Harmonic Distortion Analyzer Using Labview

Abstract

A total harmonic distortion analyzer calculates the total harmonic content of a sine wave with some distortion, expressed as total harmonic distortion (THD). A typical application is to determine the THD of an amplifier by using a very-low-distortion sine wave input and examining the output. By using a LabVIEW graphical programming environment it is creates a virtual instrument whose operation is validated in two different ways. On the one hand the input of the virtual instrument is obtained by synthesis of a periodic signal. The deformation of current signal with a set number of harmonics can be simulated for different amplitude, frequency and phase values of each harmonic number. After the synthesis of distorted signal, it can be viewed and analyzed the deforming regime characteristic parameters (the value of the total harmonic distortion factor, the fundamental frequency, the components level with the amplitudes of the measured harmonics)