No PWM output  [SOLVED]

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lumax
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No PWM output  [SOLVED]

Post by lumax »

Hi everyone!

I'm experiencing problem with my hardware testing... I got no PWM output on any of the 6 output
Current and voltage sensor have been configured correctly, all CAN message are disable, il1 and il2 read +/- 0A on manual run...
When I push (start manual mode) the PWM output get pulled to GND (0V) and when i push (stop inverter) i got around 200mV
IN_MPROT is pulled high (12V)
IN_FWD is pulled high (12V)
RESERVED is pulled high (12V)
START is left floating
DESAT is left floating
Resolver not connected or connected is the same (except the LORESAMP warning)
Gate driver are not connected
DC bus = 80V (limited to 10A)
Current sensor at 0A = 1.67V


I got the following error in manual run (opmode2)

[66525]: WARN - LORESAMP
[67705]: WARN - HICUROFS1
[67705]: WARN - HICUROFS2
[66524]: WARN - LORESAMP

Here is my parameter for the latest sine firmware

Code: Select all

"boost": 1700,
"fweak": 90,
"fconst": 180,
"udcnom": 0,
"fslipmin": 1,
"fslipmax": 3,
"fslipconstmax": 5,
"polepairs": 2,
"fmin": 0.5,
"fmax": 550,
"dirchrpm": 100,
"dirmode": 1,
"snsm": 14,
"pwmfrq": 1,
"ocurlim": 100,
"minpulse": 1000,
"il1gain": 1.5,
"il2gain": 1.5,
"udcgain": 2.12,
"udcofs": 132.9,
"udclim": 540,
"bmslimhigh": 50,
"bmslimlow": -1,
"udcmin": 0,
"udcmax": 520,
"iacmax": 5000,
"idcmax": 200,
"idcmin": -50,
"tmphsmax": 100,
"tmpmmax": 300,
"throtmax": 100,
"throtmin": -100,
"ifltrise": 10,
"ifltfall": 3,
"chargeki": 80,
"potmin": 10,
"potmax": 4095,
"pot2min": 4095,
"pot2max": 4095,
"potmode": 0,
"throtramp": 1,
"throtramprpm": 20000,
"ampmin": 10,
"slipstart": 50,
"brknompedal": -20,
"regenramp": 1,
"brknom": 20,
"brkmax": -15,
"brkcruise": -30,
"brkrampstr": 15,
"brkhistr": 1000,
"brkhistp": 1000,
"brkout": -50,
"idlespeed": 500,
"idlethrotlim": 60,
"idlemode": 3,
"speedkp": 0.18,
"speedflt": 5,
"cruisemode": 0,
"udcsw": 0,
"tripmode": 0,
"pwmfunc": 0,
"pwmgain": 100,
"pwmofs": 0,
"canspeed": 1,
"canperiod": 0,
"fslipspnt": 1,
"ampnom": 10
Sorry if some sentences make non sense... I'm French!
Bart
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Re: No PWM output

Post by Bart »

Hey Lumax,

I am also quite new to this, but I had a similar problem a while ago. Could you try and see what happens to 'opmode' when you start in manual mode? You could for example type 'start 2', and then 'get opmode'.
At the end, it turned out I was too enthusiastic and connected 'IN_START' to 12V, this caused the inverter not to run in manual mode, but in 'normal' (opmode=1) instead, this is why I asked the question above.
I also think that the current sensors are only measured in opmode >0, and if you just see a flat line for il1,2, it means that it is actually not reading out the sensor. On the other hand, if you see some fluctuations around zero, I think the sensor readout is OK.

I hope this helps,
Bart
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lumax
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Re: No PWM output

Post by lumax »

Hi Bart!

