电动车(che)控(kong)制(zhi)器设计方案-12管电动车(che)控(kong)制(zhi)器改(gai)24管的(de)方法技(ji)巧-KIA MOS管
信(xin)息(xi)来源：本站 日期：2018-06-04
电(dian)(dian)(dian)动车(che)控制(zhi)(zhi)(zhi)器(qi)(qi)是电(dian)(dian)(dian)动车(che)整(zheng)车(che)中的(de)核心部(bu)分，其(qi)技术性能的(de)优劣(lie)直接影响电(dian)(dian)(dian)动车(che)的(de)正常(chang)使用(yong)。目前(qian)电(dian)(dian)(dian)动车(che)用(yong)有(you)(you)刷(shua)无(wu)刷(shua)控制(zhi)(zhi)(zhi)器(qi)(qi)普遍采用(yong)PWM方式，控制(zhi)(zhi)(zhi)器(qi)(qi)内部(bu)必(bi)须具(ju)有(you)(you)PWM发生器(qi)(qi)电(dian)(dian)(dian)路(lu)，另外还(hai)有(you)(you)电(dian)(dian)(dian)源电(dian)(dian)(dian)路(lu)、功率(lv)器(qi)(qi)件(jian)(jian)、功率(lv)器(qi)(qi)件(jian)(jian)驱动电(dian)(dian)(dian)路(lu)、控制(zhi)(zhi)(zhi)部(bu)件(jian)(jian)（转把(ba)、制(zhi)(zhi)(zhi)动把(ba)、电(dian)(dian)(dian)动机霍(huo)尔元件(jian)(jian)等）信号的(de)采集与处理(li)电(dian)(dian)(dian)路(lu)、过电(dian)(dian)(dian)流(liu)与欠电(dian)(dian)(dian)压等保护电(dian)(dian)(dian)路(lu)。
普通有刷控(kong)(kong)制(zhi)(zhi)器(qi)(qi)内(nei)部结构(gou)框(kuang)图如下图所示。电(dian)(dian)源电(dian)(dian)路(lu)为控(kong)(kong)制(zhi)(zhi)器(qi)(qi)内(nei)部电(dian)(dian)子(zi)元(yuan)器(qi)(qi)件提(ti)供工(gong)作电(dian)(dian)压(ya)(ya)(ya)；PWM芯片根(gen)据转把的输入电(dian)(dian)压(ya)(ya)(ya)输出(chu)(chu)(chu)相应脉冲宽度的方(fang)波给(ji)MOS管驱(qu)动电(dian)(dian)路(lu)；MOS管驱(qu)动电(dian)(dian)路(lu)将(jiang)PWM信号(hao)整形提(ti)供给(ji)MOS管；MOS管为大功(gong)率开(kai)关管，其导(dao)通时间(jian)与(yu)关闭时间(jian)，受导(dao)通信号(hao)与(yu)PWM信号(hao)和成(cheng)的混合信号(hao)控(kong)(kong)制(zhi)(zhi)；欠电(dian)(dian)压(ya)(ya)(ya)保(bao)护(hu)电(dian)(dian)路(lu)是(shi)当(dang)蓄电(dian)(dian)池(chi)电(dian)(dian)压(ya)(ya)(ya)降低(di)到控(kong)(kong)制(zhi)(zhi)器(qi)(qi)设定值以下时，PWM芯片停止了PWM信号(hao)输出(chu)(chu)(chu)，以保(bao)护(hu)蓄电(dian)(dian)池(chi)不至于在低(di)电(dian)(dian)压(ya)(ya)(ya)情况下放电(dian)(dian)；限电(dian)(dian)流(liu)(liu)保(bao)护(hu)（或过电(dian)(dian)流(liu)(liu)保(bao)护(hu)）电(dian)(dian)路(lu)是(shi)对(dui)控(kong)(kong)制(zhi)(zhi)器(qi)(qi)输出(chu)(chu)(chu)的最大电(dian)(dian)流(liu)(liu)进(jin)行限制(zhi)(zhi)，以保(bao)护(hu)蓄电(dian)(dian)池(chi)、控(kong)(kong)制(zhi)(zhi)器(qi)(qi)、电(dian)(dian)动机等(deng)不会出(chu)(chu)(chu)现允许范围(wei)以上的大电(dian)(dian)流(liu)(liu)。
无刷电(dian)动(dong)(dong)机控制器接线(xian)(xian)(xian)(xian)(xian)(xian)(xian)有多有少(shao)，一般有以下几条(tiao)（线(xian)(xian)(xian)(xian)(xian)(xian)(xian)的颜(yan)色(se)(se)(se)(se)(se)根据常用类型(xing)总结，不能(neng)代表所有线(xian)(xian)(xian)(xian)(xian)(xian)(xian)的颜(yan)色(se)(se)(se)(se)(se)都一样(yang)）：电(dian)源线(xian)(xian)(xian)(xian)(xian)(xian)(xian)两条(tiao)（红色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、转把线(xian)(xian)(xian)(xian)(xian)(xian)(xian)三条(tiao)（红色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