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VESC 4.12 with big-BLDC problem

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sam.vanratt
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VESC 4.12 with big-BLDC problem

Hi all

I tried to get further with my bike motor and the VESC I'm planning to use.

The motor (MagicPie3) is a 63Slots:54poles +latching HALLs and is quite a heavy weight with 9kg Hub only (12kg complete). The VESC is a standard 4.12; Testing PSU is a EA-PSI 9080-120 (80V/120A max.).

The autodetect of HALL works without interfering, Motor in FOC is as I'd say OK (eRPM down to 150 because of the weight I guess), blockcommutation is reporting an error about failing when tried.

When I apply throttle voltage to adc1 it stutters from start and extreme under full load. I started with 20A and 28V; tests were tried as well with 10A and 5A.

 

Where can I start to get it working/debugging. The motor runs on some other bike with a Kelly Sinusoidial controller, not mentioning any problems, so I guess BC and FOC should work (BC is the int. default controller).

Cheers

Sam

 

 

 

 

sam.vanratt
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Last seen: 10 months 2 weeks ago
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Hello all

I could not make the MP3 work fluently in FOC up to now. In BlockComm mode I get (no matter what parameter am I varying) the autodetect not working at all so I stopped messing around in Block mode

Does anyone here have heavy motors running with the VESC? Up to now I read only about big motors (70V, 100A+), but most seems to have modell motors running. Am I wrong?

If I could not solve it the next week I've to step back to some Kelly controller or the original GoldenMotor one and dump the VESC controllers as there are no feasible way (for me) to get it running on my bike.

Cheers

Sam

 

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

sam.vanratt
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P.S.: Is there a "professional" (=pay per help) service available yet or heard about one?

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

e-nduro
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If I understood correctly, you have problems with the FOC identification process. I have similar problems when testing big motors in my dyno. I normally try to help the motor to run when it tries to move (not before), and eventually I got the identification success, but it may take several attempts.

sam.vanratt
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Hi e-nduro,
thanks for your reply!
No, the FOC ident works flawlessly and very similar to what Benjamin showed for FOC in his youtube video. My BLDC (=Blockcommutation) detection is not working at all, but FOC works, but when I use this autodetect values after saving the motor stutters especially in light mode as well under full mode; later is more or less moving to and fro. As the HALL detection works as intended as well I'd only guess that start (Sensored up to 2500erpm) got some strange parameter which screws up the smooth polyphase mode. While I earn my living with designing Li charger electronics I'm at a loss when it comes to motor regulation parameter. The VESC looks really incredible featurerich and I'd like to get it working for the thought of opensource.
Cheers
Sam

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

sam.vanratt
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Today I checked voltages just to understand what might be wrong in the setup. As the motor looks good AND works in the "diagnose" area when I apply the duty cycle (,20-0,50 tested) just as it should. Current works as well, just the RPM function does not produce a movement but rattles. With the cursor keys the motor does nothing but consuming power, so I didn't fiddle around with them, as I do not know what they should do.

I'm using the "Current noReverse Brake ADC2" setting, which I understand to apply a voltage at ADC1 (in my case a HALL throttle with 0,9V-3.3V output) and have the ADC2 with my brakes connected (low active)

When I'm in the Input Wizard and chose the "Current noReverse Brake ADC2" setting for ADC the ADC1 jumps to 1,34V with no input connected. With a 22k PullDown resistor the voltage sinks to 1,22V. This does sound wrong at start. As I have two identical VESCs I tested the second one with the same app settings and it behaves the same. In addition the ADC1+2 is directly connected to the STM32 so no possible wrongdoing (PCB) here. When I connect the throttle the startup/running problems occur but the motor does not start until it reaches 2,3V.

What am I doing wrong? I will open another thread for maybe incompatible Firmware (3.40) to my Hardware (4.10) as I could not explain the biased voltage (1,34V) at startup with fitting setup values from the right firmware.

Cheers

Sam

 

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC

sam.vanratt
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Last seen: 10 months 2 weeks ago
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Hi all

yesterday I had time to dive into my bike project again. Thanks to a colleague I used an external ST32 debugger to look into the uC what he's doing. After a few minutes of fiddling around it was pretty clear: the stuttering comes from braking all the time (accelerating-braking, accel, braking, a few times a second) AND the 5V pin on my first VESC has been badly soldered and connected with mOhms to a few kOhms depending on "mood". As I had no brakes attached at that time I figured out that

a) no matter what profile I used (PID, Current, ...) the ADC2 was always looked into and used as brake

b) the brake input is used as analogue input

c) no pullup/down resistors attached or in the uC defined at the ADC1 or 2

d) very high noise/influence from the board itself (that's why I had 1,34V open connect voltage which fluttered between 1V and 3V

 

So my first problem with the stuttering was solved (10k pull up Resistor to 3,3V and ADC2 inverted as my digital brake pulls to Ground), just as well as the smooth running.

What's open is the startproblem (short start, (overcurrent?) and then stop from instant startup with no slow start, but for that I'll open another thread.

 

Cheers

Sam

Pedelec usage in combination with a GoldenMotor MagicPie3 BLDC