Question
Download Solution PDFIf the speed of a 3-phase, 400 V, 50 Hz synchronous motor is tripled, the efficiency of the machine will _______.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFPower flow in the synchronous motor
The efficiency of the synchronous motor is given by:
% η \(={P_{out}\over P_{in}}\times 100\)
% η = \(={P_{in}-3I_a^2R_a-P_c\over P_{in}}\times 100\)
Explanation
The synchronous speed is given by:
\(N_s={120f\over P}\)
where, Ns = Synchronous speed
f = Frequency
P = No. of poles
The efficiency of the motor is independent of the synchronous speed, hence the efficiency of the machine will remain constant.
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