power_fftscope

Fourier analysis of simulation data signals

Syntax

FFTDATA = power_fftscope(ScopeData)

FFTDATA = power_fftscope(FFTDATA)

power_fftscope(ScopeData)

power_fftscope(FFTDATA)

Description

FFTDATA = power_fftscope(ScopeData) returns the FFT results for the signal saved in the ScopeData structure-with-time.

FFTDATA = power_fftscope(FFTDATA) uses the FFTDATA structure as a template variable to modify analysis settings and signal selection, and to perform FFT analysis. The power_fftscope function ignores any user-defined FFTDATA fields that are not listed in the FFTDATA structure.

power_fftscope(ScopeData) plots the FFT analysis results for the last simulation cycle of the signal saved in the ScopeData variable.

power_fftscope(FFTDATA) plots the FFT analysis results for the signal options specified in the FFTDATA structure.

Input Arguments

ScopeData — Signal you want to perform Fourier analysis on

structure with time (default)

Signal you want to perform the Fourier analysis on, specified as a structure with time.

FFTDATA — Signal options

structure (default)

Signal options, specified as a structure with these fields:

Field	Description
time	The time vector of the simulation data signal saved in the ScopeData variable.
signals	The signals saved in the ScopeData variable.
blockName	The name of the Scope block associated with the ScopeData variable.
input	The input signal of the selected simulation data variable.
signal	The index of the selected input signal specified by the Input field.
startTime	The start time of the FFT window.
cycles	The number of cycles of the FFT window.
fundamental	The fundamental frequency of the analyzed signal.
maxFrequency	The maximum frequency evaluated by the FFT analysis.
THDmaxFrequency	The maximum frequency for the total harmonic distortion (THD) calculation. Set the value to inf to calculate the THD at the Nyquist frequency.
FFTdata	The analyzed signal (FFT window data).
THDbase	The base used to compute the THD. Set to fund to normalize the THD with respect to fundamental value. Set the THDbase to DC to normalize the THD with respect to the DC component value.
freqAxis	The type of frequency axis of the FFT analysis plot. Set to hertz to display the frequency axis in hertz. Set to harmonicorder to display the frequency axis in harmonic orders.
mag	The computed magnitude of FFT.
phase	The computed phase of FFT.
freq	The frequency vector.
THD	The computed THD for the analyzed signal. The THD calculation includes all the inter-harmonics of the selected input signal.
samplingTime	The sampling time of the selected input signal.
samplePerCycle	The number of samples per cycle of the selected input signal.
DCcomponent	The DC component value of the selected input signal.
magFundamental	The fundamental component value of the selected input signal.

Output Arguments

FFTDATA — FFT results for signal

structure

FFT results for the signal saved in the ScopeData argument, returned as a structure with these fields:

Field	Description
time	The time vector of the simulation data signal saved in the ScopeData variable.
signals	The signals saved in the ScopeData variable.
blockName	The name of the Scope block associated with the ScopeData variable.
input	The input signal of the selected simulation data variable.
signal	The index of the selected input signal specified by the Input field.
startTime	The start time of the FFT window.
cycles	The number of cycles of the FFT window.
fundamental	The fundamental frequency of the analyzed signal.
maxFrequency	The maximum frequency evaluated by the FFT analysis.
THDmaxFrequency	The maximum frequency for the total harmonic distortion (THD) calculation. Set the value to inf to calculate the THD at the Nyquist frequency.
FFTdata	The analyzed signal (FFT window data).
THDbase	The base used to compute the THD. Set to fund to normalize the THD with respect to fundamental value. Set the THDbase to DC to normalize the THD with respect to the DC component value.
freqAxis	The type of frequency axis of the FFT analysis plot. Set to hertz to display the frequency axis in hertz. Set to harmonicorder to display the frequency axis in harmonic orders.
mag	The computed magnitude of FFT.
phase	The computed phase of FFT.
freq	The frequency vector.
THD	The computed THD for the analyzed signal. The THD calculation includes all the inter-harmonics of the selected input signal.
samplingTime	The sampling time of the selected input signal.
samplePerCycle	The number of samples per cycle of the selected input signal.
DCcomponent	The DC component value of the selected input signal.
magFundamental	The fundamental component value of the selected input signal.

Version History

Introduced before R2006a