KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)

[endlessolli]

@stancecoke @Xnyle it brings tears to my eyes to see the both of you back here! The og creaters of this amazing firmware + Bluetooth app!

I would like to convince you that this firmware is not dead and that it provides unique value to the ebike community that other controllers simply cannot offer. People keep coming back to try and further optimize the firmware. The combination of a small form factor of the controller, high power (15 kW+ from the 18 fets), low weight (1 kg), flexible firmware that is reasonably easy to read and edit, native PAS support, (simplified) FOC, flexibility in screen options (lcd3, 8, app or none) + still active community is simply unmatched by any other controller I have encountered so far.

There a still things to be polished and added in (preferably) a user interface (as far as I am up to date/aware):
- display motor temp in kt-lcd 3, with the same logic (10k thermistor) as in the bluosec app. An active customizable upper limit would be highly needed to protect our motors from the large phase currents that the 18 fets can produce.
- easily accessible and customizable field weakening that obeys a certain max in phase amps.
- easily accessible and customizable ramp up time to set duty cycle. I always change this manually in the firmware from 2s to 0.5s. This greatly increases responsiveness/aggressiveness of the throttle response and enables things like instant wheelies.
- optimization of the zero amp finding routine: i have recently started editing this, with double the wait states and 1/10 the zero amp threshold (from 2amp to 0.2amp i believe). This has greatly reduced the power loss at idle, now showing some 50watts at idle on the screen instead of the original 250watts (real losses from 3w to 0.3W or so; much less hot to the touch). Maybe this influences drag when coasting; i did not test that yet.
- implementing the motor constant as a settable value in the java script.
- checking the stability of recent updates to e.g. regen braking (i tried Andrea’s updates and instantly fried 2 controllers so i went back to the original stancecoke, xnyle and torque from x4 master branch, that has always worked flawlessly with powerful regen braking up to skidding the rear wheel). This checking is up to us as a community of course.
- cleaning up all tested modifications in a new master branch + optimally an updated java tool + bluosec (but that is wishful thinking )

Of course, we can keep editing the firmware directly by hand, but that would probably lead to chaos in the long run. So a skilled owner would be highly appreciated as this firmware is really a piece of art! And so are the controllers, simple and crappy as some may call them.

See some pictures below as a tribute to the work that you did on the firmware: a 35kg 15kW carbon mtb that has been running your amazing firmware on a modified 18fet kt controller (200batt amps, 300phase amps, oil filled and actively cooled) very reliably for years now. This performance in such a small form factor and for such a low price is still unmatched by all modern controllers in my opinion.

So let’s keep the kt firmware development alive!

I agree 100% to all the above!
One question to this @Iambuilderman :
"

ramp up time to set duty cycle. I always change this manually in the firmware from 2s to 0.5s. This greatly increases responsiveness/aggressiveness of the throttle response and enables things like instant wheelies.

"

Could you point me to where what needs to be edited?
I could also use a faster response to the throttle in my use case.