Feb 05, 2015 - 06:45 AM
Any Discretized Fourier Transform method would give only the integer order harmonics.
For you to get (66 Hz, 72 Hz, 78 Hz), the only way I can see is to set the FFT at 6Hz set the harmonic numbers to 256 and use the anti-aliasing filter.
Note: this requires a longer steady state run for the FFT to work properly.
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