Variable Frequency Drive for ATmega328 based Arduinos - GitHub - carneeki/OpenVFD: Variable Frequency Drive for ATmega328 based Arduinos
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How to add constant VF option please if the motor is rated 230V, 50Hz?
I know that I need to scale the values in the lookup table, but how?
Another question, if I change the PWM carrier frequency from 31kHz to 8kHz, Have I to use another lookup table? How to generate it?
Many thanks in advance.
to filter SPWM pulses at the final stage as dependent on load and frequency. It may be necessary for you to test different LC values (in the 2nd-order low-pass filter) in order discover what circumstances require which values (and/or L:C ratio).
Thanks Bradtherad for your contribution in the thread.
The inherent LR filter load representing the motor will "convert" the SPWM into a pure sinodal electric signal.
the motor acts as a low pass filter. The inductance and resistance of the coils windings create a low pass RL filter. Further, the inertia of the rotor and load creates a mechanical low pass filter.
A VFD however can't run with constant V/F above rated motor frequency without either using a higher input respectively DC link voltage or rewiring the motor from wye to delta (if not already delta wired).