S12 / MagniV Microcontrollers中的主题 Re: calibration error

calibration error

443115228 — Wed, 27 Nov 2019 10:05:56 GMT

Hi,

I'm using the board MTRCKTSPNZVM128 with 3-phase Sensorless Dual-Shunt PMSM application -FOC driving.

It works normally with the motor NXP provided.

But It can't work when I using my motor .

I changed the parameters as followed:

the fault is coming when the code runs to calibration state,please tell me why?

(state=Calib, Event=e_Calib,and then e_fault comes)

Re: calibration error

pachamatej — Wed, 08 Jan 2020 13:29:32 GMT

Hi,

can you please confirm that the application is going directly from the calib state and not even from a single call of align state?

If the app goes to the align state just for a few steps (thus for few 100 us periods only), the alignVoltage set too high can cause the current to go over the limit. If so, go to the Parameters tab of the MCAT and reduce the AlignVoltage value to zero. If the error occurs again, then we would start to find the problem.

You can step-by-step adjust the voltage to get the rotor in position and at the same time get some reasonable current.

Best regards,

Matej

Re: calibration error

abderrahimjamao — Thu, 11 Jun 2020 09:16:10 GMT

Hello,

I have the same error and when I reduce the AlignVoltage value to zero, the motor goes to the Align state then to the operating state, but the motor does not run.

Re: calibration error

pachamatej — Fri, 12 Jun 2020 06:46:32 GMT

Hello,

Have you tried to request speed form the "green" range? The open-loop start-up might have a problem with such small speed.

Thanks,

Matej

Re: calibration error

abderrahimjamao — Sat, 13 Jun 2020 18:13:58 GMT

Thanks for the advice but the nominal speed of my brushless motor is 280 rpm (it's a Brushless Gear Hub motor for e-bike). Is it acceptable to request a speed higher than its nominal speed?
Best regards,

Re: calibration error

pachamatej — Fri, 19 Jun 2020 13:40:46 GMT

Hello,

if your motor is designed to a different speed range, then I would recommend to adopt the software to it. I believe some background can be found in this document: BLDC six-step control speed scaling using S12ZVM

For electric bike, I would recommend to use different to use torque (current) control structure instead of speed control - just like the throttle pedal in cars is used to command the torque instead of speed.

Even for cruise control, PI controller is not suitable due to the "integrator" included, which can cause overshoots in control and some other difficulties. But I'm not sure any kind of cruise control is useful for electric bikes.

Best regards,

Matej