Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · hard
In a balanced three-phase system with abc (positive) phase sequence, VAN=120 0° V. Find the line voltage VBC=VBN-VCN in polar form.
- 208 90° V
- 208 30° V
- 208 -90° V
- 120 -90° V
Answer
C. 208 -90° V
Solution
VBN=120 -120° and VCN=120 120°. VBC=VBN-VCN=(-60-j103.9)-(-60+j103.9)=-j207.8=207.8 -90° V.
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