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发(fa)展逆变(bian)器技(ji)术(shu)是太阳能(neng)应用提出的要求，本文介绍了(le)太阳能(neng)逆变(bian)器的原(yuan)理及架构(gou)，着重介绍了(le)IGBT和MOSFET技(ji)术(shu)，实现智能(neng)控制是发(fa)展太阳能(neng)逆变(bian)器技(ji)术(shu)的关键。

太阳能对逆变器的要求

通过(guo)太(tai)阳能(neng)(neng)光伏(fu)技(ji)术将太(tai)阳辐射转换成(cheng)(cheng)(cheng)电能(neng)(neng)是(shi)现在(zai)市面上最有效也是(shi)最具(ju)发展(zhan)潜力的(de)可再生(sheng)能(neng)(neng)源技(ji)术。现在(zai)，普通太(tai)阳能(neng)(neng)光伏(fu)系统(tong)都是(shi)由许(xu)多紧密相连的(de)太(tai)阳能(neng)(neng)电池板(ban)组成(cheng)(cheng)(cheng)。这些电池板(ban)先分组串(chuan)联，再将不同(tong)的(de)串(chuan)联电池组并联起(qi)来形成(cheng)(cheng)(cheng)电池阵列。

目(mu)前我国光(guang)(guang)伏发(fa)电(dian)(dian)(dian)(dian)(dian)系(xi)(xi)统(tong)主要是(shi)直(zhi)流(liu)(liu)系(xi)(xi)统(tong)，即将太阳电(dian)(dian)(dian)(dian)(dian)池(chi)发(fa)出的(de)电(dian)(dian)(dian)(dian)(dian)能(neng)给(ji)蓄(xu)电(dian)(dian)(dian)(dian)(dian)池(chi)充电(dian)(dian)(dian)(dian)(dian)，而蓄(xu)电(dian)(dian)(dian)(dian)(dian)池(chi)直(zhi)接(jie)给(ji)负载(zai)(zai)供电(dian)(dian)(dian)(dian)(dian)，如(ru)我国西北(bei)地区使用较多(duo)的(de)太阳能(neng)户用照明系(xi)(xi)统(tong)以及(ji)远(yuan)离电(dian)(dian)(dian)(dian)(dian)网(wang)的(de)微波站(zhan)供电(dian)(dian)(dian)(dian)(dian)系(xi)(xi)统(tong)均(jun)为(wei)直(zhi)流(liu)(liu)系(xi)(xi)统(tong)。此类系(xi)(xi)统(tong)结构简单，成本低廉，但由于负载(zai)(zai)直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)压的(de)不同（如(ru)12Ｖ、24Ｖ、48Ｖ等），很难实现系(xi)(xi)统(tong)的(de)标准化和兼容性(xing)，特别(bie)是(shi)民用电(dian)(dian)(dian)(dian)(dian)力(li)，由于大多(duo)为(wei)交(jiao)流(liu)(liu)负载(zai)(zai)，以直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)力(li)供电(dian)(dian)(dian)(dian)(dian)的(de)光(guang)(guang)伏电(dian)(dian)(dian)(dian)(dian)源(yuan)很难作为(wei)商品进入市(shi)场(chang)。光(guang)(guang)伏发(fa)电(dian)(dian)(dian)(dian)(dian)最终将实现并网(wang)运(yun)行，这就必须(xu)采用成熟(shu)的(de)市(shi)场(chang)模(mo)式，今后交(jiao)流(liu)(liu)光(guang)(guang)伏发(fa)电(dian)(dian)(dian)(dian)(dian)系(xi)(xi)统(tong)必将成为(wei)光(guang)(guang)伏发(fa)电(dian)(dian)(dian)(dian)(dian)的(de)主流(liu)(liu)。

