You are here

Sensorless BLDC start problem

3 posts / 0 new
Last post
MikeStros
Offline
Last seen: 2 years 4 months ago
Joined: 2018-05-15 14:07
Posts: 1
Sensorless BLDC start problem

Hello everyone.

At first, I want to say thanks to the developers of this awesome ESC. I'm using it at my projects for a long time and it works almost perfect.

 

Now I'm trying to use vESC in my big hoverboat model. The motor is T-motor U8 135kv with 30" solid carbon propeller, it was previously used on large quadcopter and was presented to me without ESC.

My vESC is HW version 4.11 and SW version 3.38, mode is sensorless BLDC​. The problem is bad start with propeller attached to motor (without propeller it start good). ~30% of starts happens in reverse direction with weird commutation noises. With adding throttle speed of wrong rotation and noise increases. I was playing with settings for few hours and was unable to find good combination of parameters for good reliable start. Adding minimum duty cycle to maximum value of 10% raised a chance of good start a little.

I also tried to flash old 2.xx firmware and the newest one, but motor start looks always the same. 

Please, help me to find solution. Maybe I need to recompile FW with some unusual parameters of change some hardware for reliable start of this motor with large propeller?

Thank you!

skyline1970
Offline
Last seen: 1 year 2 weeks ago
VESC Free
Joined: 2017-09-07 22:28
Posts: 232

It seem to be that the motor needs much more currents, and it can not start flawlessly.

You could try with detection current value increasing.

In fact, new vesc tools have simple motor selection wizard. This is also worth to try.

At application settings, current mode also could solve this problem.

 

dekafive
Offline
Last seen: 4 months 4 weeks ago
VESC FreeVESC Original
Joined: 2018-08-17 20:57
Posts: 9

"You could try with detection current value increasing"

This sounds cryptic to me :-(

 

How do i have to do that  in VESC-Tool?

dekafive