TMS320F28069F: motorware: Volts/Hertz profile (VS_FREQ) module

Hello,

I have a question on the Volts/Hertz profile (VS_FREQ) module routines in Motorware.

The function of VS_FREQ_setProfile() in the file of vs_freq.c contains the following codes:

  obj->Vdq_gain.value[0] = _IQ(0.3);
  obj->Vdq_gain.value[1] = _IQsqrt(_IQ(obj->maxVsMag_pu*obj->maxVsMag_pu) - _IQmpy(obj->Vdq_gain.value[0], obj->Vdq_gain.value[0]));

And the function of VS_FREQ_run() in the file of vs_freq.h contains the following codes:

  obj->Vdq_out.value[0] = _IQmpy(obj->Vs_out, obj->Vdq_gain.value[0]);
  obj->Vdq_out.value[1] = _IQmpy(obj->Vs_out, obj->Vdq_gain.value[1]);

Therefore it can be written in the plain equations as follows:

Vd=0.3*Vs_out

Vq=0.4*Vs_out   for maxVsMag_pu=0.5

What are the theoretical background for the above-written equations?

Vd is given as 0.3*Vs_out.

Can it be given as 0.2*Vs_out? In that case, Vq=0.458*Vs_out evidently for maxVsMag_pu=0.5.

What is the difference in the scope of motor rotation?

Thank you for your guidance.

With regards,

JS Yoo