ThreePhaseTwoLevel_PWM

Test of pulse width modulation methods

Diagram

Information

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

A reference space vector (formed by real part = cosine and imaginary part = sine) of length √2*RMS and frequency 2 Hz is applied. The resulting switching patterns are applied to a three-phase twolevel bridge with switching frequency 100 Hz, fed by DC voltage = √2*√3*1 where 1 is the theoretical maximum voltage from terminal to neutral. The resulting voltages with reference to midpoint of the DC voltage are measured.

The RMS of the first harmonic of the first of these voltages is calculated. Please note that the value of the first harmonic is valid after the first period (i.e. 0.5 s).

Furthermore, these three voltages are transformed to the corresponding space phasor. Note that the zero component is not zero, indicating the shift of the neutral with respect to the midpoint of the DC voltage.

The space phasor is rotated to the coordinate system rotating with 2*π*2 Hz. To suppress the influence of switching, real and imaginary part of the rotated phasor are filtered. The polar representation of this rotated and filtered phasor are calculated.

Please note that the filter has a settle time depending on the filter parameters.

Parameters (1)

RMS

Value: 1

Type: Real

Description: Reference RMS Y

Components (15)

cosine

Type: Cosine

sine

Type: Sine

pwm

Type: PWM

multiPhase2Level

Type: Polyphase2Level

dcPos

Type: ConstantVoltage

dcNeg

Type: ConstantVoltage

ground

Type: Ground

potentialSensor

Type: PotentialSensor

harmonic

Type: Harmonic

toSpacePhasor

Type: ToSpacePhasor

rotator

Type: Rotator

const

Type: Constant

integrator

Type: Integrator

filter

Type: Filter[2]

toPolar

Type: ToPolar