、蓝(lan)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、制动(dong)(dong)断电(dian)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)两条(tiao)（黄色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、电(dian)子制动(dong)(dong)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)两条(tiao)（灰色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、电(dian)动(dong)(dong)机线(xian)(xian)(xian)(xian)(xian)(xian)(xian)两条(tiao)（绿(lv)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、蓝(lan)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、霍尔输入线(xian)(xian)(xian)(xian)(xian)(xian)(xian)四条(tiao)（蓝(lan)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、绿(lv)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、红色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、倒车(che)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)一条(tiao)（黄色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）、助(zhu)力(li)信号线(xian)(xian)(xian)(xian)(xian)(xian)(xian)三条(tiao)（红色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、绿(lv)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)、黑(hei)(hei)(hei)色(se)(se)(se)(se)(se)线(xian)(xian)(xian)(xian)(xian)(xian)(xian)）。
有刷电(dian)动机(ji)控制接线一般(ban)有以下几条(tiao)(tiao)(tiao)：电(dian)源(yuan)线两条(tiao)(tiao)(tiao)、转把线三条(tiao)(tiao)(tiao)、电(dian)动机(ji)线两条(tiao)(tiao)(tiao)、制动断电(dian)线两条(tiao)(tiao)(tiao)、限速线两条(tiao)(tiao)(tiao)等。
在电动车(che)(che)控制(zhi)器(qi)(qi)中广泛应(ying)用，方波驱动最大的(de)(de)缺点在于(yu)(yu)换(huan)相时的(de)(de)电流(liu)突变引起的(de)(de)转矩脉动，导致(zhi)噪声较(jiao)大，但好的(de)(de)控制(zhi)策略可(ke)以(yi)大大改善换(huan)相噪声。电动车(che)(che)控制(zhi)器(qi)(qi)设计的(de)(de)难点在于(yu)(yu)电流(liu)控制(zhi)，本(ben)文就电动车(che)(che)控制(zhi)器(qi)(qi)设计的(de)(de)一些(xie)关(guan)键地方加以(yi)描(miao)述。
1.概(gai)述
电(dian)(dian)(dian)动自行车上使用(yong)(yong)的(de)电(dian)(dian)(dian)机普遍采用(yong)(yong)永(yong)(yong)磁(ci)(ci)(ci)直流(liu)电(dian)(dian)(dian)机。所谓(wei)永(yong)(yong)磁(ci)(ci)(ci)电(dian)(dian)(dian)机，是指电(dian)(dian)(dian)机线圈(quan)采用(yong)(yong)永(yong)(yong)磁(ci)(ci)(ci)体(ti)激磁(ci)(ci)(ci)，不(bu)采用(yong)(yong)线圈(quan)激磁(ci)(ci)(ci)的(de)方式。这样就省去了激磁(ci)(ci)(ci)线圈(quan)工作时消(xiao)耗的(de)电(dian)(dian)(dian)能(neng)，提高了电(dian)(dian)(dian)机机电(dian)(dian)(dian)转换(huan)效率(lv)，这对使用(yong)(yong)车载(zai)有限能(neng)源的(de)电(dian)(dian)(dian)动车来讲，可以降低行驶电(dian)(dian)(dian)流(liu)，延(yan)长续行里(li)程。
永磁直(zhi)流(liu)电机(ji)(ji)(ji)(ji)按(an)照电机(ji)(ji)(ji)(ji)的通电形(xing)式来分，可分为有刷电机(ji)(ji)(ji)(ji)和无(wu)刷电机(ji)(ji)(ji)(ji)两大类，有刷电机(ji)(ji)(ji)(ji)由于采用(yong)机(ji)(ji)(ji)(ji)械换相装(zhuang)置导(dao)致可靠(kao)性和寿命降低，因此逐渐退出电动车市场。
