Troubleshooting WB Projects' E Turbo

I tought that I was clear sorry. Second graph ( internal battery voltage in light blue), third (input voltage in orange), fourth (input current in orange and peak current in purple), fifth (motor rpm x100 in green) and the last one (incoming power in watts in light blue)
 
Yes it is! I will do a lot of work in the winter on the battery and make it work with RPM! Long story short, for an example, my tuner want me to add more boost a 4800rpm because I start lousing torque. But right now If I want more boost at 4800rpm I will have more boost on all the power band.. so I will need your help with programming the Arduino and the cherry hall-effect sensor! The capacity of the battery look good at the end but the voltage drop is to big. I can get bigger cable but I don't know how much this will help.
 
WB projects said:
Yes it is! I will do a lot of work in the winter on the battery and make it work with RPM! Long story short, for an example, my tuner want me to add more boost a 4800rpm because I start lousing torque. But right now If I want more boost at 4800rpm I will have more boost on all the power band.. so I will need your help with programming the Arduino and the cherry hall-effect sensor! The capacity of the battery look good at the end but the voltage drop is to big. I can get bigger cable but I don't know how much this will help.
Click to expand...

Yeah im along way though programming it .. i wont be using or recommending a hall affect sensor though as that makes no sense. You might as well plug it into cam angle sensor... and the pedal sensor while your at it.
 
Why getting an hall affect sensor makes no sens? For me, tunning the car and adding boost through différents RPM seams a really good idea
 
Ok. Sorry, I was tied up last night and had a very long video call with Frank from Trampa (VESC) this morning - he's in Berlin and I'm in DC. For me it was the start of the day and for him the end of the day & I wanted to be able to study your graphs in detail. So are you still experiencing the surging? Or were those just short pulls? If they were, what did you do to cure the surging? Were you just triggering the e turbo higher in the RPM band? What is the difference between battery internal voltage vs. input voltage? I have alot of questions, lol. Answer those (as many as you can), and I'll be able to give you some of my thoughts, whatever they're worth.

Either way, I'm glad you stuck with your project to get to this point (I'd say I was proud of you, but that would sound paternal and possibly condescending - and I don't what either). Your development contributes A LOT to the e-turbo cause. Thanks.

As for the sensor thing. The actual mechanism - a hall-effect sensor, a tach output (from where?) whatever it ends up being - doesn't really matter. What matters is proportional control with RPM in William's case. It doesn't matter for me because my setup isn't close to going into surge (yet). It actually might if I can get enough RPM on the e turbo. But would have a tach signal avaliable; heck, I have outputs on my EFI computer I could use too. William's car is probably much more representative of what most people will be dealing with. A car with an OEM computer and no distributor. That's where the beauty of a hall effect sensor comes in. It's completely independent of the car's EFI system and 100% transportable from car to car. And much easier to read than a VR sensor - I actually fought that battle on my car's EFI setup and eventually gave up and went to a hall effect sensor. Too much variability in the VR output. (VR = variable reluctance, btw. Easy to make and understand, but has it's own set of problems - notably the output spikes vary a lot in voltage with increasing speed and are prone to noise.)
 
Hahaha thanks a lot Alex I'm proud of myself too and all of this make me go foward faster then doing this all by myself. You all give me more more more idea to solve the problems I had.
Thanks to all of you!

So, the surge problems happen in low RPM. More in 3rd and 4th. As you can see Alex the 2nd gear is harder for the Turbo. Less RPM and less boost then 3rd and 4th gear. You see the last 3 spike in all the graphs? This is a normal WOT pull shifting at like 5k RPM on 2-3 and 4 gear no surge. BUT it's when I start low in 3rd gear that the surge happen. I'll post a link where you can see what I think is a surge of the turbo. Same gear but different RPM
I will talk with Marek about the "out of sink" in some case in 2nd gear but I think is because my battery's not strong enough.
When I tune the car the surge happen less frequently. Maybe because I dont try to boost it at low rpm anymore or the tunning help a bit!
My question for you is: is it normal that is harder to power the turbo in 2nd gear? I thought it would be easyer in 2nd but I have more boost in 4th 😂
 
Sorry i wasn't clear on this
Yes I will do Brushless motor RPM based on car Engine RPM.
What i was saying is there will be no need to ADD a hall affect sensor to your engine somewhere to then read the the engine's RPM because the car already has an optical sensor for reading RPM. Im going to just spice into that wire and use that...
That is not to say that if you WANTED to add an additional Hall affect sensor that you couldn't In the code you can.

WB projects said:
Why getting an hall affect sensor makes no sens? For me, tunning the car and adding boost through différents RPM seams a really good idea
Click to expand...


Well on those sheets the 0.8 is a AC resistance where as i was calculating the DC resistance. ( the real resistance ) on the head way 38120 they have a AC resistance of 3.93 and 2.65 while their DC resistance is 50 and 48 milliohms.

Your "4" (DC) is pretty good actually.

WB projects said:
4.07 mohm and it's "supposed" to be 0.8 😅 are your counting the cable in this?
Click to expand...

Personally i'd recommend you buy one of those handled AC resistance testers and dismantle your battery and check each cell to make sure they are all ok.... then if you want more power add 6 more cells for 50volts unloaded.

Sure you can buy all new cells but without actually testing the ones you have, how would you know if the new cells are better or worse than the ones you have ? you can't trust sellers they will tell you any kind of rubbish.
 
WB projects said:
Hahaha thanks a lot Alex I'm proud of myself too and all of this make me go foward faster then doing this all by myself. You all give me more more more idea to solve the problems I had.
Thanks to all of you!

