Impact of variable frequency pump speed on the motor and frequency conversion
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We have a pump that is a variable-frequency pump; what impact does it have on the variable frequency system or the pump if it doesn’t operate at its rated speed for an extended period of time? Some in our electrical engineering field say that in variable-frequency pumps, when there is no rotation speed, the alternating current is converted into direct current; this results in the highest resistance and increased heat generation in the motor. Therefore, we generally require that after the variable-frequency pump stops operating, it should not have zero rotation speed – usually, a rotation speed of 10% is maintained. Do you agree with this view?
I’ve never heard of such a claim before
I’ve never heard of that; after the pump is stopped, the power consumption should be at its lowest
Can’t we just cut off the power right after stopping the pump?
It seems there is still some difference regarding inverters
I’ve never heard of such a claim before
:) The key question is: when this variable-frequency pump stops, does the motor stop immediately, or does its frequency drop to 0?； It’s better to listen to professionals. Also, is this motor an inverter-driven motor, or a regular motor with an inverter? Different treatment is needed.
It is not allowed for the inverter to remain in a startup state with an output of 0; it’s sufficient to simply stop the pump. An output of at least 10 Hz is reasonable
I think they’re worried that no signal will be sent, the motor won’t stop, and the motor will turn into a generator.