无(wu)(wu)刷(shua)电(dian)机(ji)(ji)又(you)可分为(wei)有(you)传(chuan)(chuan)感(gan)(gan)器(qi)和无(wu)(wu)传(chuan)(chuan)感(gan)(gan)器(qi)两类(lei)，对于无(wu)(wu)位(wei)置传(chuan)(chuan)感(gan)(gan)器(qi)的(de)(de)无(wu)(wu)刷(shua)电(dian)机(ji)(ji)，必须要(yao)先将车(che)用(yong)(yong)脚蹬起来，等电(dian)机(ji)(ji)具有(you)一定的(de)(de)旋转速度以后，控(kong)制器(qi)才能识别(bie)到(dao)无(wu)(wu)刷(shua)电(dian)机(ji)(ji)的(de)(de)相位(wei)，然(ran)后控(kong)制器(qi)才能对电(dian)机(ji)(ji)供电(dian)。由(you)于无(wu)(wu)位(wei)置传(chuan)(chuan)感(gan)(gan)器(qi)无(wu)(wu)刷(shua)电(dian)机(ji)(ji)不能实现(xian)零速度启动，所以现(xian)在生产的(de)(de)电(dian)动车(che)上用(yong)(yong)得较(jiao)少。目前电(dian)动车(che)行业内(nei)使(shi)用(yong)(yong)的(de)(de)无(wu)(wu)刷(shua)电(dian)机(ji)(ji)，普遍(bian)采用(yong)(yong)有(you)位(wei)置传(chuan)(chuan)感(gan)(gan)器(qi)无(wu)(wu)刷(shua)电(dian)机(ji)(ji)。
有位置传感(gan)器永磁直流无(wu)刷(shua)电(dian)机按照内部传感(gan)器的(de)安装位置不(bu)同，又(you)可分(fen)为(wei)60度(du)电(dian)机和(he)120度(du)电(dian)机。在(zai)120°的(de)霍(huo)(huo)(huo)(huo)尔(er)信(xin)(xin)号中，不(bu)可能出(chu)(chu)(chu)现二进制000和(he)111的(de)编码，所以(yi)在(zai)一(yi)定程(cheng)度(du)上(shang)避免了(le)因(yin)霍(huo)(huo)(huo)(huo)尔(er)零(ling)件故(gu)障(zhang)而导(dao)致的(de)误(wu)操作。因(yin)为(wei)霍(huo)(huo)(huo)(huo)尔(er)组件是开漏(lou)输出(chu)(chu)(chu)，高电(dian)平依靠电(dian)路(lu)上(shang)的(de)上(shang)拉电(dian)阻提供，一(yi)旦(dan)霍(huo)(huo)(huo)(huo)尔(er)零(ling)件断(duan)电(dian)，霍(huo)(huo)(huo)(huo)尔(er)信(xin)(xin)号输出(chu)(chu)(chu)就是111.一(yi)旦(dan)霍(huo)(huo)(huo)(huo)尔(er)零(ling)件短(duan)路(lu)，霍(huo)(huo)(huo)(huo)尔(er)信(xin)(xin)号输出(chu)(chu)(chu)就是000，而60°的(de)霍(huo)(huo)(huo)(huo)尔(er)信(xin)(xin)号在(zai)正(zheng)常工作时这两种(zhong)信(xin)(xin)号均(jun)会出(chu)(chu)(chu)现，所以(yi)一(yi)定程(cheng)度(du)上(shang)影响了(le)软件判断(duan)故(gu)障(zhang)的(de)准(zhun)确率。因(yin)此(ci)目(mu)前(qian)市面马(ma)达已(yi)经逐渐舍弃60°相位的(de)霍(huo)(huo)(huo)(huo)尔(er)排列(lie)。
2.1.主回路电路
图中ABC表(biao)示(shi)电(dian)机的(de)3相(xiang)绕组(zu)，采(cai)用(yong)星形接(jie)法，V1~V6表(biao)示(shi)功率场效应(ying)管，如(ru)果将(jiang)V1~V6用(yong)如(ru)下的(de)时序波形驱动(dong)，则(ze)3相(xiang)绕组(zu)会按照AB-AC-BC-BA-CA-CB顺序通电(dian)（AB表(biao)示(shi)电(dian)流由A相(xiang)流向(xiang)B相(xiang)），产生一个旋转的(de)磁场，牵引外转子（永磁体）旋转。
导通顺序
*功(gong)能(neng)(neng)(neng)性要求：1.电(dian)子换(huan)相2.无级调速(su)3.刹车断电(dian)4.附加功(gong)能(neng)(neng)(neng)A.限速(su)B.1+1助(zhu)力C.EBS柔(rou)性电(dian)磁刹车D.定速(su)巡航(hang)E.其(qi)它功(gong)能(neng)(neng)(neng)（消除换(huan)相噪音，倒车等(deng)）
*安(an)全(quan)性要求：1.限流驱动2.过流保(bao)护3.堵(du)转保(bao)护4.电(dian)池欠(qian)压保(bao)护5.降低温(wen)升6.附加功能（防盗锁死，温(wen)升限制等）