太(tai)(tai)阳(yang)(yang)能(neng)逆(ni)变器是(shi)一(yi)种功(gong)率(lv)电(dian)(dian)(dian)(dian)子电(dian)(dian)(dian)(dian)路，能(neng)把太(tai)(tai)阳(yang)(yang)能(neng)电(dian)(dian)(dian)(dian)池板的(de)(de)(de)直流(liu)电(dian)(dian)(dian)(dian)压转换为交流(liu)电(dian)(dian)(dian)(dian)压来驱动家用电(dian)(dian)(dian)(dian)器、照(zhao)明及(ji)电(dian)(dian)(dian)(dian)机工(gong)具等交流(liu)负载(zai)，是(shi)整(zheng)个(ge)太(tai)(tai)阳(yang)(yang)能(neng)发电(dian)(dian)(dian)(dian)系(xi)(xi)统(tong)的(de)(de)(de)关(guan)键组件。逆(ni)变器有两(liang)个(ge)基本功(gong)能(neng)：一(yi)方面是(shi)为完成(cheng)DC/AC转换的(de)(de)(de)电(dian)(dian)(dian)(dian)流(liu)连接到电(dian)(dian)(dian)(dian)网，另一(yi)方面是(shi)找出最(zui)佳的(de)(de)(de)操作点(dian)以优(you)化太(tai)(tai)阳(yang)(yang)能(neng)光伏(fu)(fu)系(xi)(xi)统(tong)的(de)(de)(de)效率(lv)。对于(yu)特定(ding)的(de)(de)(de)太(tai)(tai)阳(yang)(yang)光辐射、温度(du)及(ji)电(dian)(dian)(dian)(dian)池类型，太(tai)(tai)阳(yang)(yang)能(neng)光伏(fu)(fu)系(xi)(xi)统(tong)都相应有唯一(yi)的(de)(de)(de)最(zui)佳电(dian)(dian)(dian)(dian)压及(ji)电(dian)(dian)(dian)(dian)流(liu)，从而使光伏(fu)(fu)系(xi)(xi)统(tong)产(chan)生(sheng)最(zui)大的(de)(de)(de)能(neng)量。因此，在太(tai)(tai)阳(yang)(yang)能(neng)应用中对逆(ni)变器必须满足以下基本要求：

1.要求(qiu)具有较高(gao)的(de)(de)效率(lv)(lv)。由于(yu)目前太阳电(dian)池的(de)(de)价格(ge)偏高(gao)，为了最(zui)大限度地利用太阳电(dian)池，提高(gao)系统效率(lv)(lv)，必须设(she)法提高(gao)逆(ni)变器的(de)(de)效率(lv)(lv)。

2.要(yao)求(qiu)(qiu)具有较高的可(ke)靠性(xing)(xing)。目前光伏发电系(xi)统主要(yao)用(yong)于(yu)边远地区，许多电站无人值守和维护(hu)(hu)，这就要(yao)求(qiu)(qiu)逆变(bian)器具有合理的电路(lu)结构，严格(ge)的元器件筛选，并要(yao)求(qiu)(qiu)逆变(bian)器具备各种保(bao)(bao)护(hu)(hu)功能(neng)，如输入(ru)直(zhi)流极性(xing)(xing)接反保(bao)(bao)护(hu)(hu)，交流输出短(duan)路(lu)保(bao)(bao)护(hu)(hu)，过(guo)热、过(guo)载保(bao)(bao)护(hu)(hu)等(deng)。

