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5phase Vesc based on 75/300

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BartE
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5phase Vesc based on 75/300

Me and my son are building a e-scooter with a 5 phase BLDC motors we have handy (25 poles). The idea is to build the driver based on the Vesc 75/300. 

Can anybody predict how difficult it would be to change the Vesc firmware for 5 phases. 

How compatible will that be with the Vesc tool?

All advises are very much appreciated. 

PS : Some people likes to join building this thing. That makes the efforts smaller...

vadicus
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Just wondering why 5 phases, not 7 or 11?

 

 

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pf26
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Why do you assume only to change "Vesc firmware" ?  It seems you first need change VESC hardware (to drive 5 phases instead 3). That means massive rework - not even sure that the chip in use has enough fast timers/PWM output to do it. Or maybe I am missing something..

BartE
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Of course the hardware needs to be reworked. I did not mention this as I have a better idea what it takes to do that. And yes... I do underestimating mostly the time i spend to finish projects frown.

I hope to be inspired by the original design of the Vesc 75/300 to make the power routing well...

100 pin MCU from the same family offers 16 timers for PWM. Is I can understand from the schematics there are just 2 PWM's per phase needed. 

I did not looked into the firmware source code what it should take to expand it to 5 phases. I hope to get a better idea how easy are difficult it is to fit this into the firmware from the people on this forum.

BartE
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Vadicus : Might be an idea to make the number of phases modular. 

vadicus
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Seems like rewinding into three phase would make way more sense. 

 

 

NextGen FOC High voltage 144v/32s, 30kw (https://vesc-project.com/node/1477)

BartE
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How do you divide 25 poles in 3?

Pimousse
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Could be wrong but you might need a beefier MCU with 5 ADC.

That will ask some rework on this side as well. Not an easy task I guess.

vadicus
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There is a chance you can run this motor using 3 out 5 phases with some code adjustments. If this is a purely educational project, introducing unnecessary complexity would make sense. However, if the goal is to make a viable product and time/money is not without a limit, it would be worthwhile to reconsider the motor selection. There is a reason 3 phase approach is pretty much standard in motor drives. There are some very specific use cases for more phases but a scooter is not one of them. 

 

 

NextGen FOC High voltage 144v/32s, 30kw (https://vesc-project.com/node/1477)