【正文】 ................................................ 15 PC817 光 耦簡(jiǎn)介 ............................................................................................. 16 UC3842 常用的電壓反饋電路 .................................................................................. 16 輸出電壓直接分壓作為誤差放大器的輸入 ................................................ 16 輔助電源輸出電壓分壓作為誤差放大器的輸入 ........................................ 18 采用線性光耦改變誤差放大器的輸入誤差電壓 ........................................ 19 4 總體設(shè)計(jì) .............................................................................................................................. 21 電路組成 .................................................................................................................... 21 系統(tǒng)實(shí)現(xiàn)功能 ............................................................................................................ 22 5 主電源部分設(shè)計(jì) .................................................................................................................. 23 輸入電路 ................................................................................................................... 23 目 錄 IV 輸入浪涌電流保護(hù) ............................................................................................... 23 輸入尖峰電壓保護(hù) ............................................................................................... 24 輸入濾波電路 ........................................................................................................... 25 差模干擾和共模干擾概念 ............................................................................ 25 濾除干擾信號(hào) ................................................................................................ 25 變壓器設(shè)計(jì) ............................................................................................................... 26 變壓器功能 ..................................................................................................... 26 磁芯飽和問(wèn)題 ................................................................................................. 26 變壓器設(shè)計(jì)步驟 ............................................................................................ 28 RCD 箝位電路設(shè)計(jì) .................................................................................................... 32 RCD 箝位電路意義 ......................................................................................... 32 RCD 箝位電路設(shè)計(jì)步驟 ................................................................................. 33 開(kāi) 關(guān)管選擇 ................................................................................................................ 34 輸出濾波器 ................................................................................................................ 34 6 控制電路設(shè)計(jì) ....................................................................................................................... 35 低電流調(diào)節(jié)控制電路 ................................................................................................ 35 恒流電路 .................................................................................................................... 36 充電指示電路 ............................................................................................................ 37 總結(jié) .......................................................................................................................................... 38 致謝 .......................................................................................................................................... 39 參考文獻(xiàn) .................................................................................................................................. 40 附錄 1 本設(shè)計(jì)電路原理圖 ..................................................................................................... 41 附錄 2 本設(shè)計(jì) PCB 圖 ............................................................................................................. 42 河北工程大學(xué)畢業(yè)設(shè)計(jì)說(shuō)明書(shū) 1 1 緒論 電動(dòng)車 的發(fā)展概況 電動(dòng)自行車是綠色節(jié)能的交通工具，在城市化發(fā)展的進(jìn)程中電動(dòng)自行車滿足了消費(fèi)者出行半徑增大的需求。 lithium battery charger。 電路設(shè)計(jì) 滿足客戶要求， 成本低廉 。主電源部 分采用 線性光耦改變電流型 PWM 控制集成芯片 UC3842 中誤差放大器的輸入誤差電壓，實(shí)現(xiàn)穩(wěn)壓 充電 。 電路主要包括整流濾波電路、功率變換電路、穩(wěn)壓電路 、 恒流電路，充電指示電路 ，實(shí)現(xiàn)對(duì)鋰電池分四個(gè)階段高效率安全充電。 利用開(kāi)關(guān)電源 實(shí)現(xiàn) 對(duì)鋰電池高效率充電是目前的發(fā)展趨勢(shì) 。摘 要 I 摘 要 電動(dòng)自行車是綠色節(jié)能的交通工具，在 節(jié)能環(huán)保的 發(fā)展進(jìn)程中電動(dòng)自行車滿足了消費(fèi)者出行半徑增大的需求。 另外，電動(dòng)車電瓶采用鋰電池 越來(lái)越多。 本設(shè)計(jì) 通過(guò)認(rèn)真調(diào)查鋰電池充電注意事項(xiàng)，電動(dòng)車用鋰電池充電過(guò)程和充電曲線， 綜合運(yùn)用了 反激式開(kāi)關(guān)電源技術(shù) ，對(duì) 電動(dòng)車用鋰電池充電器 做了具體設(shè)計(jì)。充電過(guò)程分微弱電流調(diào)節(jié)充電階段，恒流充電階段，恒壓充電。恒流 電路 實(shí)現(xiàn) 對(duì)鋰電池 恒流充電。 關(guān)鍵詞 ： 反激式 開(kāi)關(guān)電源 ； 鋰電池充電器 ； UC3842； 恒流充電 Abstract II Abstract Electric bike is a green energysaving means of transport, energysaving environmental protection in the process of development of electric bike to meet the consumer demand for travel radius. In addition, the electric bike battery using lithium batteries is increasing. Use of switching power supply to achieve high efficiency on the lithium battery charge is the current rechargeable lithium battery design through careful investigation note, lithium batteries for electric vehicle charging process and charge curves of the integrated use of a flyback switching power supply technology, lithium battery charger for electric vehicles to do a specific design. Circuit includes a rectifier filter circuit, power converter, voltage regulator circuit, the current circuit, the charging indicator circuit, charging in four phases of the lithium batteries safely and efficiently. Charging process prises weak charge current regulation phase, constant current charging phase, constant voltage charging. The main power to change the input error voltage of the error amplifier in Currentmode PWM control IC UC3842 to achieve voltage regulation. Constant current circuit of the constant current charging lithium batteries. Circuit design meet customer requirements, and low cost. Keywords: flyback switching power supply。 UC3842。經(jīng)過(guò) 15 年的快速發(fā)展，電動(dòng)自行車產(chǎn)業(yè)已經(jīng)進(jìn)入了成熟期，產(chǎn)品的質(zhì)量不斷提高，技術(shù)創(chuàng)新成果普遍應(yīng)用。整車企業(yè) 1000 余家、 6000 余家相關(guān)聯(lián)配套企業(yè)、 100000 家經(jīng)銷商、