3.要求(qiu)直(zhi)流(liu)输入电(dian)(dian)压(ya)有较(jiao)(jiao)宽的(de)(de)适(shi)应范围，由于太阳电(dian)(dian)池(chi)的(de)(de)端(duan)电(dian)(dian)压(ya)随负载和日照强度而变化(hua)(hua)，蓄电(dian)(dian)池(chi)虽然(ran)对太阳电(dian)(dian)池(chi)的(de)(de)电(dian)(dian)压(ya)具(ju)有重要作用，但(dan)由于蓄电(dian)(dian)池(chi)的(de)(de)电(dian)(dian)压(ya)随蓄电(dian)(dian)池(chi)剩余容量(liang)和内(nei)阻的(de)(de)变化(hua)(hua)而波动，特别是当蓄电(dian)(dian)池(chi)老化(hua)(hua)时其端(duan)电(dian)(dian)压(ya)的(de)(de)变化(hua)(hua)范围很大，如１２Ｖ蓄电(dian)(dian)池(chi)，其端(duan)电(dian)(dian)压(ya)可在１０Ｖ～１６Ｖ之(zhi)间变化(hua)(hua)，这(zhei)就要求(qiu)逆变器必须在较(jiao)(jiao)大的(de)(de)直(zhi)流(liu)输入电(dian)(dian)压(ya)范围内(nei)保证(zheng)正常工作，并保证(zheng)交流(liu)输出电(dian)(dian)压(ya)的(de)(de)稳定。

4.在(zai)中(zhong)(zhong)(zhong)、大(da)容(rong)量的(de)光(guang)伏发(fa)(fa)电(dian)系(xi)(xi)统(tong)中(zhong)(zhong)(zhong)，逆(ni)变(bian)电(dian)源的(de)输出(chu)应为(wei)失真度较(jiao)小的(de)正弦波(bo)。这是由于在(zai)中(zhong)(zhong)(zhong)、大(da)容(rong)量系(xi)(xi)统(tong)中(zhong)(zhong)(zhong)，若采用方波(bo)供电(dian)，则(ze)输出(chu)将含有较(jiao)多的(de)谐波(bo)分(fen)量，高(gao)次(ci)谐波(bo)将产生(sheng)附加损耗，许多光(guang)伏发(fa)(fa)电(dian)系(xi)(xi)统(tong)的(de)负载为(wei)通信或(huo)仪表设备(bei)，这些(xie)设备(bei)对电(dian)网品质(zhi)有较(jiao)高(gao)的(de)要求(qiu)，当中(zhong)(zhong)(zhong)、大(da)容(rong)量的(de)光(guang)伏发(fa)(fa)电(dian)系(xi)(xi)统(tong)并(bing)网运行时，为(wei)避免(mian)与公共(gong)电(dian)网的(de)电(dian)力污染，也要求(qiu)逆(ni)变(bian)器(qi)输出(chu)正弦波(bo)电(dian)流。

太(tai)阳能逆变器的(de)原理及架构

通常把(ba)交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)变(bian)(bian)(bian)(bian)换(huan)(huan)成直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)的(de)(de)过(guo)程(cheng)称(cheng)(cheng)之为(wei)整流(liu)(liu)，相(xiang)控整流(liu)(liu)是(shi)最常见(jian)的(de)(de)交(jiao)-直(zhi)流(liu)(liu)变(bian)(bian)(bian)(bian)换(huan)(huan)过(guo)程(cheng)；而(er)把(ba)直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)变(bian)(bian)(bian)(bian)换(huan)(huan)成交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)的(de)(de)过(guo)程(cheng)称(cheng)(cheng)之为(wei)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)，它是(shi)整流(liu)(liu)的(de)(de)逆(ni)(ni)(ni)过(guo)程(cheng)。在逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)电(dian)(dian)(dian)(dian)(dian)路中，按照负载性质的(de)(de)不同，逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)分为(wei)有(you)源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)和无源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)。如果把(ba)该电(dian)(dian)(dian)(dian)(dian)路的(de)(de)交(jiao)流(liu)(liu)侧接到交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)上，把(ba)直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)经过(guo)直(zhi)-交(jiao)流(liu)(liu)变(bian)(bian)(bian)(bian)换(huan)(huan)，逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)成与交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)同频率的(de)(de)交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)返送到电(dian)(dian)(dian)(dian)(dian)网上去(qu)，称(cheng)(cheng)作有(you)源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)。相(xiang)应的(de)(de)装置称(cheng)(cheng)为(wei)有(you)源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)器(qi)，控制(zhi)角大于(yu)90°的(de)(de)相(xiang)控整流(liu)(liu)器(qi)为(wei)常见(jian)的(de)(de)有(you)源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)器(qi)。而(er)把(ba)直(zhi)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)变(bian)(bian)(bian)(bian)换(huan)(huan)为(wei)交(jiao)流(liu)(liu)电(dian)(dian)(dian)(dian)(dian)能(neng)，直(zhi)接向非(fei)电(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)负载供电(dian)(dian)(dian)(dian)(dian)的(de)(de)电(dian)(dian)(dian)(dian)(dian)路，称(cheng)(cheng)之为(wei)无源(yuan)(yuan)(yuan)(yuan)逆(ni)(ni)(ni)变(bian)(bian)(bian)(bian)电(dian)(dian)(dian)(dian)(dian)路，又称(cheng)(cheng)为(wei)变(bian)(bian)(bian)(bian)频器(qi)。

逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)类(lei)型(xing)(xing)有它励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)、自(zi)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)、脉宽调制（PWM）型(xing)(xing)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)。其中他(ta)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)需要(yao)(yao)外部交流(liu)(liu)(liu)(liu)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)源，给晶闸管提供整(zheng)(zheng)流(liu)(liu)(liu)(liu)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)。他(ta)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)主要(yao)(yao)应用(yong)在大功率(lv)并网(wang)(wang)情(qing)况(kuang)下；对于(yu)功率(lv)低于(yu)1MW 的(de)(de)(de)(de)光伏发电(dian)(dian)(dian)(dian)系(xi)统，主要(yao)(yao)采用(yong)自(zi)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)方式。自(zi)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)不需要(yao)(yao)外部交流(liu)(liu)(liu)(liu)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)源，整(zheng)(zheng)流(liu)(liu)(liu)(liu)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)由逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)的(de)(de)(de)(de)一部分储能元(yuan)件（比(bi)如(ru)电(dian)(dian)(dian)(dian)容）来(lai)提供或(huo)者通过增加待关断整(zheng)(zheng)流(liu)(liu)(liu)(liu)阀（像(xiang)MOSFET 或(huo)IGBT）的(de)(de)(de)(de)电(dian)(dian)(dian)(dian)阻值(zhi)来(lai)实现。输出电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)被脉冲调制的(de)(de)(de)(de)自(zi)励(li)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)被称为脉冲逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)。这(zhei)种逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)通过增加周期内(nei)脉冲的(de)(de)(de)(de)切换次数(shu)，来(lai)降(jiang)低电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)、电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)的(de)(de)(de)(de)谐波含量；谐波含量与(yu)脉冲切换次数(shu)呈正比(bi)。目(mu)前，并网(wang)(wang)逆(ni)(ni)(ni)(ni)变(bian)(bian)器(qi)的(de)(de)(de)(de)输出控(kong)(kong)制模(mo)(mo)式主要(yao)(yao)有两种：电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)型(xing)(xing)控(kong)(kong)制模(mo)(mo)式和(he)电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)型(xing)(xing)控(kong)(kong)制模(mo)(mo)式。电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)型(xing)(xing)控(kong)(kong)制模(mo)(mo)式的(de)(de)(de)(de)原理(li)是(shi)以输出电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)作为受(shou)控(kong)(kong)量，系(xi)统输出和(he)电(dian)(dian)(dian)(dian)网(wang)(wang)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)同(tong)频同(tong)相(xiang)(xiang)的(de)(de)(de)(de)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)信(xin)号(hao)，整(zheng)(zheng)个(ge)系(xi)统相(xiang)(xiang)当(dang)于(yu)一个(ge)内(nei)阻很小(xiao)的(de)(de)(de)(de)受(shou)控(kong)(kong)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)源；电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)型(xing)(xing)控(kong)(kong)制模(mo)(mo)式的(de)(de)(de)(de)原理(li)则是(shi)以输出电(dian)(dian)(dian)(dian)感电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)作为受(shou)控(kong)(kong)目(mu)标(biao)，系(xi)统输出和(he)电(dian)(dian)(dian)(dian)网(wang)(wang)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)(ya)(ya)(ya)同(tong)频同(tong)相(xiang)(xiang)的(de)(de)(de)(de)电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)信(xin)号(hao)，整(zheng)(zheng)个(ge)系(xi)统相(xiang)(xiang)当(dang)于(yu)一个(ge)内(nei)阻较大的(de)(de)(de)(de)受(shou)控(kong)(kong)电(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)源。

