特別是在輕載時(shí)頻率很高,效率低下。同時(shí),反激式拓?fù)涫褂玫淖儔浩髟吅透边吘�圈的漏感都較大,變壓器損耗嚴(yán)重。因此研究單級(jí)PFC反激式LED驅(qū)動(dòng)的效率問(wèn)題顯得尤為重要。本文設(shè)計(jì)了一款基于準(zhǔn)諧振技術(shù)的單級(jí)PFC反激式LED驅(qū)動(dòng)芯片,并且同時(shí)設(shè)計(jì)了此類(lèi)LED驅(qū)動(dòng)常用的臨界控制模式結(jié)構(gòu)以便于兩者的對(duì)比。芯片外圍采用了原邊反饋方式,內(nèi)部主要包括谷底檢測(cè)模塊、次級(jí)電感電流過(guò)零檢測(cè)模塊、輸出電流預(yù)處理模塊、誤差放大器模塊、柵驅(qū)動(dòng)模塊以及欠壓過(guò)壓等各種保護(hù)模塊。為降低芯片本身的功耗,在保證可靠性的前提下,設(shè)計(jì)的子模塊大部分都采用了低功耗設(shè)計(jì),如減小誤差放大器的靜態(tài)功耗、合理設(shè)計(jì)過(guò)零檢測(cè)電路的放電電量、減小柵驅(qū)動(dòng)電路的動(dòng)態(tài)損耗等。由于要同時(shí)實(shí)現(xiàn)恒流、PFC以及準(zhǔn)諧振功能,而它們相互關(guān)聯(lián),因此電路在各個(gè)性能之間需要進(jìn)行折衷處理。本文分析了開(kāi)關(guān)電源中損耗的主要來(lái)源,以及現(xiàn)今一些常用的提高效率的方法,并對(duì)比了單級(jí)PFC與兩級(jí)PFC的優(yōu)缺點(diǎn)。根據(jù)設(shè)計(jì)目標(biāo)要求,完成了整體電路的結(jié)構(gòu)設(shè)計(jì)及效率的理論分析,設(shè)計(jì)并仿真了部分子模塊�；赥SMC_0.5μm BCD工藝對(duì)芯片進(jìn)行了整體仿真,在輸入電壓85~265VAC范圍內(nèi),輸出負(fù)載為12×1W情況時(shí),準(zhǔn)諧振模式下LED驅(qū)動(dòng)的平均效率為93.04%,臨界模式下LED驅(qū)動(dòng)的平均效率為87.95%,由此可見(jiàn),采用準(zhǔn)諧振技術(shù)可以有效提高單級(jí)PFC反激式LED驅(qū)動(dòng)的效率。論文還對(duì)基于準(zhǔn)諧振技術(shù)的LED驅(qū)動(dòng)在不同負(fù)載時(shí)的效率和PF進(jìn)行了仿真,得到了在設(shè)計(jì)的全電壓和全負(fù)載范圍內(nèi),LED驅(qū)動(dòng)的平均效率為92.5%,PF均超過(guò)0.9,從而驗(yàn)證了準(zhǔn)諧振技術(shù)在單級(jí)PFC LED驅(qū)動(dòng)電路中的實(shí)用性。
[Abstract]:In the field of medium and small power LED drive, single stage PFC flyback converter is widely used because of its simple structure and low cost. However, because this kind of structure usually uses the fixed opening time to realize the PFC function, the frequency variation range is large, especially in the light load, the frequency is very high and the efficiency is low. At the same time, the leakage inductance of the primary and secondary coils of the flyback topology is larger, and the transformer loss is serious. Therefore, it is very important to study the efficiency of single stage PFC flyback LED driver. In this paper, a single-stage PFC flyback LED driver chip based on quasi-resonant technique is designed, and the critical control mode structure of this kind of LED driver is also designed to facilitate the comparison between the two. The peripheral of the chip adopts the original side feedback mode, which mainly includes the bottom detection module, the secondary inductor current zero crossing detection module, the output current preprocessing module, the error amplifier module, the gate drive module and various protection modules such as undervoltage and overvoltage. In order to reduce the power consumption of the chip itself, most of the sub-modules are designed with low power consumption, such as reducing the static power consumption of the error amplifier and reasonably designing the discharge quantity of the zero-crossing detection circuit. Reduce the dynamic loss of gate drive circuit, etc. Since the constant-current, PFC and quasi-resonant functions are to be implemented simultaneously, and they are interrelated, the circuit needs to be compromised among each performance. In this paper, the main source of loss in switching power supply and some common methods to improve efficiency are analyzed, and the advantages and disadvantages of single stage PFC and two stage PFC are compared. According to the requirements of the design goal, the structure design and efficiency analysis of the whole circuit are completed, and some sub-modules are designed and simulated. The chip is simulated based on TSMC_0.5 渭 m BCD process. When the output load is 12 脳 1W, the average efficiency of LED driver is 93.04 in quasi-resonant mode and 87.95g in critical mode, which shows that, in the range of input voltage 85~265VAC and output load of 12 脳 1W, the average efficiency of LED driver is 93.04 and 87.95g respectively. Using quasi-resonance technique can effectively improve the efficiency of single-stage PFC flyback LED drive. The paper also simulates the efficiency and PF of the LED driver based on quasi-resonance technology under different loads. It is obtained that the average efficiency of LED driver is over 0.9in the range of full voltage and full load, which verifies the practicability of quasi-resonant technique in single-stage PFC LED drive circuit.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TM923.34

【共引文獻(xiàn)】

相關(guān)期刊論文 前1條

1 申中鴻;楊林;劉群興;蔣春旭;;一種基于多傳感器融合的LED 燈具智能調(diào)光系統(tǒng)[J];照明工程學(xué)報(bào);2014年02期

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1 張彥科;提高升壓型白光LED驅(qū)動(dòng)芯片效率的關(guān)鍵技術(shù)研究[D];北方工業(yè)大學(xué);2011年

2 黃啟祿;基于均勻照明的LED陣列的仿真研究與設(shè)計(jì)[D];華僑大學(xué);2011年

3 劉曉峰;我國(guó)光電照明企業(yè)成長(zhǎng)性研究[D];湖南科技大學(xué);2012年

4 韓月;白光LED用稀土離子摻雜Sr_3Bi（PO_4）_3的制備與發(fā)光性能[D];河北大學(xué);2013年

5 熊艷;基于專(zhuān)利管理地圖的江西省LED產(chǎn)業(yè)發(fā)展態(tài)勢(shì)分析[D];南昌航空大學(xué);2013年

6 宋川川;大功率LED燈芯溫度場(chǎng)測(cè)試研究[D];南京理工大學(xué);2014年

7 曾海;LED散熱設(shè)計(jì)與全方向燈光學(xué)設(shè)計(jì)[D];華僑大學(xué);2013年

8 黃章雋;C公司發(fā)展戰(zhàn)略研究[D];西南交通大學(xué);2014年

9 王巍;非成像離散多面擬合自由曲面光學(xué)器件設(shè)計(jì)及其在照明應(yīng)用中的研究[D];復(fù)旦大學(xué);2013年

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本文編號(hào)：2275181