7.附(fu)(fu)加(jia)故障检测功(gong)能从上(shang)面的(de)(de)要(yao)求(qiu)(qiu)来(lai)看，功(gong)能性(xing)(xing)要(yao)求(qiu)(qiu)和安(an)全性(xing)(xing)要(yao)求(qiu)(qiu)的(de)(de)前三项用(yong)(yong)(yong)专(zhuan)用(yong)(yong)(yong)控(kong)(kong)制芯(xin)片(pian)用(yong)(yong)(yong)加(jia)上(shang)适当的(de)(de)外围电路(lu)均(jun)不难(nan)解(jie)决，代表(biao)芯(xin)片(pian)是摩托(tuo)罗拉(la)的(de)(de)MC33035，早期的(de)(de)控(kong)(kong)制器方(fang)案均(jun)用(yong)(yong)(yong)该(gai)集成块解(jie)决。但后来(lai)随着竞争加(jia)剧，很(hen)多厂商都增(zeng)加(jia)了不少附(fu)(fu)加(jia)功(gong)能，一些(xie)附(fu)(fu)加(jia)功(gong)能用(yong)(yong)(yong)硬(ying)件(jian)来(lai)实现就比较困难(nan)，所以(yi)使用(yong)(yong)(yong)单片(pian)机来(lai)做控(kong)(kong)制的(de)(de)控(kong)(kong)制器迅速取代了纯硬(ying)件(jian)的(de)(de)专(zhuan)用(yong)(yong)(yong)控(kong)(kong)制芯(xin)片(pian)。
但(dan)是(shi)硬件(jian)控制(zhi)和软件(jian)控制(zhi)有(you)很大的(de)(de)(de)区(qu)别，硬件(jian)控制(zhi)的(de)(de)(de)反应速(su)度仅仅受(shou)限(xian)于逻辑门(men)的(de)(de)(de)开关速(su)度，而软件(jian)的(de)(de)(de)运行则需要(yao)(yao)指令执行时(shi)间(jian)。要(yao)(yao)使(shi)软件(jian)跟得上电机控制(zhi)的(de)(de)(de)需求，就(jiu)必须要(yao)(yao)求软件(jian)在最短的(de)(de)(de)时(shi)间(jian)内能够正确处理换(huan)相，电流限(xian)制(zhi)等各种复(fu)杂动作(zuo)，这就(jiu)涉及到一(yi)个对外(wai)部信号的(de)(de)(de)采(cai)样(yang)频率，采(cai)样(yang)时(shi)机，信号的(de)(de)(de)内部处理判断及处理结(jie)果的(de)(de)(de)输(shu)出(chu)，还有(you)一(yi)些(xie)抗干扰措施等，这些(xie)都是(shi)软件(jian)设计(ji)中需要(yao)(yao)仔细考(kao)虑的(de)(de)(de)东(dong)西(xi)。
在(zai)本方案中，我们(men)采用了一颗集成PWM发(fa)生器(qi)的8位(wei)单片机SH79F081，采用优化的单机器(qi)周期(qi)8051内核，内置16kFlash存(cun)储器(qi)，兼容传(chuan)统8051所(suo)有硬件(jian)资源，采用JTAG仿真(zhen)方式，内置16.6MHz振荡器(qi)，同时扩展了如下(xia)功能：*双DPTR指针。16位(wei)x8乘法(fa)器(qi)和(he)16位(wei)/8除法(fa)器(qi)。
*3通道带死区控制PWM，6路输(shu)出(chu)，输(shu)出(chu)极性可(ke)设，提供周(zhou)期溢出(chu)功(gong)能*集成故障检测功(gong)能，可(ke)瞬时关闭PWM输(shu)出(chu)。
*提供硬(ying)件抗干扰措施(shi)。
*集成高速10bitADC.*提供Flash自编程功能，可(ke)以模拟(ni)用(yong)做(zuo)EEROM，方便存储参数。
这颗(ke)IC由于CPU运行速(su)(su)度和AD采样速(su)(su)度都(dou)很快(kuai)，PWM功能强大，硬件抗干(gan)扰功能多，非常适合作电动车控(kong)制器。
4.软件实现
下面我们挑(tiao)选对控制器性能和安全比较重要的功能来讨论编程中(zhong)应(ying)该(gai)注(zhu)意的问(wen)题。
4.1.减小换相噪声(sheng)
上文已(yi)提过，无刷(shua)直流电动(dong)机(ji)方波驱动(dong)最大(da)的缺点是(shi)(shi)换相时电流不能(neng)持续，导(dao)致有转(zhuan)矩(ju)脉动(dong)，因此衡量控(kong)制(zhi)器好(hao)坏很大(da)程度上是(shi)(shi)取决于(yu)换相是(shi)(shi)否能(neng)做好(hao)。
在电(dian)(dian)(dian)动车刚刚起(qi)步的(de)(de)(de)时(shi)(shi)候我们会(hui)发(fa)现(xian)换(huan)相时(shi)(shi)电(dian)(dian)(dian)机(ji)会(hui)发(fa)出很大的(de)(de)(de)突突声，这(zhei)(zhei)是(shi)由(you)于电(dian)(dian)(dian)机(ji)起(qi)步时(shi)(shi)电(dian)(dian)(dian)流比(bi)(bi)较大，而(er)电(dian)(dian)(dian)机(ji)是(shi)个(ge)(ge)感性负载，换(huan)相后(hou)由(you)于电(dian)(dian)(dian)机(ji)线圈(quan)电(dian)(dian)(dian)流不(bu)会(hui)一下增大到换(huan)相前的(de)(de)(de)水平，这(zhei)(zhei)样就(jiu)造成换(huan)相前后(hou)电(dian)(dian)(dian)流反差非常大，从而(er)导(dao)致牵引力的(de)(de)(de)急剧变化(hua)，这(zhei)(zhei)种变化(hua)便(bian)会(hui)引起(qi)电(dian)(dian)(dian)机(ji)强(qiang)烈振(zhen)动，这(zhei)(zhei)种振(zhen)动噪(zao)声不(bu)能完(wan)全消除，但可以(yi)采取一些措施减小(xiao)噪(zao)声方法1：在换(huan)相后(hou)的(de)(de)(de)一段(duan)时(shi)(shi)间(jian)使(shi)PWM脉冲(chong)占(zhan)空比(bi)(bi)达到100%来使(shi)电(dian)(dian)(dian)流增长快一点，从而(er)减轻振(zhen)动噪(zao)声。