Hello, I'm running a BLDC motor in no-load condition using the firmware from the S32K BLDC/PMSM Development Kit, specifically the PMSM FOC 2Sh firmware. While operating the motor, I noticed that the graphs for certain RPMs (e.g., 2000, 3000, 4000) differ from those at other RPMs (such as 2500 and 3500), which generally follow a more consistent pattern. When measuring with a tachometer, the actual RPM usually matches the target RPM, but for those specific RPMs, the motor fails to maintain the required speed accurately - although the error is not very large. (like ±10 RPM) Could you explain why this problem occurs?
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Seems a motor parameter tuning issue…
Depending of the S32K BLDC/PMSM Development Kit, it use by default the Sunrise motor 42BLY3A78-24110 or the Linix 45ZWN24-40 motor, and use the following parameter file, for example:
In case you change the motor, the appropriate electrical parameters must be entered and tune the parameters of the different control schemes.
I recommend you to take as reference the following training to learn how to use our MCAT Tool:
Motor Control Application Tuning (MCAT) Tool – PMSM Servo Tuning
I hope this information is helpful.
