【单选题】
三相绕线式异步电机定子边电压降低时,最大转矩<imgwidth="50"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD19805.png">和临界转差率<imgwidth="54"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD19919.png">
【单选题】
关于三相异步电动机转子边产生的磁动势<imgwidth="50"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD30744.png">的旋转速度说法正确的是()
①
相对定子边磁动势<imgwidth="44"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD30878.png">静止
【单选题】
三相异步电动机的电流方程式<imgwidth="178"height="63"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD9292.png">实质上表达的是定转子间的磁势平衡关系。当转子边电流<imgwidth="40"height="63"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD9424.png">增大时,定子边电流<imgwidth="38"height="63"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD9540.png">________
【单选题】
一台变单相压器在高压边做空载实验求得的励磁参数和在低压边做空载实验求得的参数应()。假设<imgwidth="230"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD36321.png">.
①
大<imgwidth="50"height="54"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD36433.png">倍
②
小<imgwidth="50"height="54"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD36556.png">
【单选题】
一台三相6极电动机,每极每相槽数q=3,则定子总槽数Z1和极距<imgwidth="35"height="38"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD38712.png">分别为()
①
<imgwidth="328"height="59"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD38829.png">
②
<imgwidth="328"height="59"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD38940.png">
③
<imgwidth="328"height="59"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD39052.png">
【单选题】
关于他励直流发电机功率关系说法正确的是:()。
①
<imgwidth="235"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12038.png">
②
<imgwidth="215"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12148.png">
③
<imgwidth="247"height="60"src="http://wljy.whut.edu.cn:80/uploadfiles/word/DJYTD.files/DJYTD12260.png">
【单选题】
中性点不接地系统发生单相金属性接地故障,中性点对地电位升高为()
③
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191121/20191121094320_686.png"alt=""/>倍的相电压
④
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191121/20191121092420_760.png"alt=""/>倍的线电压
【单选题】
简单系统静态稳定判据为()。
①
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203164016_691.png"alt=""/>
②
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203165954_984.png"alt=""/>
③
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203164803_733.png"alt=""/>
【单选题】
用功率和阻抗表示的电压降落纵分量的表达式为()
①
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203165528_747.png"alt=""/>
②
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191121/20191121091121_256.png"alt=""/>
③
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203163709_881.png"alt=""/>
④
<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191203/20191203164836_949.png"alt=""/>
【单选题】
在电力系统潮流计算中,PV节点的待求量是()
①
Q、<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191205/20191205080031_752.png"alt=""/>
③
V、<imgsrc="http://wljy.whut.edu.cn:80/uploadfiles/kindeditorAttached/image/20191205/20191205080043_336.png"alt=""/>