Sr. No

Power Quality Analysis Techniques




Short Time Fourier Transform

It’s simple in implementation; it is used in stationary signals successfully whose properties do not change in time.

It has a fixed window width limitation which does not follow signals dynamics appropriately therefore it’s not suitable for non stationary signals.


Hilbert Huang Transform

Phase and instantaneous amplitude can be simply assessed due it generation of quadrature signals. It’s very useful in distorted waveforms to extraction of features.

It used to works only in narrow band conditions which is very limited.



It’s very flexible it can easily convertible in 2-D frequency translation domain from time domain and even to Fourier frequency domain.

The reliance of frequency window width on central frequency generates inaccurate measurements of harmonics. It also does not gratify real-time necessities subject to block processing manner.


Wavelet Transform

It is suitable in an excellent time-frequency resolution it also provides in time as well as frequency the local representation.

It’s anguishing due to the picket fence effect and spectral leakage and also sturdily affected due to presence of noises in the signal.


Gabor-Wigner Transform

It has good time-frequency resolution as well as high signal to noise ratio.

The time computational span is on high complexity as it’s directly associated to sampling frequency. As well as it has a very limited availability at high frequencies.