WOLFRAM SYSTEMMODELER

TotalHarmonicDistortion

Calculation of total harmonic distortion of voltage

Diagram

Wolfram Language

In[1]:=
SystemModel["Modelica.Blocks.Examples.TotalHarmonicDistortion"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

This example compares the result of the total harmonic distortion (THD) with respect to the fundamental wave and with respect to the total root mean square (RMS). In this simulation model a non-sinusoidal voltage wave form is created by the superposition two voltage waves:

  • Fundamental wave with RMS voltage V1 and frequency f1
  • Third harmonic wave with RMS voltage V3 and frequency 3*f1

This simulation model compares numerically determined THD values with results, obtained by theoretical calculations:

  • Compare the numerically determined THD value thd1.y and the theoretical value THD1, both with respect to the fundamental wave; also plot thd1.valid
  • Compare the numerically determined THD value thdRMS.y and the theoretical value THDrms, both with respect to the RMS value; also plot thdRMS.valid

Parameters (5)

f1

Value: 50

Type: Frequency (Hz)

Description: Fundamental wave frequency

V1

Value: 100

Type: Voltage (V)

Description: Fundamental wave RMS voltage

V3

Value: 20

Type: Voltage (V)

Description: Third harmonic wave RMS voltage

THD1

Value: V3 / V1

Type: Real

Description: Theoretically obtained THD with respect to fundamental wave

THDrms

Value: V3 / sqrt(V1 ^ 2 + V3 ^ 2)

Type: Real

Description: Theoretically obtained THD with respect to RMS

Components (6)

ground

Type: Ground

sineVoltage3

Type: SineVoltage

sineVoltage1

Type: SineVoltage

voltageSensor

Type: VoltageSensor

thd1

Type: TotalHarmonicDistortion

thdRMS

Type: TotalHarmonicDistortion