Hello !
We're doing a project in which we need to calculate the frequency response of an unknown impedance. We use a square wave as the input of the circuit and we can obtain, with a DAQ, the step response of both the known and the unknown impedances. We use the step response of the known impedance to get the value of the current on the circuit.
After that, we take both tension and current signals, apply the derivative with the Derivative x(t).vi, rebuild the waveform, apply FFT Spectrum Mag-Phase(with the Hanning window) to get both the magnitude and phase of the signals. We unbundle these clusters to get the arrays. Then, we rebuild the waveform (again) to calculate the harmonics with the Harmonic Distortion Analyzer.vi. After that, we select only the odd numbered harmonics and build another array with them. Then we divide the Magnitude signals of both and subtract the Phase signals. After that we plot it using a XY plot, but we're not getting the correct graphs or the ones we expected.
What are we doing wrong ? Does it have anything to do with the Hanning window or is our thought process that is wrong somewhere?
Thanks for reading !
