STM32F303 - bldc motor control with encoder

[MAhma.6]

Hello, we are using STM32F303 to control a BLDC motor ( 48V, 900 rpm, with encoder) . The motor is working fine most of the time with the generated code using ST motor workbench. However we have the following issues:

1- Motor works fine in torque mode but not in speed mode. It generates so much noise and doesnt spin under load. Without load, spins but the speed is oscillating .

2- In torque mode, when we spin the motor at high speed, it works for a while ( 15 min) and them speed drops as the test goes on ( from 450 rpm to 370 rpm )

3- The other problem is that we cannot run the motor above 450 rpm. applying more Iq does not help. Increasing input voltage does not help either.

I really appreciate your urgent response.

thanks

[MAhma.6]

seems like the ST forum community is so quiet!! Any comments/suggestions?

[Trevor Jones]

I have worked on BLDC for a while now, but I use the Self sensing chips from Ti, DRV10987 (7 on one PCB) 48Watts max

but they are also limited to about that speed...

Isn't there another forum for motor control ?

in my experience you cant use ST code..

you have to hand manicure the timer interrupts and remove or bypass the ST code.

What size motor ?

I wouldn't be task switching like RTOS and I wouldn't be doing any prints or debugging inside interrupts

I have also made a single channel 100A 6000Watt PCB, but Clive has me busy,

so haven't got to code that one yet... based on the F722 and DRV83235

I arranged the Timers to cascade from a primary timer, so adjust one timer for speed and have a PWM list being DMAd on every cycle for power.

[Laurent Ca...]

The question has been moved from the section "Motor Control Hardware" to the "STM32 Motor Control" section (the question is about the STM32 MC SDK). 

Best regards