what is cogging and crawling

Answer Posted / sukhjeet saini

When rotor bars are made to run parallel with stator , the
torque rises & falls correspondingly causing more
pulsations. This is termed as cogging in other qords
magnatic locking. This is reduced by making the rotor bars
run at an angle to the stator ie crawling in order to make
the torque uniform.

Crawling on the other hand signifies running of motor at
almost one seventh of the rated spped due to interference
of seventh harmonics.

Is This Answer Correct ?    144 Yes 43 No



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