Question

A symmetrical star connected system has VRN = 230∠0⁰. The phase sequence is RYB. Find VBR. (a) 398.37∠210⁰ (b) 398.37∠-210⁰ (c) 398.37∠120⁰ (d) 398.37∠-120⁰ The question was posed to me during a job interview. My question is taken from Voltage, Current and Power in a Star Connected System in chapter Polyphase Circuits of Network Theory Select the correct answer from above options network theory questions and answers, network theory questions pdf, network theory question bank, network theory gate questions and answers pdf, mcq on network theory pdf, gate network theory questions and solutions, network theory mcq Test , ies network theory questions, Network theory Questions for GATE EC Exam, Network Theory MCQ (Multiple Choice Questions)

Answer 1

The correct answer is (b) 398.37∠-210⁰ The best I can explain: All the line voltages are equal in magnitude and are displaced by 120⁰. VBN = 230∠-240⁰V. VBR = √3×230∠(-240^o+30^o)V=398.37∠-210^oV.