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Noised signal from motor NTC sensor | HW4.12 FW3.27

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ma-j-sterelektron
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Noised signal from motor NTC sensor | HW4.12 FW3.27

I just upgraded to new fw from 2.18. My HW version is 4.12.
There is my build: https://endless-sphere.com/forums/viewtopic.php?f=35&t=86275

With old HW I don't experienced any problems running FOC. But with new fw it cogs slighly(more like vibrates), most noticeable it is when I am accelerating uphill from standstill. And a had  few cutouts after going uphill a then downhill. Motor detection was made without belt. I think there is possibility that it is caused by noised signal from motor temp sensor.

https://i.imgur.com/yTZMxdq.png

Noised signal
Caption

So I can try to connect capacitor for filtering, or use shielded cable. Is there the way to turn off motor temperature limit?

Or maybe Benjamin should implement some sw filter.

EDIT: I can see picture in edit but not in post.
Added link.

benjamin
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There already is filtering in hw and sw, so the noise should not be that bad. One thing you can try is disconnecting the temp sense cable and see if it helps.

also: I think images should work now

ma-j-sterelektron
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So I disconnected temp sense cable and it didn't help. I tried to run different erpms from VESC tool to see how it behaves.

It's worse in sensored than sensorless. Here are screenshots:

Sensorless:

And sensored:

 

 

Detail:

 

 

ma-j-sterelektron
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I decreased speed tracker Ki from 40000 to 20000 as was in old fw and it's much better now. Will report later after test ride, as I have to work now.

ThierryGTLTS
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How did you implement the hardware to measure motor temp?!

In my view, on the 4.12 board, we need to remove the 10K resistor R7 and put it in parallel with (solder it above) C4.

Then we can add the 10k thermistor of the motor (I will glue one on a stator winding) and connect it between Vcc and Temp In.

The one I have has a slightly different beta, so I will enter the value in the box of the new VESC Tool (FW3.28), and normally all is done.

Am I right ?!

Have a Nice Day.

Thierry

ma-j-sterelektron
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I have sensored motor, so there is already NTC thermistor inside. Of course you can add it yourself, you just have to connect it between +5V and TEMP on the connector for motor sensors. No need for modifications.

On topic: Decreasing speed tracker Ki helped, acceleration from standstill is now super smooth, even uphill.

ThierryGTLTS
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Thanks.

I've decreased speed tracker too, and yes it's better now.

Will have a try soon.

Have a Nice Day.

Thierry

ma-j-sterelektron
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Thermistor inside the motor is actually between TEMP and GND, sorry. Mosfet thermistor is between VCC and GND.

ThierryGTLTS
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Right, it's clear now.

Have a Nice Day.

Thierry

ThierryGTLTS
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Hi ma-j-sterelektron,

How do you have such a clean graph with large temperature scale?

Mine are always resizing to such a small range that I can't read anything.

Is there a way to choose or to block scales, also for current and rpm?!

Have a Nice Day.

Thierry