BLDC motor torque problem

[Madbunny1]

Hello all,

Can anyone please tell me the ways on How to achieve the high torque at low speed in BLDC motor control? I am going to do it with with Field oriented control sensor less commutation?

Thanks in advance

 

[BradtheRad]

Torque comes from magnetic attractive/repulsive force. The force is maximum when coil and magnet are close.
Therefore I can only picture that you'll need many coils and many magnets, if you want slow speed and high torque.

 

[Madbunny1]

Torque comes from magnetic attractive/repulsive force. The force is maximum when coil and magnet are close.
Therefore I can only picture that you'll need many coils and many magnets, if you want slow speed and high torque.

Thank you for the answer.
I am using 5 pole pairs in the rotor(permanent magnet), Three phase windings(stator coils with star connection)? And is there any other ways to achieve the high torque with low speed?

Thanks.

 

[KlausST]

Hi,

with correct excitation the torque is about linear to current.
But you need to choose the correct phase angle, too.
The torque may be about independent of speed. You should find the max. torque information in the motor datasheet.

***

But all this are basics for BLDC control. There are many ways to achieve BLDC control.
I think a froum isn´t the right place to learn all the basics. A forum can´t replace a school.
My recommednation: Read books. Additionally there will be a lot of tutorials often as youtube videos....
And you need to do a lot of math. You need the correct hardware you need the correct software. You need to decide the regulation loop.

For us, who want to help, there are a lot of questions about your application.

Klaus