WOLFRAM SYSTEMMODELER

SVPWM

SpaceVector Pulse Width Modulation

Wolfram Language

In[1]:=
SystemModel["Modelica.Electrical.PowerConverters.DCAC.Control.SVPWM"]
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Information

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

For a threephase system, 8 space vectors are available according to the following switching patterns:

  • 0 [0,0,0] length 0
  • 1 [1,0,0] 000°
  • 2 [1,1,0] 060°
  • 3 [0,1,0] 120°
  • 4 [0,1,1] 180°
  • 5 [0,0,1] 240°
  • 6 [1,0,1] 300°
  • 7 [1,1,1] length 0

Vector 1..6 form a hexagon, vector 0 and 7 are of length 0.

First, the space vector is limited, and the sector of the hexagon is determined where the input space vector u is located; then the angle of the space vector within this sector 0≤φ<60° is calculated.

The input space vector is averaged by u = ta*ua + tb*ub + t0*0, where ua is the space vector at the left border of the sector and ub is the space vector at the right border of the sector. If necessary, a zero length vector is applied additionally.

The relative time spans for averaging over one switching period are determined by the following equations:

  • Real part: u*cos(φ) = ub*tb*cos(60°) + ua*ta*1
  • Imag.part: u*sin(φ) = ub*tb*sin(60°)
  • ta + tb + t0 = 1

To obtain the positive fire signal, the switching time spans are distributed symmetrically: t0/4 + ta/2 + tb/2 +t0/2 + tb/2 + ta/2 + t0/4

The switching pattern of the negative fire signal is just the inverse of the positive fire signal.

Parameters (4)

samplePeriod

Value: 1 / f

Type: Time (s)

Description: Sample period of component

startTime

Value: 0

Type: Time (s)

Description: First sample time instant

f

Value:

Type: Frequency (Hz)

Description: Switching frequency

uMax

Value:

Type: Real

Description: Maximum length of space vector = half diagonal of hexagon

Outputs (2)

sampleTrigger

Type: Boolean

Description: True, if sample time instant

firstTrigger

Type: Boolean

Description: Rising edge signals first sample instant

Connectors (3)

u

Type: RealInput[2]

Description: Reference space phasor

fire_p

Type: BooleanOutput[m]

Description: positive fire signal

fire_n

Type: BooleanOutput[m]

Description: negative fire signal

Used in Components (1)

PWM

Modelica.Electrical.PowerConverters.DCAC.Control

PulseWidthModulation