Part Number:TMS320F28069
Hello C2000 Forum,
I have a Portescap, 2 pole, BLDC Motor - Model Number B0610P1005.
Some of the relevant parameters, as listed in the data sheet are:
Nominal Voltage [V] 24
No Load Speed [rpm] 40000
Max Continuous Torque [mNm] 8.3
Speed Constant [rpm/V] 1656
Rs (phase to phase) [ohm] 2.3
Ls (phase to phase) [uH] 500
I'm currently using the DRV8301-HC-EVM evaluation kit.
This is a relatively low inductance motor, so I've been trying to characterize it using lab02c.
It starts off just humming, while lab02c is evaluating Rs. Then it stops. Then it runs pretty
smoothly for a little while. During this period I can see the Flux value getting updated.
Finally, it goes through an interval where it's running extremely rough. I can see Ls_d
and Ls_q getting updated during this phase.
The numbers I'm getting for Rs are relatively close to what I'd expect (1.2), but the Ls
values are 1.5X to 2X the values I’d expect (I’d expect around 250uH, about ½ the phase
to phase specs from the datasheet). Flux usually shows up as around 0.021 V/Hz.
The motor also runs very rough and heats up quickly in the subsequent labs (e.g. lab03a).
I’ve varied the following parameters, as shown below, but the results don’t get any better:
USER_PWM_FREQ_kHz: 20 – 60, in steps of 20
USER_NUM_PWM_TICKS_PER_ISR_TICK: 1, 2, 3
USER_ZEROSPEEDLIMIT: 0.25 to 1.0 in the numerator, steps of 0.25
USER_FORCE_ANGLE_FREQ_Hz: 0.25 to 2.0 multiplier, steps of 0.25
USER_MOTOR_RES_EST_CURRENT: 1 – 3, in steps of 0.5
USER_MOTOR_IND_EST_CURRENT: Always -0.5*USER_MOTOR_RES_EST_CURRENT
USER_MOTOR_MAX_CURRENT: 10 – 20, in steps of 5
USER_MAX_ACCEL_Hzps: 10 or 20
USER_ADC_FULL_SCALE_CURRENT_A: 60 or 82.5 (default)
USER_ADC_FULL_SCALE_VOLTAGE_V: 45 or 66.32 (default)
I tried a bunch of permutations of combinations of the above settings. I tried to limit it to ones that seemed practical,
or seemed to make difference, or seemed to have an effect in conjunction. I have a spreadsheet with
these permutations and their effects, if you want to see it. I also have the data sheet for the motor.
I’m obviously missing something…
Maybe I've got some crazy parameter values somewhere. I've attached the user.h file.
Could you please help?
Best Regards,
Dave Reagan