Electrical Engineering (EE) Exam  >  Electrical Engineering (EE) Questions  >  A 4-pole induction motor, supplied by a sligh... Start Learning for Free
A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hz source, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor is 
  • a)
    100
  • b)
    98
  • c)
    52
  • d)
    48
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
A 4-pole induction motor, supplied by a slightly unbalanced three-phas...
View all questions of this test
Most Upvoted Answer
A 4-pole induction motor, supplied by a slightly unbalanced three-phas...
Given Data:
Number of poles (P) = 4
Supply Frequency (f) = 50 Hz
Rotor Speed (N) = 1440 rpm

To find: Electrical frequency of the induced negative sequence current in the rotor.

Formula Used:
Synchronous Speed (Ns) = 120*f/P
Rotor Speed (N) = (1-s)*Ns [where s is the slip]

Explanation:
The synchronous speed of the given motor can be calculated by using the above formula as,

Ns = 120*50/4 = 1500 rpm

The slip (s) of the motor can be calculated as,

s = (Ns - N)/Ns = (1500 - 1440)/1500 = 0.04

The electrical frequency of the induced negative sequence current in the rotor can be given by,

fe = s*f = 0.04*50 = 2 Hz

However, the negative sequence current is rotating in the opposite direction of the rotor. Hence, the electrical frequency of the negative sequence current in the rotor can be given by,

f_neg_seq = f - fe = 50 - 2 = 48 Hz

Therefore, the correct option is (b) 98 Hz.

Note: The electrical frequency of the negative sequence current is always equal to the supply frequency minus twice the slip frequency.
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer?
Question Description
A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer?.
Solutions for A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electrical Engineering (EE). Download more important topics, notes, lectures and mock test series for Electrical Engineering (EE) Exam by signing up for free.
Here you can find the meaning of A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer?, a detailed solution for A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50Hzsource, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor isa)100b)98c)52d)48Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice Electrical Engineering (EE) tests.
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev