Scientific analysis of BBSHD! Motor characteristics, Winding pattern, ...

[Tomblarom]

I just stumbled across this highly scientific paper about the Bafang BBSHD. It features a lot of need greedy details about the characteristics of the motor itself. I can't exactly interpret them, but wanted to share them here.

https://www.researchgate.net/publication/339978831_Design_Validation_and_Performance_Evaluation_of_a_BLDC_of_Commercial_Electric_Bike_and_Its_Performance_Comparision_with_Different_Probable_Designs

 

[afzal]

I just stumbled across this highly scientific paper about the Bafang BBSHD. It features a lot of need greedy details about the characteristics of the motor itself. I can't exactly interpret them, but wanted to share them here.

Nowhere in the paper BBSHD was mentioned, seems it was figured out from the pics

 

[Tomblarom]

Nowhere in the paper BBSHD was mentioned, seems it was figured out from the pics

Yes I looked for "winding layout" and this picture showed up on Google. Found it by accident. I think this is a very nice find, if you want to work with BBSHDs and develop controllers for it. Paper is from 2019, I wonder why nobody found it earlier..

 

[sysrq]

Looks like the BEMF showed in the BBSHD paper is more similar to the trapezoidal example provided by Texas Instruments.

Hard to believe this might mean that staying with the stock controller might result in best efficiency and torque production compared to any low Rdson mosfet FOC controller?

https://www.researchgate.net/publication/279533812_Efficiency_Comparison_of_Trapezoidal_and_Sinusoidal_Method_for_Brushless_DC_Motor_Drive

[FAQ] Trapezoidal Motors vs. Sinusoidal Motors - Motor drivers forum - Motor drivers - TI E2E support forums

Brushless DC motors fall into one of two categories. either Trapezoidal or Sinusoidal. This distinction refers to the Back Electromotive Force (Back-EMF) of the

e2e.ti.com

 

[afzal]

Looks like the BEMF showed in the BBSHD paper is more similar to the trapezoidal example provided by Texas Instruments.

Hard to believe this might mean that staying with the stock controller might result in best efficiency and torque production compared to any low Rdson mosfet FOC controller?

VESC has BLDC mode (in addition to FOC mode), which is suited for trapezoidal bemf motors. IIUC, that mode doesn't get much emphasis & testing currently, so unsure how good ATM it is.

Luna Cycle have VESC on BBSHD, someone with the setup would need to change to the mode from FOC to BLDC (assuming it already is in FOC mode) & see how it performs.

 

[sysrq]

VESC has BLDC mode (in addition to FOC mode), which is suited for trapezoidal bemf motors. IIUC, that mode doesn't get much emphasis & testing currently, so unsure how good ATM it is.

Luna Cycle have VESC on BBSHD, someone with the setup would need to change to the mode from FOC to BLDC (assuming it already is in FOC mode) & see how it performs.

Someone probably has done it already by now since this is considered to be such an old motor.