【简答题】例2:电路如图所示,加在三角形连接负载上的三相电压对称,其线电压为380V,三相对称负载阻抗Z=17.3+10jΩ时,试求:(1)各相电流和中线电流。 (2)BC相负载断开后的各相电流和线电流。
【单选题】"...Plenty of people of all generations still view a BA as a prerequisite of success in life. But Dew says older people “get stuck“ on the fact that he has no intention of getting a bachelor's degree....
B.
To have a new idea with merit
【单选题】题5图所示三相电路中,电源线电压为380 V,三相负载均由“60W,220V”的白炽 灯泡组成,其中:U相有 3 盏,V相有 2 盏,W 相有 1 盏。若电路出现断路故障, 断路点如图中记号“×”所示,则各相所接灯泡亮度的变化情况分别为( )。
C.
U相灯泡亮度不变,V相灯泡变暗,W相灯泡变亮
D.
U相灯泡亮度不变,V相灯泡变亮,W相灯泡变暗
【单选题】"...Plenty of people of all generations still view a BA as a prerequisite of success in life. But Dew says older people “get stuck“ on the fact that he has no intention of getting a bachelor's degree....
B.
To have a new idea with merit
【单选题】频率为 25 帧 / 秒的制式为( )制。
【简答题】题5.2.5图所示的是三相四线制电路,电源线电压U1=380V。三个电阻性负载接成星形,其电阻为R1=11Ω,R2=R3=22Ω。(1)试求负载相电压、相电流及中性线电流,并作出它们的相量图;(2)如无中性线,求负载相电压及中性点电压;(3)如无中性线,当L,相短路时求各相电压和电流,并作出它们的相量图;(4)如无中性线,当L3相断路时求另外两相的电压和电流;(5)在(3)、(4)中如有中性线,则...
【多选题】细菌芽孢在100°C水中加热8h仍有活性残留,关于芽孢耐热的原因以下叙述正确的是( )。