目前，太(tai)阳能逆(ni)变(bian)器已有多种拓(tuo)(tuo)扑(pu)(pu)结构(gou)，最常见的是用于(yu)单相(xiang)的半(ban)桥、全(quan)桥和Heric（Sunways专利(li)）逆(ni)变(bian)器，以及用于(yu)三相(xiang)的六脉冲桥和中(zhong)点钳位（NPC）逆(ni)变(bian)器。太(tai)阳能逆(ni)变(bian)器的典型架(jia)构(gou)一般采用四个开关(guan)的全(quan)桥拓(tuo)(tuo)扑(pu)(pu)，如图(tu)1所(suo)示。

在(zai)图1中(zhong)(zhong)， Q1 和(he)(he)Q3被指定(ding)为高压(ya)(ya)(ya)侧(ce)IGBT，Q2 和(he)(he)Q4 则是低(di)(di)压(ya)(ya)(ya)侧(ce) IGBT。该逆变器(qi)用于(yu)在(zai)其(qi)目(mu)标(biao)(biao)(biao)市场的(de)频率(lv)和(he)(he)电压(ya)(ya)(ya)条件下，产生单(dan)相位正弦(xian)电压(ya)(ya)(ya)波(bo)形。有些逆变器(qi)用于(yu)连接净计(ji)量(liang)效(xiao)(xiao)益电网的(de)住宅安装，这就是其(qi)中(zhong)(zhong)一个目(mu)标(biao)(biao)(biao)应用市场，此项应用要求逆变器(qi)提(ti)(ti)供(gong)(gong)低(di)(di)谐波(bo)交流(liu)(liu)正弦(xian)电压(ya)(ya)(ya)，让力可注入(ru)电网中(zhong)(zhong)。 实(shi)质上，为保持谐波(bo)分(fen)量(liang)低(di)(di)和(he)(he)功率(lv)损(sun)(sun)耗(hao)最(zui)小(xiao)，逆变器(qi)的(de)高压(ya)(ya)(ya)端(duan)IGBT采用脉(mai)宽(kuan)调制(zhi)（PWM），低(di)(di)压(ya)(ya)(ya)端(duan)IGBT则以(yi)(yi)60Hz频率(lv)变换电流(liu)(liu)方(fang)向。通过让高压(ya)(ya)(ya)端(duan) IGBT使用20kHz或20kHz以(yi)(yi)上的(de)PWM频率(lv)和(he)(he)50/60Hz调制(zhi)方(fang)案(an)，输出电感L1和(he)(he)L2在(zai)实(shi)例中(zhong)(zhong)可以(yi)(yi)做得很小(xiao)，并且照样能对谐波(bo)分(fen)量(liang)进行高效(xiao)(xiao)滤(lv)波(bo)。与快(kuai)速(su)(su)和(he)(he)标(biao)(biao)(biao)准速(su)(su)度(du)的(de)平面器(qi)件相比，开关(guan)速(su)(su)度(du)为20kHz的(de)超快(kuai)速(su)(su)沟(gou)道型IGBT可以(yi)(yi)提(ti)(ti)供(gong)(gong)最(zui)低(di)(di)的(de)总(zong)导通损(sun)(sun)耗(hao)和(he)(he)开关(guan)功率(lv)损(sun)(sun)耗(hao)。同样，对于(yu)低(di)(di)压(ya)(ya)(ya)端(duan)开关(guan)电路，工作在(zai)60Hz的(de)标(biao)(biao)(biao)准速(su)(su)度(du)IGBT可以(yi)(yi)提(ti)(ti)供(gong)(gong)最(zui)低(di)(di)的(de)功率(lv)损(sun)(sun)耗(hao)。

