Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · easy
In a balanced wye-connected system, the relationship between the line voltage VL and the phase voltage Vph is
- VL=Vph and IL= 3,Iph
- VL= 3,Vph and IL=Iph
- VL=Vph/ 3 and IL=Iph
- VL=3Vph and IL=Iph
Answer
B. VL= 3,Vph and IL=Iph
Solution
In a wye connection the line current flows through the phase, so IL=Iph. The line voltage is the phasor difference of two phase voltages 120° apart, which has magnitude 3,Vph.
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