需(xu)要(yao)提(ti)醒的(de)(de)(de)是(shi)在这(zhei)(zhei)个(ge)(ge)过程中我们需(xu)要(yao)随(sui)时(shi)(shi)监测电(dian)(dian)(dian)流变化(hua)，电(dian)(dian)(dian)流一达到换(huan)相前的(de)(de)(de)水平就(jiu)可以(yi)恢复换(huan)相前的(de)(de)(de)PWM占(zhan)空比(bi)(bi)。
方(fang)法2：延(yan)迟关(guan)(guan)闭(bi)(bi)换(huan)(huan)相(xiang)(xiang)(xiang)MOS管，方(fang)波驱动(dong)直流(liu)无(wu)刷电(dian)(dian)(dian)(dian)(dian)机是(shi)6步(bu)驱动(dong)，定(ding)(ding)子(zi)(zi)励磁(ci)每(mei)隔60度电(dian)(dian)(dian)(dian)(dian)角度跳跃(yue)一次，保证(zheng)定(ding)(ding)子(zi)(zi)磁(ci)动(dong)势(shi)方(fang)向和转(zhuan)(zhuan)子(zi)(zi)磁(ci)动(dong)势(shi)方(fang)向夹(jia)角在(zai)60°到120°之间运行，因(yin)为夹(jia)角在(zai)90°时(shi)(shi)转(zhuan)(zhuan)动(dong)力矩(ju)(ju)(ju)(ju)最大(da)，夹(jia)角为0°或180°时(shi)(shi)没有(you)转(zhuan)(zhuan)矩(ju)(ju)(ju)(ju)，现假设电(dian)(dian)(dian)(dian)(dian)机正转(zhuan)(zhuan)，AB导(dao)(dao)通(tong)要切换(huan)(huan)到AC导(dao)(dao)通(tong)，此时(shi)(shi)AB绕组(zu)通(tong)电(dian)(dian)(dian)(dian)(dian)产生(sheng)的定(ding)(ding)子(zi)(zi)磁(ci)势(shi)和转(zhuan)(zhuan)子(zi)(zi)磁(ci)势(shi)夹(jia)角为60°，如果(guo)正常切换(huan)(huan)到AC导(dao)(dao)通(tong)，则AC绕组(zu)通(tong)电(dian)(dian)(dian)(dian)(dian)后，定(ding)(ding)子(zi)(zi)磁(ci)势(shi)和转(zhuan)(zhuan)子(zi)(zi)磁(ci)势(shi)夹(jia)角变(bian)为120°，由(you)于切换(huan)(huan)到AC通(tong)电(dian)(dian)(dian)(dian)(dian)后电(dian)(dian)(dian)(dian)(dian)流(liu)要从0开(kai)始爬升，因(yin)此此时(shi)(shi)定(ding)(ding)子(zi)(zi)磁(ci)势(shi)幅值很(hen)小，导(dao)(dao)致转(zhuan)(zhuan)矩(ju)(ju)(ju)(ju)降低，但(dan)如果(guo)此时(shi)(shi)不关(guan)(guan)闭(bi)(bi)B，同时(shi)(shi)将(jiang)下桥C打开(kai)，则定(ding)(ding)子(zi)(zi)磁(ci)势(shi)和转(zhuan)(zhuan)子(zi)(zi)磁(ci)势(shi)的夹(jia)角变(bian)为90°，而(er)且由(you)于AB相(xiang)(xiang)(xiang)电(dian)(dian)(dian)(dian)(dian)流(liu)基本没有(you)变(bian)化，而(er)C相(xiang)(xiang)(xiang)电(dian)(dian)(dian)(dian)(dian)流(liu)还很(hen)小，因(yin)此换(huan)(huan)相(xiang)(xiang)(xiang)前(qian)后转(zhuan)(zhuan)矩(ju)(ju)(ju)(ju)变(bian)化很(hen)小，但(dan)要注意，等C相(xiang)(xiang)(xiang)电(dian)(dian)(dian)(dian)(dian)流(liu)爬升后要将(jiang)B相(xiang)(xiang)(xiang)关(guan)(guan)闭(bi)(bi)，否(fou)则3相(xiang)(xiang)(xiang)导(dao)(dao)通(tong)的合成力矩(ju)(ju)(ju)(ju)比2相(xiang)(xiang)(xiang)导(dao)(dao)通(tong)力矩(ju)(ju)(ju)(ju)大(da)，也会发生(sheng)转(zhuan)(zhuan)矩(ju)(ju)(ju)(ju)波动(dong)。