这个设计中(zhong)的(de)(de)开关(guan)(guan)技(ji)术具(ju)有(you)如(ru)下优势：通过允(yun)许高(gao)压(ya)端(duan)(duan)(duan)(duan)和(he)低压(ya)端(duan)(duan)(duan)(duan)IGBT独立优化(hua)实(shi)现(xian)很(hen)高(gao)的(de)(de)效率；高(gao)压(ya)端(duan)(duan)(duan)(duan)、同封装的(de)(de)软恢(hui)复二极管没有(you)续流时间(jian)，从而消(xiao)除了不(bu)必要(yao)的(de)(de)开关(guan)(guan)损耗(hao)；低压(ya)端(duan)(duan)(duan)(duan)IGBT的(de)(de)开关(guan)(guan)频率只有(you)60Hz，因此导通损耗(hao)是这些IGBT的(de)(de)主(zhu)要(yao)因素；没有(you)交叉导通，因为任何时间(jian)点(dian)的(de)(de)开关(guan)(guan)都发生在(zai)对角(jiao)的(de)(de)两个器件上(shang)（Q1和(he)Q4或Q2和(he)Q3）；不(bu)存在(zai)总(zong)线直通的(de)(de)可(ke)能性(xing)，因为桥的(de)(de)同一边上(shang)的(de)(de)IGBT永远不(bu)可(ke)能以(yi)互(hu)补方(fang)式开关(guan)(guan)；跨接(jie)低压(ya)端(duan)(duan)(duan)(duan)IGBT的(de)(de)同封装、超快速、软恢(hui)复二极管经(jing)过优化(hua)可(ke)以(yi)使续流和(he)反向恢(hui)复期(qi)间(jian)的(de)(de)损耗(hao)达到最小。

mos 逆(ni)变(bian)器工作原理

1.直(zhi)流电(dian)(dian)可以通(tong)过震荡电(dian)(dian)路(lu)变(bian)为(wei)交(jiao)流电(dian)(dian)

2.得(de)(de)到的(de)(de)交(jiao)流(liu)电再通过线圈升(sheng)压（这(zhei)时得(de)(de)到的(de)(de)是方形波的(de)(de)交(jiao)流(liu)电）

3.对(dui)得(de)到的交流电(dian)进行整(zheng)流得(de)到正弦波

AC-DC就(jiu)比(bi)较简(jian)单(dan)了我(wo)们知道(dao)二极(ji)管有单(dan)向导电性(xing)可(ke)以(yi)用二极(ji)管的(de)这一(yi)特性(xing)连成一(yi)个电桥(qiao)让一(yi)端(duan)始终(zhong)是流(liu)(liu)入的(de)另(ling)一(yi)端(duan)始终(zhong)是流(liu)(liu)出的(de)这就(jiu)得到了电压正弦变化的(de)直流(liu)(liu)电 如(ru)果需要(yao)平滑的(de)直流(liu)(liu)电还需要(yao)进行整流(liu)(liu) 简(jian)单(dan)的(de)方法就(jiu)是连接一(yi)个电容

Inverter是(shi)(shi)一种DCtoAC的(de)(de)(de)变(bian)(bian)压器，它(ta)其(qi)实与Adapter是(shi)(shi)一种电(dian)(dian)压逆变(bian)(bian)的(de)(de)(de)过程(cheng)。Adapter是(shi)(shi)将(jiang)市电(dian)(dian)电(dian)(dian)网的(de)(de)(de)交流电(dian)(dian)压转(zhuan)变(bian)(bian)为稳定(ding)的(de)(de)(de)12V直(zhi)流输(shu)出，而(er)Inverter是(shi)(shi)将(jiang) Adapter输(shu)出的(de)(de)(de)12V直(zhi)流电(dian)(dian)压转(zhuan)变(bian)(bian)为高频的(de)(de)(de)高压交流电(dian)(dian)；两个(ge)部分同样(yang)都(dou)采(cai)用了目前用得比(bi)较多(duo)的(de)(de)(de)脉宽调(diao)制（PWM）技术。其(qi)核心部分都(dou)是(shi)(shi)一个(ge)PWM集 成控制器，Adapter用的(de)(de)(de)是(shi)(shi)UC3842，I

