Spin-up Problems 3-17 & 3-18

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lizzy

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The calculation results to problems 3-17 & 3-18 seem incorrect. I think the solution should be as follows:

Problem 3-17:

IN = - (IA + IB + IC)

= - (54.8 <(0 – 36.9⁰) + 0.25<(120⁰-5⁰) + 96<(240⁰-36.8⁰))

= -(-44.52 - j70.49)

= 44.52 + j70.49

= 83.37 <57.73⁰

Problem 3-18:

IN = - (IB + IC)

= - (0.25<(120⁰-5⁰) + 96<(240⁰-36.8⁰))

= -(-88.34 – j37.59)

= 88.34 + j37.59

= 96 <23.05⁰

Also why has a phase sequence of CBA been assumed in the above two problems?

Any suggestions?

 
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