Lot's of noise on motor temperature reading cause jerkiness

Hi everyone

As some of you might have seen I’m experimenting a lot these days comparing single to dual drive

One problem I’ve encountered is when using a single motor at higher currents the noise induced by the phase current on the temperature measurement is a lot higher than in a dual motor setup, so when operating near or at the temperature limit a lot of jerkiness occur due to the temperature cutoff being completely irregular, going in and a out a few times each seconds, this causes a similar feeling to the radio cutting out and can be quite dangerous if you are not expecting it

Bellow are two logs of the same hill climb, one with single and other with dual

I posted on the VESC forum a suggestion to implement a filter on the motor temperature reading to avoid that situation, @Trampa I don’t know if Benjamin is following the forum closely but I would appreciate if you could bring the issue to him

Anyone had a similar experience?

Cheers

Single: https://metr.at/r/wUFFn

Dual: https://metr.at/r/5U2GG

am i reading this graph right? it looks like on the single (as well as the dual) the motor temp average is slowly dropping slightly while the altitude increases, meaning its cooling off going up hill? what’s up with that?

My bad, uploaded the same log twice, now it’s correct

Also I’ve seen this happen since the thermistor itself gets a lot of fresh air when the motor starts spinning to the temperature drops

On top of that I had switched single and double, but the main point is the amount of noise on the reading

This logs shows better since I was making it reach the cutoff, at around 16:08 you can see how much noise there is, that’s when the jerkiness starts

ewww yeah there’s a fuckload of tiny spikes there

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I have had that, the trick was to move the phase wires away from the sensor wires and not jam them in top of each other.

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Nice, how far apart you run them? Maybe find a shielded 6 wire cable

the noise from phase leads fucks shit up. Sensors as well as receiver signals. Don’t ever put your remote receiver near the caps or phase leads on the ESC. I usually run mine back and lay them next to the battery, if not all the way forward to the front of the enclosure.

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