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Suddenly broken

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moto_guy
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Suddenly broken

 

Hi ,

You can see and hear that  it suddenly cutoff ,so bad....

 

Well, at the beginning everything is good in FOC mode, when PPM duty up to 50% above ,VESC suddenly broken, 

right now the VESC6 is totally dead.

 

moto_guy

 

***********************************************************

 Finally I got it work!

 

sam.vanratt
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Hi moto_guy

which VESC imcarnation are you are using exactly? The VESC6 plus allows 100A continues, the older or thirdparty maybe more/less. From what I've seen I'd say the driver/bridge broke down (=burned out). What I limit did you set?

Cheers

Sam

I'd move the thread to the hardware forum when it's an original one, else contact (so trampa

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

moto_guy
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Hi Sam,

Following the VESC6 schematic I built my vesc board , HW 60, Firmware V 3.4

so far the driver/bridge is not broke down ,it still work in low speed(rpm<4000),low current(motor current < 7A).

when I changed Volt from 25V to 15V , the duty cycle could up to 80% ,but when the rpm close to 4000( ERPM is 4000*7 = 28000) ,it suddenly cutoff anyway and it's too dangerous because the prop will be threw away sometimes.

Almost let me get heat attack during the test. surprise

it seems like it suddenly lost tracking rotor and wrong control the motor.indecision

 

-moto_guy

ESCam
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I'm experiencing a similar issue with my custom board, which is the same components and schematic as the VESC6, but circular like yours (one board not two). I noticed you used SMT caps rather than electrolytic ones. How did you determine what type and quantity you needed? Do you have an official VESC6 you could run with the same profile to compare? 

My official VESC6 can make it to full throttle with this motor, but my board has this issue around 90A motor current. My best guess is motor saturation like in this post, but my my motor current limiting doesn't seem to work and none of the other suggestions. https://vesc-project.com/node/356 "VESC on multirotors - motor high resistance." Could also be an issue with noise on the current sensing or other signals. 

I also have these issues with my VESC6 and custom board. https://www.vesc-project.com/node/841 VESC6 Issues. Battery current inaccurate, positive ramp time, motor current max.

This is testing with a  Hacker Q80 13XS motor, 14 pole pairs. https://www.hacker-motor-shop.com/Brushless-Motors/Hacker-Outrunner/Hacker-Q80/Q80-13XS-F3A.htm?shop=hacker_e&SessionId=&a=article&ProdNr=38798013&p=2986

hacker-motor-shutoff.png

moto_guy
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Hi camdchapman,

 I tried to add 3 big electrolytic caps( 470uF/63V) on my board ,but It no impact on the result. 

Camdchapman,do you fix the issue now ?

I got official VESC6, it can make it to full throttle with this motor, but my board has this issue  right now . so apparently It's not software issue, It should be a hardware problem.

 Do we miss some components in design ? or the VESC6 schematic is just a incomplete reference design for us ? 😣

 

 

ma-j-sterelektron
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Hi, 

Maybe there is something wrong with your pcb design. What about power traces thickness? Can you post your power stage design?

ESCam
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I haven't solved this issue. 

You should rotate your test setup so that if a prop blade did fly off to the side, it couldn't head towards you at the computer. 

I don't think I'm missing any components. I'm guessing that some of the routing that is different than the VESC6 is causing some traces on my board to pick up noise at higher currents where the VESC6 routing doesn't. Maybe that the CSAs are on the other side so the routing to the processor is longer. It could be something else. 

Here is a pdf of my power stage and screenshots. The board is 2.6" diameter.  It should be the same schematically as the VESC6, other than the soft start circuit. The soft start circuit slows down the bulk capacitors charging when initially connecting the battery, but the FET should stay on and have little affect after that. My power trace widths (polygons) are pretty beefy. CSA traces are 15mils differential routed, center tap traces to the DRV8301 are 25mil.

power stage.pdf

esc-power stage.png3esc-power stage.png4esc-power stage.png5esc-power stage.png6esc-power stage.png7esc-power stage.png

ESCam
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Another symptom I should mention is that the ERPM measured will sometimes incorreclty read 200k ERPM after this issue, or sometimes after having a startup issue where the motor squeeks like a parakeet. Here are screenshots of when this happened after a failed startup. startup issue.pngstartup issue2.png

moto_guy
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Put the voltage down to 20V . it work .

 

it still can not work above 24V.

so I have to change 6S(25V) into 4S (14.8V) to work.

 

 

TVAVAE
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We have the samen issue here I think, with our custom hardware... Someone solved their issue?

David_1
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where is the schematic ?