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···········································································································装订线··································································································山东建筑大学试卷共3页第1页2008至2009学年第2学期课程名称电力电子技术（专科）试卷A专业：建筑电气工程技术（专）;考试性质：闭卷;考试时间120分钟题号一二三四总分分数得分阅卷人一．填空（1×10=10分）1．处于阻断状态的晶闸管，只有在阳极，且在门极加正向触发电压时，才能使其开通。2．电压型逆变器的输出电压波形为。3．有源逆变产生的条件之一是：变流电路输出侧有直流电源，其极性为___________，且满足|Ud||Ed|。4．单相全控桥式整流大电感负载电路中，晶闸管的导通角θ=___________。5．普通晶闸管的管芯是一种大功率___________层结构的半导体元件。6．三相半波可控整流中，晶闸管控制角的起始点在_________________。7．PWM控制技术就是的技术。8．单组单相全控桥能使电动机在Ⅰ、_________象限中工作。9．三相半波可控整流电路,在电阻性负载时,当控制角α≤30°,每个晶闸管的导通角θ=________。此电路的移相范围为_______。得分阅卷人二.单项选择（1×10=10分，选出一个正确答案，并将正确答案的号码填在题后面的括号内。）1．把交流电变成直流电的是（）。A.逆变电路B.整流电路C.斩波电路D.调压电路2．升压斩波电路中，已知电源电压Ud=12V，导通比α=1/3，则负载电压U0=（）。A.4VB.18VC.36VD.8V3．单相半波可控整流电路，带电阻负载，控制角α的最大移相范围为（）。A．0°～90°B．0°～180°C．0°～120°D．0°～150°4．在GTR作为开关的电路中，若在转换的过程中出现从高电压小电流到低电压大电流的现象，则说明晶体管（）。A．失控B．不能控制开通C．不能控制关断D．二次击穿5．对于同一晶闸管,维持电流IH与擎住电流IL的关系是()。A．IL≈(2~4)IHB．IH≈(2~4)ILC．IH=ILD．IH≥IL6.锯齿波为同步信号的触发电路中，若控制电压保持不变，同步信号的周期也不变，则改变同步电压的（），即能实现移相。A.幅值B.后沿C.斜率D.前沿7．以下器件不是全控型器件的是()。A.晶闸管B.电力晶体管C.电力场效应晶体管D.绝缘栅双极晶体管8．三相全控桥式整流电路在宽脉冲触发方式下，一个周期内所需要的触发脉冲共有六个，它们在相位上依次相差（）。A.60°B.120°C.90°D.180°9．当晶闸管承受反向阳极电压时，不论门极加何种极性触发电压，管子都将工作在()。A.导通状态B.关断状态C.饱和状态D.不定10．大电感性负载的三相半波整流电路，流过晶闸管的平均电流为（）。A．dI21B．dI22C．dI31D．dI33得分阅卷人三．简答题（5×7=35分）2．什么是PWM控制技术？班级姓名学号山东建筑大学试卷共3页第2页1．交交变频电路和交直交变频电路相比有何优缺点?2．什么是直流斩波电路?举出两种基本的斩波电路形式。3．画出三相半波可控整流电路，当α=90°时的输出电压ud及晶闸管两端承受电压uT1的波形。4.全控型器件的换流方式是哪一种？晶闸管可以有哪几种换流方式？5.晶闸管关断的条件是什么？6.什么是PWM控制?7.有源逆变和无源逆变有何区别？四．计算题（45分）1.（15分）单相半波可控整流电路对电阻性负载供电，已知U2=220V，要求输出直流平均电压Ud=80V，平均电流Id=50A，试计算晶闸管的控制角α，导通角θ各为何值，并计算流过晶闸管的电流平均值和有效值。得分阅卷人···········································································································装订线··································································································山东建筑大学试卷共3页第3页2.（15分）单相桥式半控整流电路，由220V经变压器供电，负载为大电感，并接有续流二极管，要求输出整流电压20～80V连续可调，最大负载电流为20A，最小控制角αmin=3０°。试回答：(1)画出此时输出电压、电流波形；续流二极管的电流以及晶闸管承受电压的波形；(2)计算晶闸管电流有效值；(3)计算续流二极管的电流平均值。3．（15分）三相桥式全控整流电路，反电动势阻感负载，U2=100V，R=1Ω，L=∞，LB=2mH，求：当α=120°，E=-200V时Ud、Id和换相重叠角γ。···········································································································装订线·············································································································································································································装订线··································································································