Lol it’s not my first choice of esc either but 12s at 80a can pack a punch. It’s pretty impressive that a tenka can run sHFI modes well enough to enjoy it.
I’m ~155lbs so my 3kw short board now packs enough of a punch to pull the front end up without using the tail.
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I thought it only had the double shunt like the Unity?
It is a two shunt design. sHFI seems to run on a wide variety of hardware with mixed results, although it’s not quiet unless you have phase shunts.
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Silent HFI 45 deg v0v7 working very well with a stormcore 60d+ and tb6380s. It is not silent, but it is much quieter than normal HFI. The video doesn’t portray this well but the HFI whine is much better for sHFI than normal HFI, which is quite loud.
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Just wanted to clarify this a little. For silent HFI to be truly silent for upper hearing range you want to set the frequency of PWM to at least around 30kHz. This is right on the edge of processing power of the STM with all the other lifting it is doing on dual hardware so that part makes single better for silent HFI. Not sure where the exact limit is there as I haven’t tested in awhile.
But if you put phase shunts on a dual hardware single mcu setup it would still operate just as silently as a single motor esc at the matching PWM frequency. It’s just a question of if the max frequency you can use on a dual is high enough to be out of your hearing range.
The tricky part with an HFI wizard is that it uses two different phenomena to track motors. Saturation of the stator which doesn’t care about the saliency (or Ld Lq diff) but only what kind of iron the stator is made of and how concentrated the magnetic fields are in the motor. Probably we could devise some kind of open loop current impulse test and observe the change in flux linkage to estimate this.
Having not enough saturation at a given HFI start voltage and frequency is why you can see the motors start in the wrong direction with HFI. The saturation of the stator is not dramatic enough to produce an observable difference in current. More samples to average, more voltage, and lower frequency should generally improve the observability of that signal.
Then the other part is saliency based and requires the motor to have changing saliency as the magnets rotate over the poles. Not all motors have this it depends on the geometry and materials used. That part I think we could use some kind of distribution to determine how much HFI voltage produces a stable and observable waveform there.
The tricky part really becomes that the saturation and the saliency signal become overlapped and depending on how you drive the motor you muddy the signal of the saliency. That is why at high impulse currents you can see HFI lose track of the motor. The 45 degree version actually exploits this and uses the increasing saturation signal to continue following. It’s all quite an interesting problem. Really cool stuff.
But we would need to make a series of tests to measure each of these behaviors and scale appropriately. I think step one is some type of simple parameterized model to predict the HFI behavior with lumped parameters. If we had something like that which could roughly estimate the expected HFI waveforms we would be most of the way toward finding good HFI parameters.
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I’ve been hearing horror stories about fw.6 shfi and the Stormcore 60d+(which is what I have).
I’m having some standstill start shudders with my HFI on 5.2 and was hoping fw.6 might offer a solution.
I can only speak from my own experience, and my 60d+ on sHFI was fantastic once I lowered the HFI gain parameter to like 100 or 120, instead of the default 300. It was good enough and quiet enough that I wouldn’t bother replacing a motor with broken sensors.
Regular HFI sucks for torque and is loud as hell. You can make it cog and fail very easily on flat ground launches. sHFI handles a lot more amps.
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@Shadowfax Well any chance you’d help a brother out with some settings haha?
I’m running flipsky 63100 140kv.
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I used HFI defaults except for lowering the HFI gain.
Which of the new ones did you you use? VCC, 45 degree silent…etc
Ah ok great. What gain value?
Are you still keeping gain value at .13?
I was using different motors, so I wouldn’t expect our settings to be the same. I don’t know how well flipskys work with HFI or sHFI. I have no experience with them.
Try it out a few different gain values and see what works well for you.
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Yeah I took that into account, but thought I’d try your baseline value and see what happened haha
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Sensors on my MTB died. Not sure how, probably water inside the motors.
I’m using Flipsky BH 6384 140KV motors.
I tried the sensorless modes on my Trampa Vesc 6 mk3 ESCs. Terrible cogging.
Then switched to a Stormcore 60D+. Turning the HFI gain value down to 0.1 and using 45 degree HFI gave me good results. I definitely don’t have as much current from standstill as I’m used to, but at least it starts up without issue. On flat ground. In the snow I required a lot of current to start going, and it wasn’t that smooth. It also cogged once as I quickly switched directions from braking to accelerating. When the snow melts I will test on better offroad terrain and some hills.
Makes me wonder if I should get some external encoders, or buy some fancy Trampa mk6 ESCs to make my MTB perfectly rideable again 
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i found the voltage filters to provide no better sensorless performance
try cleaning your hall sensors as corrosion can cause false signals
I’m on a DV6 (phase shunts) running no sensors at all with Flipsky 6354 140kv motors, allegedly “custom”
Tried running VSS and things are stuttery as heck under load. Freespinning it seems fine. It doesn’t like going backwards with Hyst reverse, just jitters like crazy.
And I’m getting a noticeable power loss after launch, like I feel high torque getting up to speed but then it seems my motors actually slow down. I don’t have a log for this yet but I’ll get one soon.
What are my options and what should I do? I don’t mind the HFI “beep” but I don’t want to run sensors at all, and I want to be able to get up to speed and brake reliably. I also don’t mind kick pushing off as I’m not using bindings.
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Try running Silent HFI 45 deg v0v7.
Im on 60d+/FS6374 and had to turn hfi gain down to .100 from .300.
Its been butterly smooth so far, but its winter and only have 25mi on it.
VSS wasn’t very smooth for me.
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