4.2.电子(zi)刹车：
电(dian)(dian)(dian)(dian)(dian)子(zi)刹(cha)车(che)(che)(che)其实是将(jiang)电(dian)(dian)(dian)(dian)(dian)动(dong)(dong)机(ji)当(dang)做发(fa)电(dian)(dian)(dian)(dian)(dian)机(ji)机(ji)运行，因此会(hui)产生电(dian)(dian)(dian)(dian)(dian)磁(ci)制(zhi)动(dong)(dong)转矩(ju)，检测到电(dian)(dian)(dian)(dian)(dian)子(zi)刹(cha)车(che)(che)(che)信(xin)(xin)号后，cpu将(jiang)上(shang)三路(lu)PWM关(guan)(guan)(guan)闭，将(jiang)下三路(lu)同时打开，占空(kong)(kong)比(bi)设为某一固定值，这样，电(dian)(dian)(dian)(dian)(dian)机(ji)相当(dang)于工(gong)作在发(fa)电(dian)(dian)(dian)(dian)(dian)机(ji)状态，给(ji)蓄电(dian)(dian)(dian)(dian)(dian)池充电(dian)(dian)(dian)(dian)(dian)，充电(dian)(dian)(dian)(dian)(dian)电(dian)(dian)(dian)(dian)(dian)流(liu)和(he)下三路(lu)占空(kong)(kong)比(bi)有(you)关(guan)(guan)(guan)，占空(kong)(kong)比(bi)越(yue)(yue)(yue)大(da)，则(ze)充电(dian)(dian)(dian)(dian)(dian)电(dian)(dian)(dian)(dian)(dian)流(liu)越(yue)(yue)(yue)大(da)，剎(cha)(cha)(cha)车(che)(che)(che)制(zhi)动(dong)(dong)能力(li)越(yue)(yue)(yue)强(qiang)，由(you)于目前电(dian)(dian)(dian)(dian)(dian)动(dong)(dong)车(che)(che)(che)上(shang)装配的(de)(de)电(dian)(dian)(dian)(dian)(dian)子(zi)剎(cha)(cha)(cha)车(che)(che)(che)都是开关(guan)(guan)(guan)信(xin)(xin)号，使(shi)用(yong)者无法调整剎(cha)(cha)(cha)车(che)(che)(che)力(li)矩(ju)，完全(quan)由(you)控制(zhi)器(qi)决定，不过由(you)电(dian)(dian)(dian)(dian)(dian)动(dong)(dong)机(ji)的(de)(de)特性(xing)，即使(shi)占空(kong)(kong)比(bi)固定，电(dian)(dian)(dian)(dian)(dian)子(zi)剎(cha)(cha)(cha)车(che)(che)(che)时转速(su)越(yue)(yue)(yue)高，发(fa)电(dian)(dian)(dian)(dian)(dian)机(ji)感生电(dian)(dian)(dian)(dian)(dian)压越(yue)(yue)(yue)高，回馈充电(dian)(dian)(dian)(dian)(dian)能力(li)越(yue)(yue)(yue)强(qiang)，剎(cha)(cha)(cha)车(che)(che)(che)力(li)矩(ju)越(yue)(yue)(yue)大(da)，当(dang)然，最好(hao)是装配线(xian)性(xing)剎(cha)(cha)(cha)车(che)(che)(che)传感器(qi)，使(shi)用(yong)者会(hui)更方便。
4.3.恒流驱动(dong)
电流信(xin)号(hao)经康铜丝采(cai)样之后分两路(lu)，一路(lu)送至放(fang)大(da)(da)器(qi)，一路(lu)送至比较器(qi)。放(fang)大(da)(da)器(qi)用(yong)来(lai)(lai)实(shi)时(shi)放(fang)大(da)(da)电流信(xin)号(hao)，放(fang)大(da)(da)倍数大(da)(da)约6.5倍，放(fang)大(da)(da)后的(de)信(xin)号(hao)提供给单(dan)片(pian)机进行(xing)AD采(cai)样转换，转换所(suo)得数字用(yong)来(lai)(lai)控制(zhi)电流不超过我们所(suo)允许的(de)值(zhi)。另(ling)一路(lu)信(xin)号(hao)送至比较器(qi)，当电流突(tu)然由(you)于某种(zhong)原因大(da)(da)大(da)(da)超过允许值(zhi)，比如一只MOSFET击(ji)穿或误导通时(shi)，比较器(qi)翻转送出(chu)低电平，送给79F081的(de)FLT引(yin)脚，无需单(dan)片(pian)机执行(xing)程(cheng)序(xu)，IC硬件会自动关闭PWM输出(chu)，从而保护MOSFET避免更大(da)(da)伤害。
故障现象：一辆“三安(an)”牌(pai)低速(su)电(dian)动(dong)汽车下坡时，驾驶人误断开了控(kong)制(zhi)(zhi)总电(dian)源的空气开关，致使无刷(shua)直流电(dian)动(dong)机由于超速(su)而产生的反(fan)电(dian)动(dong)势不(bu)能被电(dian)池吸收，控(kong)制(zhi)(zhi)器超压(ya)后损(sun)坏。
