We are using the following functions to get the values for estimated torque and estimated flux and the values returned do not appear to be correct.
EST_getTorque_Nm ()
EST_getFlux_Wb ()
The values for torque are very low; for example, when slowing the motor with a hand controlled friction, the torque values are approximately 0.0001 – 0.0002 Newton-meters.
The values for flux are consistently 0.0
The motor runs smoothly.
Test configuration is:
AC Induction Motor
Modified DRV8301 board. The modified version does not use the 8301 chip.
Custom inverter hardware
An encoder is used to provide input to get speed and angle information
TMS320-F28069MPZT
Motorware 14 Lab 4 is the basis for the software which has been modified to support the changed hardware.
The custom hardware does not supply voltage levels to the ADCs and the values of the voltage input are set to 0:
pAdcData->V.value[0] = 0;
pAdcData->V.value[1] = 0;
pAdcData->V.value[2] = 0;
Questions:
(1) Are the functions EST_getTorque_Nm and EST_getFlux_Wb the correct functions to call to get torque and flux?
(2) What are the units returned by EST_getTorque_Nm? Currently using the milli-Newton-meter units identified in the following post:
“You should use the EST_getTorque_Nm() function call to get torque information from InstaSPIN-FOC. The value returned is in milli-Newton-meters.”
(3) Are the ADC voltage inputs needed for the FAST calculations:
EST_getTorque_Nm
EST_getFlux_Wb
Related notes and posting:
(1) References to EST_getFlux_Wb () and EST_getTorque_Nm ()
In the InstaSPIN and Motorware document SPRUHJ1F – January 2013, Revised July 2014:
EST_getFlux_Wb ()
“ gets the flux value in Weber.”
EST_getTorque_Nm ()
“Gets the torque value in per unit (pu), IQ24” and it states that the return value is:
“Return: The torque value, N*m.”
(2) The posting that identifies the units of the EST_getTorque_Nm () function as milli-Newton-meters is:
http://e2e.ti.com/support/microcontrollers/c2000/f/902/p/410275/1458420
“You should use the EST_getTorque_Nm() function call to get torque information from InstaSPIN-FOC. The value returned is in milli-Newton-meters.”
Thanks,
Allan
