Thread: How do I use Matlab to find the harmonics of a waveform?

I have a Simulink model, and I want to find the components of a current signal in my model. I have a current measuring block, and I can output the signal to a variable.

How do I find the magnitude of the harmonics in my waveform?

I'm not sure exactly what you want, but I'd suggest doing a FFT on the data if you have current as a function of time. You've got to have good enough time resolution for this, and the data set has to be in powers of two (128, 256, 512, etc). This will allow you to decompose the data into it's frequency components, and you can get the power spectrum for this. (If you do this for instrumentation signals and get a big peak at 60 hz, you know you have poor shielding).

This allows you to turn a time signal into its frequency components. Is this what you want?

Try a data set in excel first (there is a FFT function in an addon), then figure it out in simulink. Shouldn't be too hard to implement.