分析与检修：打(da)开(kai)控(kong)(kong)制(zhi)(zhi)(zhi)器察(cha)看(kan)，发现有(you)8只(zhi)功(gong)率(lv)MOS管(guan)爆裂，一只(zhi)贴(tie)片(pian)三极管(guan)8550击穿。更换损(sun)坏的元件后仍无法工作，说明故障未(wei)根除。该(gai)车(che)(che)(che)配备4只(zhi)山(shan)东“路娃”牌12V-170型（100AH）铅(qian)酸蓄电(dian)(dian)(dian)池。电(dian)(dian)(dian)动机额(e)定(ding)功(gong)率(lv)1000W，配备的控(kong)(kong)制(zhi)(zhi)(zhi)器为徐州开(kai)元电(dian)(dian)(dian)子科技有(you)限(xian)公司产品。控(kong)(kong)制(zhi)(zhi)(zhi)器内有(you)24只(zhi)TO-220封装(zhuang)的功(gong)率(lv)MOS管(guan)，工作电(dian)(dian)(dian)压(ya)为48V，限(xian)制(zhi)(zhi)(zhi)电(dian)(dian)(dian)流(liu)为59A，相(xiang)位(wei)角(jiao)(jiao)为120o，有(you)倒车(che)(che)(che)功(gong)能(neng)。笔者手头有(you)一些每只(zhi)10～15元的拆车(che)(che)(che)控(kong)(kong)制(zhi)(zhi)(zhi)器，如果能(neng)利用，则会(hui)(hui)降(jiang)低维修成(cheng)本。比较了一下，普通(tong)电(dian)(dian)(dian)动三轮(lun)车(che)(che)(che)上控(kong)(kong)制(zhi)(zhi)(zhi)器的电(dian)(dian)(dian)压(ya)、相(xiang)位(wei)角(jiao)(jiao)、倒车(che)(che)(che)和四轮(lun)车(che)(che)(che)相(xiang)同，只(zhi)是(shi)使用了12只(zhi)MOS管(guan)，限(xian)制(zhi)(zhi)(zhi)电(dian)(dian)(dian)流(liu)为28A，额(e)定(ding)功(gong)率(lv)为500W。如果将12管(guan)改成(cheng)24管(guan)，电(dian)(dian)(dian)流(liu)翻(fan)倍，功(gong)率(lv)自然不成(cheng)问题。两只(zhi)500W电(dian)(dian)(dian)动车(che)(che)(che)控(kong)(kong)制(zhi)(zhi)(zhi)器直接并联成(cheng)1000W是(shi)行不通(tong)的，因为不能(neng)保证两只(zhi)控(kong)(kong)制(zhi)(zhi)(zhi)器完全同步(bu)，必(bi)然会(hui)(hui)爆管(guan)。
第一(yi)，将两只(zhi)控制(zhi)器合成(cheng)一(yi)只(zhi)，信号及推动(dong)部分电(dian)(dian)(dian)路只(zhi)能(neng)用(yong)一(yi)个(ge)，末极功率(lv)MOS管(guan)并(bing)(bing)(bing)联(lian)使用(yong)。为避(bi)免(mian)爆管(guan)，并(bing)(bing)(bing)联(lian)上(shang)去的(de)功率(lv)MOS管(guan)与原管(guan)子参数相(xiang)(xiang)同或接近，管(guan)脚离电(dian)(dian)(dian)源滤(lv)波(bo)电(dian)(dian)(dian)容越(yue)近越(yue)好(hao)(hao)，并(bing)(bing)(bing)且(qie)最好(hao)(hao)不(bu)使用(yong)引线(xian)。要做到结(jie)合牢固、焊接简单、不(bu)用(yong)引线(xian)、工作可靠(kao)，只(zhi)有一(yi)个(ge)办法，那就(jiu)是并(bing)(bing)(bing)联(lian)上(shang)去的(de)12只(zhi)MOS管(guan)焊在控制(zhi)器电(dian)(dian)(dian)路板原12只(zhi)MOS管(guan)的(de)反面，由于正、反各12只(zhi)MOS管(guan)封装相(xiang)(xiang)同、间距相(xiang)(xiang)同，这就(jiu)实现了栅极、漏(lou)极、源极的(de)一(yi)一(yi)对(dui)应焊接。
第二，将取样电(dian)阻(zu)(zu)的限流(liu)值扩大(da)为原(yuan)来的2倍，该控制器电(dian)路板(ban)上的电(dian)流(liu)取样电(dian)阻(zu)(zu)用的是(shi)康(kang)铜(tong)丝，很(hen)容易辨别，如图1所示(shi)。原(yuan)来是(shi)2根(gen)，现在(zai)要再(zai)并接2根(gen)，让取样电(dian)阻(zu)(zu)的阻(zu)(zu)值减小一半。当(dang)然，也可以在(zai)原(yuan)康(kang)铜(tong)丝上面加锡来减小电(dian)阻(zu)(zu)，若改(gai)制时用毫欧表测量会(hui)更准确。