Thanks for your reply,
Start input is floating and I use the start manual mode button in the web interface, Il1 and Il2 are correctly reading in opmode 2 (I got 1.66 and 1.67V @ 0A) they accurately read +100 and -100A

Today I spend to many hours to try to troubleshoot this issue, I guess I will have to probe the logic gate hardware shutdown to see which input is low... But I'm pretty sure this is related to the HICUROFS

Thanks for your time!
Sorry if some sentences make non sense... I'm French!
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lumax
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Re: No PWM output

Post by lumax »

I tested it again this morning and suddenly I got PWM on all output... but the trace was ugly... almost a triangle wave (like too much capacitance) and the gate driver was still not connected ????

A couple minutes later I stop it to adjust the dead time and no more output... flat line at 0V ???

I will replace current sensor with potentiometer to see what is going on
Sorry if some sentences make non sense... I'm French!
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lumax
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Re: No PWM output

Post by lumax »

I have found the problem for HICUROFS1 and HICUROFS2 the version 3 board got a voltage divider builtin for 5V current sensor, so at 0A the current sensor output voltage should be between 2.2V and 3.4V (ideally 2.5V) if the voltage is out of this range you will receive HICUROFS error

The V3 board wiki say
"Il1 (Pin 6) Current phase 1. 0V=-Imax, 1.67V=0A, 3.3V=Imax (software configurable). Cutoff frequency 48kHz."

The error code wiki say
"14 HICUROFS1/2 DISPLAY Current channel 1 or 2, respectively, is below 1.23 or above 2.06V when no current is flowing. Check wiring and voltage dividers"

Please update these 2 information

I got no more error except PWMSTUCK and still no PWM output
Sorry if some sentences make non sense... I'm French!
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johu
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Re: No PWM output

Post by johu »

You can ignore PWMSTUCK. It might point to a problem but it's not the cause. Have you configured Acthigh for pwmpol? Do you see dir != neutral?

Sorry for the glitch in docs will fix out later
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lumax
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Re: No PWM output

Post by lumax »

Hi Johannes,

I did not play with the acthigh and direction is in forward...

This is weird, I have found that when the board is disconnected for "let say 1 hour" when I get back to testing and power up the board I got around +2.5V steady in all of the PWM output (no gate driver connected) when I start in manual mode I got a pwm signal at the correct frequency, but amplitude is quite small less than 1Volt and the amplitude decrease with time after 1 or 2 minutes amplitude is less 10mv... In this time the pulses are all distorted on the rising edge (look like a capacitive load)

After this time when the inverter is stopped the voltage on the PWM output is around +200mV and when I start the inverter this voltage drop to a steady 0V
Sorry if some sentences make non sense... I'm French!
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Re: No PWM output

Post by johu »

I assume nothing is connected to the gate drive outputs. It sounds like totally blown output drivers.
They are tested here, but of course not long term. I just toggle the outputs and read them back via looped back input pins. That said the test expects state change to be almost immediate, so defective output drivers would probably be detected. Do you have the possibility to swap the stm32?
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lumax
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Re: No PWM output

Post by lumax »

I could try, I did this 2 or 3 time with quite similar package ... But do I need special hardware to flash the boot loader in this MCU, never played with STM ?
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Re: No PWM output

Post by Isaac96 »

You need an ST-Link device.
https://www.ebay.ca/itm/ST-Link-V2-Prog ... Sw53hbzWjz

I believe some fake ones fly around from time to time, but the STM32 Nucleo boards include an STLink on the board which you can use (that's what i've got).
https://www.mouser.com/ProductDetail/ST ... bL2w%3D%3D
-Isaac
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Re: No PWM output

Post by johu »

If it wasn't for the overseas delivery troubles I would just send you a new board.
Also look here: viewtopic.php?f=2&t=6&p=16
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lumax
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Re: No PWM output

Post by lumax »

Ok, I will give it a try... If it doesn't work as expected I will pay for shipping and trouble to get an other board

Thanks!
Sorry if some sentences make non sense... I'm French!
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lumax
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Re: No PWM output

Post by lumax »

Just to let you know... I have finally found some time to test the new brain, and now I got PWM signal!!!

Yeah!!!
Sorry if some sentences make non sense... I'm French!
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