nverter则采用TL5001芯片。TL5001的(de)工(gong)作电压(ya)范围3.6～40V，其内部设有(you)一(yi)个误差放大(da)器，一(yi)个调节器、振荡器、有(you)死区控(kong)制的(de)PWM发生器、低压(ya)保护(hu)回路(lu)(lu)及(ji)短路(lu)(lu)保护(hu)回路(lu)(lu)等。

以下将对Inverter的工作原理进(jin)行简要介绍：

输入接口部分：

输 入部分有(you)3个信(xin)号(hao)，12V直流输入VIN、工(gong)作(zuo)(zuo)使(shi)能电(dian)压(ya)(ya)ENB及(ji)Panel电(dian)流控制(zhi)信(xin)号(hao)DIM。VIN由Adapter提供，ENB电(dian)压(ya)(ya)由主板(ban)(ban)上的(de)MCU 提供，其(qi)值为(wei)0或3V，当ENB=0时，Inverter不(bu)工(gong)作(zuo)(zuo)，而ENB=3V时，Inverter处于正常(chang)工(gong)作(zuo)(zuo)状(zhuang)态；而DIM电(dian)压(ya)(ya)由主板(ban)(ban)提供，其(qi)变化 范围在0～5V之间，将(jiang)不(bu)同的(de)DIM值反馈给PWM控制(zhi)器反馈端(duan)，Inverter向负载提供的(de)电(dian)流也将(jiang)不(bu)同，DIM值越小，Inverter输出的(de)电(dian)流 就越大(da)。

电压启动回路：

ENB为(wei)高电平时，输出高压去点亮Panel的背光灯灯管。

PWM控制器：

有以下几个功能组成(cheng)：内(nei)部参考(kao)电压(ya)(ya)、误(wu)差放大器(qi)、振荡器(qi)和PWM、过压(ya)(ya)保(bao)护(hu)(hu)、欠(qian)压(ya)(ya)保(bao)护(hu)(hu)、短(duan)路保(bao)护(hu)(hu)、输出晶体管。

直流变换：

由MOS开(kai)关管和储能电(dian)(dian)感组(zu)成电(dian)(dian)压(ya)变换电(dian)(dian)路，输(shu)入的(de)脉冲经(jing)过推挽放(fang)大器放(fang)大后驱(qu)动MOS管做开(kai)关动作，使(shi)得(de)(de)直(zhi)流电(dian)(dian)压(ya)对电(dian)(dian)感进行充放(fang)电(dian)(dian)，这样电(dian)(dian)感的(de)另一端就能得(de)(de)到交流电(dian)(dian)压(ya)。

LC振荡及输出回路：

保证灯(deng)管启动需要(yao)的1600V电压(ya)，并在灯(deng)管启动以后将电压(ya)降至800V。

输出电压反馈：

当负载工作时，反馈采样电压，起到稳(wen)定Inventer电压输出的作用。

其(qi)实你可(ke)以想象一(yi)(yi)下了.都有(you)那(nei)些电(dian)(dian)子元件需要(yao)正负极(ji),电(dian)(dian)阻(zu),电(dian)(dian)感一(yi)(yi)般(ban)不(bu)需要(yao).二极(ji)管一(yi)(yi)般(ban)坏的可(ke)能就是被击穿只要(yao)电(dian)(dian)压(ya)正常一(yi)(yi)般(ban)是没(mei)有(you)问题的,三极(ji)管的话是不(bu)会(hui)(hui)导(dao)通的.稳压(ya)管如(ru)(ru)果正负接反(fan)的话就会(hui)(hui)损坏了,但一(yi)(yi)般(ban)有(you)的电(dian)(dian)路加了保护(hu)就是利用二极(ji)管的单向导(dao)通来保护(hu).在就是电(dian)(dian)容(rong)了,电(dian)(dian)容(rong)里(li)有(you)正负之分的就是电(dian)(dian)解电(dian)(dian)容(rong)了, 如(ru)(ru)果正负接反(fan)严(yan)重的话其(qi)外壳发生爆裂.