第三，控(kong)制(zhi)器(qi)电(dian)路板上(shang)的(de)(de)(de)电(dian)源正(zheng)(zheng)、负供电(dian)铜箔线(xian)要用(yong)(yong)焊锡(xi)堆锡(xi)法适(shi)当加(jia)(jia)粗(cu)。该板上(shang)的(de)(de)(de)两个1000μF/63V滤波电(dian)容安(an)装(zhuang)(zhuang)位只(zhi)(zhi)(zhi)装(zhuang)(zhuang)了一(yi)(yi)只(zhi)(zhi)(zhi)，正(zheng)(zheng)好再安(an)装(zhuang)(zhuang)一(yi)(yi)只(zhi)(zhi)(zhi)，加(jia)(jia)强(qiang)滤波功能。正(zheng)(zheng)、反安(an)装(zhuang)(zhuang)的(de)(de)(de)MOS管(guan)散(san)热(re)片不在同一(yi)(yi)平(ping)面上(shang)，两只(zhi)(zhi)(zhi)控(kong)制(zhi)器(qi)铝(lv)散(san)热(re)外壳要用(yong)(yong)角磨机切(qie)割(ge)开(kai)口后，一(yi)(yi)正(zheng)(zheng)、一(yi)(yi)反安(an)装(zhuang)(zhuang)，见图2。实(shi)际上(shang)，受控(kong)制(zhi)器(qi)体积的(de)(de)(de)限制(zhi)，即使24只(zhi)(zhi)(zhi)MOS管(guan)装(zhuang)(zhuang)在同一(yi)(yi)平(ping)面也装(zhuang)(zhuang)不下(xia)，电(dian)路连(lian)接也困(kun)难(nan)。两只(zhi)(zhi)(zhi)控(kong)制(zhi)器(qi)组合(he)，另一(yi)(yi)只(zhi)(zhi)(zhi)控(kong)制(zhi)器(qi)的(de)(de)(de)电(dian)路板上(shang)只(zhi)(zhi)(zhi)要MOS管(guan)和散(san)热(re)铝(lv)排。若手(shou)头(tou)有封(feng)装(zhuang)(zhuang)相同而(er)电(dian)流更大的(de)(de)(de)MOS管(guan)，比如用(yong)(yong)IRF3077（75V/210A）或(huo)IRF3077（75V/180A）等(deng)代替75NF75（75V /75A）就会(hui)省(sheng)时省(sheng)力，可以不增(zeng)加(jia)(jia)管(guan)子的(de)(de)(de)数量。
【注(zhu)意】若小功率控制器散(san)(san)热(re)(re)不(bu)够，可通过加设风扇(shan)或(huo)换大铝(lv)质外壳来提高散(san)(san)热(re)(re)能力。当然，既增(zeng)加管子(zi)的(de)数量，又加大管子(zi)的(de)参数效果会更好。
装好的(de)电(dian)(dian)(dian)(dian)动(dong)车(che)(che)控(kong)制(zhi)(zhi)(zhi)器(qi)模拟试车(che)(che)没(mei)有发现任何(he)问题，路试的(de)结果也令人(ren)满意，说明改(gai)制(zhi)(zhi)(zhi)思路可行。用霍尔库仑计观察行车(che)(che)电(dian)(dian)(dian)(dian)流：平路上(shang)最大电(dian)(dian)(dian)(dian)流为(wei)28A左右，急加速(su)和(he)爬坡(po)时电(dian)(dian)(dian)(dian)流为(wei)55A，下坡(po)滑行时电(dian)(dian)(dian)(dian)动(dong)机向蓄(xu)电(dian)(dian)(dian)(dian)池反充电(dian)(dian)(dian)(dian)电(dian)(dian)(dian)(dian)流最大为(wei)22A。在(zai)12℃气温下，连续行车(che)(che)在(zai)山(shan)区(qu)、丘陵、平原公路共50公里，手摸控(kong)制(zhi)(zhi)(zhi)器(qi)外壳(qiao)还是(shi)冷冷的(de)，说明改(gai)制(zhi)(zhi)(zhi)效果较(jiao)好。为(wei)了行车(che)(che)无(wu)后顾(gu)之忧，有些车(che)(che)友带一只备(bei)用控(kong)制(zhi)(zhi)(zhi)器(qi)是(shi)有道理的(de)，因为(wei)电(dian)(dian)(dian)(dian)动(dong)车(che)(che)蓄(xu)电(dian)(dian)(dian)(dian)池在(zai)寿命期以(yi)(yi)内突然损(sun)坏的(de)可能性很(hen)小，在(zai)不超(chao)载的(de)情况(kuang)下电(dian)(dian)(dian)(dian)动(dong)机也不易损(sun)坏，并(bing)且低速(su)电(dian)(dian)(dian)(dian)动(dong)汽车(che)(che)没(mei)空挡(dang)，控(kong)制(zhi)(zhi)(zhi)器(qi)损(sun)坏后推车(che)(che)电(dian)(dian)(dian)(dian)磁阻力(li)大，要拖(tuo)车(che)(che)前还要断开电(dian)(dian)(dian)(dian)动(dong)机的(de)三根(gen)相线(xian)，所(suo)以(yi)(yi)控(kong)制(zhi)(zhi)(zhi)器(qi)坏了很(hen)麻烦(fan)。
联系方(fang)式：邹先生（mos管厂家(jia)）
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