Learning Forum

[Farshad]

Hello.
I have designed a BLDC motor (PCB motor) in 2D space and excited it with chopped current control excitation circuit. When the motor works at its nominal operating point, negative force is obtained, which is not desirable. Is there a solution to achieve positive force?

Thanks.

[GLUO]

Hi,

Since you are using a constant speed, please make sure the initial position and the current phase is aligned to provide a positive torque. Please also check the if magnet magnetization direction is correct. 

GL

[Farshad]

 

 

 

Hello. First of all, thank you for your quick response. In the following, I would like to tell you some things that may better understand my problem. I proceeded exactly as per the software example for the constant speed settings. In the software, there is a typical example for a DC brushless motor, which happens to have 4 poles. So I expect to get the same results as when I ran the example. The difference between my model and the example is only an additional rotor and the motor being axial flux. The direction of the magnets is correct according to the electromagnetic field. In the mechanical transient mode, the motor works properly and the results are favorable. This problem appears only in constant speed mode. Is there a way to solve the problem?

With respect and many thanks to you

 

 

 

[Farshad]

Hello. I wanted to sincerely thank you for your great help. You were right and I had a problem with the bounds where Bm= -Bs.