• 2022-06-03
    负序对称三相电源作星形联结,其中C相电源相电压uC=Umcos(ωt-90°)V,则B相电源相电压为( )。
    A: uB=Umcos(ωt-150°)V
    B: uB=Umcos(ωt+150°)V
    C: uB=Umcos(ωt+30°)V
    D: uB=Umcos(ωt-30°)V