Why does my motor not reach setted speed when load is too heavy, and why does SDK 5 not stop motor by speed feedback error?

[afici]

I'm a newbie in motor control. I'm working on STSPIN32F0A for control a 24V BLDC motor.

It was very simple configure e control the motor at different speed (2900 to 3400 rpm) with no load. I've got only some measure(rpm / phase current / torque / power abs. at load, and at no load) about the motor given by manufacturer, but also LS , RS, Ke, Ki. When I try to add load to my motor, speed begin to decrease at values below the setted one. Why motor doesn't stop for speed feedback error? and why at certain power absorption value is the motor speed low than what manufacturer say? thanks

[Amrit Singh]

Are you using the Evaluation board ?

[Claire O.]

Hello,

Can you please explain which Eval board you are using and if you are using a code example from the SDK or if you regenerated the SW?

Thanks a lot,

Claire

[Enrico Poli]

Hello,

did you tried to increase the peak current in the motor parameters? When the speed loop reacts for compensating the load change, the target current is saturated in order to fit the range indicated into the motor characteristics. This automatically limit the maximum motor torque.

Regards

Enrico

[Davide Zanni]

Could be a limit of the system, you reach the max limit of the PWM duty cycle. In this case the circle limitation of Vdq don't permit the duty cicle to brake the board.

Could be usefull see this limitation in the Motor control workbench.

[Laurent Ca...]

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

Best regards