主要元件二极管(guan).开(kai)关(guan)管(guan)振荡变压器.取样(yang).调宽管(guan).还有振荡回路电(dian)(dian)阻电(dian)(dian)容(rong)等(deng)参开(kai)关(guan)电(dian)(dian)路原理.

逆变器的主功率(lv)(lv)(lv)元件(jian)(jian)的选择至关重要，目前使用较(jiao)(jiao)多的功率(lv)(lv)(lv)元件(jian)(jian)有达林顿功率(lv)(lv)(lv)晶体管（BJT），功率(lv)(lv)(lv)场效(xiao)应管（MOSFET），绝(jue)缘栅(zha)晶体管（IGBT）和可关断晶闸管（GTO）等(deng)，在(zai)小容(rong)量(liang)(liang)低压系统中使用较(jiao)(jiao)多的器件(jian)(jian)为(wei)MOSFET，因为(wei)MOSFET具有较(jiao)(jiao)低的通(tong)态压降和较(jiao)(jiao)高的开关频率(lv)(lv)(lv)，在(zai)高压大(da)容(rong)量(liang)(liang)系统中一般均采(cai)用IGBT模块，这是因为(wei)MOSFET随(sui)着电压的升高其通(tong)态电阻(zu)也(ye)随(sui)之增大(da)，而IGBT在(zai)中容(rong)量(liang)(liang)系统中占有较(jiao)(jiao)大(da)的优势，而在(zai)特(te)大(da)容(rong)量(liang)(liang)（100KVA以(yi) 上）系统中，一般均采(cai)用GTO作为(wei)功率(lv)(lv)(lv)元件(jian)(jian)

大件：场效应管或IGBT、变压(ya)器(qi)、电容、二极管、比较器(qi)以及3525之类(lei)的主控。交(jiao)直交(jiao)逆变还有(you)整流(liu)滤波(bo)。

功率大小和精度(du)(du)，关系着(zhe)电路的复杂程度(du)(du)。

可以看一(yi)下手机充电器(qi)，这就是一(yi)个小(xiao)开关电源！

IGBT（绝缘栅(zha)双极晶体管(guan)）作(zuo)为新(xin)型(xing)电(dian)(dian)(dian)力半导(dao)体场控(kong)自(zi)关断(duan)器件，集功率MOSFET的(de)高(gao)(gao)速性(xing)能与双极性(xing)器件的(de)低(di)电(dian)(dian)(dian)阻(zu)于(yu)一(yi)体，具(ju)有(you)输入阻(zu)抗高(gao)(gao)，电(dian)(dian)(dian)压(ya)(ya)控(kong)制功耗低(di)，控(kong)制电(dian)(dian)(dian)路(lu)简单，耐高(gao)(gao)压(ya)(ya)，承受(shou)电(dian)(dian)(dian)流大等特性(xing)，在(zai)各种电(dian)(dian)(dian)力变换(huan)中获得(de)极广泛的(de)应用。与此同时，各大半导(dao)体生(sheng)产厂商(shang)不(bu)断(duan)开发IGBT的(de)高(gao)(gao)耐压(ya)(ya)、大电(dian)(dian)(dian)流、高(gao)(gao)速、低(di)饱(bao)和压(ya)(ya) 降、高(gao)(gao)可靠(kao)性(xing)、低(di)成本技术，主要采(cai)用1um以下制作(zuo)工艺，研制开发取得(de)一(yi)些新(xin)进(jin)展。