Custom Power Stage
3-phase Custom Power Stage
Library
GMCLIB
Description
Performs a Custom Power Stage model taking into account dead-time effect, transistor parasitic capacitance and transistor voltage drop. All these effects are specified by measured characteristic of real power stage with fixed dead-time length, PWM frequency and other parameters. The output error value is then assigned according to this characteristic. The example characteristic is shown on the following picture and represents a voltage error (which is subtracted from the output voltage) dependecy on measured current through the motor winding.
Dead-time effect for a sine wave is shown on the following picture. Dead-time is presented by voltage error added to the sine wave. The step change occurs when output current crosses zero (changes its direction).
Parameters and dialog box
The Custom Power Stage block dialog box appears as follows:
Current Look up - x-coordinate (current) of the measured characteristic [A]
Error Look up - y-coordinate (voltage) of the measured characteristic [V]
Nr. of points used to approximate the linear (left and right) parts of the characteristic [-]
Inputs and outputs
Inputs:
U in - vector of duty cycles for 3 phases (e.g. from SVM (range 0-1))
I in - vector of measured 3-phase current [A]
U DCbus - DCbus voltage (not scaled) [V]
Outputs:
U out - 3-phase output voltage (dedicated as input to a motor) [V]