Recent content by peters

I made a fix for my BMS connector oxidation problem mentioned above (May 07 2021) without replacing the connectors, but with a firmware modification that I thought to present briefly. Now when a cell voltage is at the top, the shunt (or bleed) resistor is switched with a 50% PWM signal, and the...

Inside the frame since 2013-14, already a bit obsolete:

FS bike status after 7 years of moderate use (1500..2000km/year). Still using the original 1400Wh headway lifepo4 batteries that I usually discharge to 30-40%, but I wanted to check its condition so I went to fully discharge it. I took a trip to an abandoned air defence missile base from the...

I though of training the NN for the actual motor like calibration, save the config in the flash, and use it afterwards normally as a trained NN.

Yes, saturation can be a problem. I just want to do wheelies and climb any hill, that should work without the halls. Another option is a neural network-based observer. It may seem to be overkill at first, but since the phase inductance is a nonlinear function of only a few variables and every...

Not much progress yet, the project is paused for a while. I've set up the ADC to measure the phase currents and Vbat twice in a pwm cycle (center-aligned pwms): the sample taken in the middle is used for the FOC loop, and the sample at the start will be used for inductance measurement with HFI...

It's called "copper inlay", I'm also wondering how it would perform compared to a bunch of vias.

It's exactly intended for that (~6.8V on this diode), because Vbat rises at regen and I want the battery voltage as close as possible to 100V with some headroom at the converter input. There are no spikes on this node (unless intentional with an EM surge generator :)), but I agree I could have...

I can only guess, the loop is smaller, but is there space between the FETs for shielding or overlapping layers? I don't know which is better: a small loop without shielding or a slightly bigger loop with shielding. Yes it's useful. Maybe I'll try but now my circuit is assembled and mounted to...

It just reduces the input voltage instead of a resistor, but not a solution to the stability problems with LM516x. I had the same, but works well with the type2 feedback circuit and the frequency set to be always in continuous mode. Type3 is probably better for output regulation without serial...

Maybe a short twisted pair or shielded wire soldered or contacted to the pins with the smallest loop. Try a wire loop similar to the one I used to pick up di/dt, but smaller, with that you could find the probe orientations where there is no induced voltage. Resistor divider would just reduce the...

Thanks, very informative waveforms, good to know that such low inductance is feasible. But I think I would try to switch this circuit faster to reduce the switching losses, at least the turn-off, even if that would induce higher overshoot. But it's my personal preference. The Vgs and Vds rise...

No, I didn't think it's a 700A test. :) If I can guess it's with SMD FETs at relatively low current intended specifically to test the Miller turn-on. Inductance is low because there are no signs of inductive voltages, but there is some current because of the fast 30V jump at the Vds rising edge...

Marcos can you tell a few things about the circuit that produced the waveform you attached above, if these are not secrets? FETs, Rg_on, Rg_off, if external Cgs is used, current sensor is under the low side FET or on the phase output, and the current at this test?

I think it's very good as it is, at 100A the current turn off time would be less than 20ns with smaller overshoot. RC snubber wouldn't reduce the overshoot, that is only useful to stop the HF oscillation. For the miller turn-on it's hard to tell exactly what is going on on the internal Vgs...