Hello everyone, I am using this VFD to drive a motor connected via a long cable. I encountered severe overvoltage caused by reflected waves, so I installed a du/dt filter.
While the voltage spikes at the motor terminals have been significantly reduced, the filter itself runs very hot—it is scorching to the touch—and triggers a filter overheat alarm after just a few hours of operation.
I measured the voltage waveforms before and after the filter and found significant losses in the internal inductors and capacitors; the losses increase with the carrier frequency.
Lowering the carrier frequency reduces the temperature, but the motor noise increases.
I would like to ask: how are losses calculated when selecting a du/dt filter? Is forced-air cooling required? Or must I switch to a sine wave filter?
Thanks.
While the voltage spikes at the motor terminals have been significantly reduced, the filter itself runs very hot—it is scorching to the touch—and triggers a filter overheat alarm after just a few hours of operation.
I measured the voltage waveforms before and after the filter and found significant losses in the internal inductors and capacitors; the losses increase with the carrier frequency.
Lowering the carrier frequency reduces the temperature, but the motor noise increases.
I would like to ask: how are losses calculated when selecting a du/dt filter? Is forced-air cooling required? Or must I switch to a sine wave filter?
Thanks.