WOLFRAM SYSTEM MODELER
SVPWMSpaceVector Pulse Width Modulation |
SystemModel["Modelica.Electrical.PowerConverters.DCAC.Control.SVPWM"]
This information is part of the Modelica Standard Library maintained by the Modelica Association.
For a three-phase system, 8 space vectors are available according to the following switching patterns:
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:
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.
samplePeriod |
Value: 1 / f Type: Time (s) Description: Sample period of component |
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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 |
sampleTrigger |
Type: Boolean Description: True, if sample time instant |
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firstTrigger |
Type: Boolean Description: Rising edge signals first sample instant |
u |
Type: RealInput[2] Description: Reference space phasor |
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fire_p |
Type: BooleanOutput[m] Description: Positive fire signal |
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fire_n |
Type: BooleanOutput[m] Description: Negative fire signal |
Modelica.Electrical.PowerConverters.DCAC.Control PulseWidthModulation |