Answer / syed

Currently certain motors are designed to run on variable
frequency drives. By reducing frequency the motor speed is
also decreased. These drives control motor voltage and
current proportional to the frequency so that motor torque
is maintained at that particular speed.

Answer / vikas

As we know frequency is inversely proportional to time.if you run your AC motor with 50 hz frequency let consider
F=k/T
T=k/50
T=0.02k sec
and if frequency is 25hz
T=k/25
T=.04k sec
that means at 25hz it will take more time to complete one cycle.
thats why motor reduces its speed at 25HZ

Answer / simon

Formula for ALTERNATOR is

Fq=P*N/120
LET P=4,N=No.R.P.M 1500

SO 4*1500/120=50Hz

2*1500/120=25Hz.

Answer / 7anoter4

It works but you have to reduce also the voltage to a half.
Other way the no-load current and the iron losses will be
very large and the motor could stop or damage.

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