So, the surge problems happen in low RPM. More in 3rd and 4th. As you can see Alex the 2nd gear is harder for the Turbo. Less RPM and less boost then 3rd and 4th gear. You see the last 3 spike in all the graphs? This is a normal WOT pull shifting at like 5k RPM on 2-3 and 4 gear no surge. BUT it's when I start low in 3rd gear that the surge happen. I'll post a link where you can see what I think is a surge of the turbo. Same gear but different RPM
I will talk with Marek about the "out of sink" in some case in 2nd gear but I think is because my battery's not strong enough.
When I tune the car the surge happen less frequently. Maybe because I dont try to boost it at low rpm anymore or the tunning help a bit!
My question for you is: is it normal that is harder to power the turbo in 2nd gear? I thought it would be easyer in 2nd but I have more boost in 4th 😂
Click to expand...

What compressor housing and wheel are you using ?
The compressor surge when you take your foot off the the gass sounds awesome :)
 
I will be honnest, your LTO battery you show me the other day look perfect. I will wait untill you test it but Im sure I will go with it.. in therm of space I can't really continue to go bigger with the one I have.
 
I use a chinese GT35
Yes it sound awesome but don't think the turbo will be happy with it long therm 😂 I put a blow off this week and but it doesn't work! I will make a final video for this season showing ALLLL the work I've done and explain all of it
 
Well, you have a lot more gears than me, lol. I only have two. Looking at my datalogs, you can see where the shift occurs. Here is the electrical rpm graph:

Screenshot (49).png

So at low rpm, in both first and second gears (the 1-2 gear shift is where the graph rises again), the turbo speeds up a bit. It's not a lot, but it's not insignificant either - it's the difference between about 29,300 impeller rpm and 26,700 impeller rpm. Now the question is, is it drawing more power when it speeds up? Let's look at that graph (I don't know - I haven't looked myself yet!):

Screenshot (54).png

That's power in watts. So there's an initial spike, but then it's less power at lower rpm, rising as rpm rises. Let's look at current:

Screenshot (47).png

Pretty much the same. Now I'm sure you want to see my battery voltage. I don't have those massive spikes you do (probably because of my gigantic capacitor bank):

Screenshot (46).png

Hope this helps.

MkgStffAwesome - in my conversation with Frank this morning, he reminded me that inductance plays a huge role in avaliable power, since we are dealing with essentially an AC motor. And inductance varies with frequency. So even though I was able to measure my capacitors' ESR after the inferno I had (and they seem ok - both giving an ESR of 0.07 milliohms), I don't know what the ESR is at a particular frequency. Just something to keep in mind. But I do think William's batteries have too high an internal resistance, like you suggest.
 
I wish shipping lipos wasn't such a PITA, esp. internationally - I'd just send you some of my old lipos to try. But it would probably cost more than they're worth!
 
In fact, even me when I go up in gear with less power in the battery, the motor spin more and use less power! That's what's botering me why 2nd gear is harder to run 🤷‍♂️ 3000rpm in 4th gear in easyer the the 2nd at 3000rpm, but as the rpm goes up, in both case, the power in watts goes up too
 
Actually, now that I think about it, that actually can make sense. 4th gear loads the car's engine much harder than second gear does. It also accelerates more slowly. So the e turbo isn't able to accelerate as fast in 4th gear as it can in 2nd gear. Maybe that difference in acceleration is the difference in power required in 2nd gear vs. 4th? I dunno. I'm kind of guessing to be honest.

I, too, have a bunch of stuff in my data that doesn't make sense. Like why I'm seeing 340 amps to the ESC but the ESC was only logging 240. Or why running lower voltage (when 1 pack got disconnected) resulted in more wattage draw by 700 watts. Or why I was limited to an 85% duty cycle on the motor... still a lot of unanswered questions, here, fellas.

We'll get there...

Here's an interesting thing to ponder. Let's say you have two gas powered cars. Both make the exact same hp - let's say 500hp. The difference is one makes 500 hp at 5,000 rpm and the other makes 500 hp at 7,000 rpm. Both are geared to run optimally in their power band. If they line up to drag race, who's going to win? All other specs of the cars are the same, and traction isn't a problem...
 
No it's the other way in my case! It's harder for the turbo to spool in second gear then in 4th. 2nd gear pull 6000+ watts and turn at 42k rpm. 4th gear pull arround 5000 watts and turn 49k rpm. Sorry if Im not clear I struggle to explain to myself because it make no sens for me 😂
 
That's what I mean, but I wasn't terribly clear. And that's actually tied in to the question about the 2 500hp cars. The car with the 7,000 rpm hp peak will always win because it has more gear multiplication which allows it to accelerate faster (hp has nothing to do with acceleration, even though it does have to do with speed - hp is a function of torque and speed, but not acceleration - it's a bit confusing). In this case, the e turbo has to work harder in 2nd gear than in 4th gear because it has to keep up with the faster engine acceleration. But if I'm going to be completely truthful, I'm just guessing. Because it's working the opposite way in my car, based on my logs... so the answer is, I don't know. I'm just thinking out loud and it's coming across like I'm pissing in the wind. Which I kind of am, to be honest.

But I do want you to clarify one thing for me - just so I understand clearly - you "fixed" the surging problem by simply activating the e turbo at higher engine rpm in 2nd gear? And when you try activating the e turbo at lower engine rpm in 4th gear, it doesn't surge? That's kind of weird.

Still thinking out loud - since you have a manual and I have an automatic, maybe that plays a role? With the kind of transmission I have - a powerglide - the torque converter is pretty "loose" - so that might be making a difference. In your car, you have direct drive to the wheels...
 
I know I keep changing the claims. I didnt do a lot of test because of the car not fully tune and the ESC not tune too. Anyway Im saying this trying to avoid your pee in the wind ahhaha love your humor 😂
What happen in 2nd gear
I need to activate the turbo arround 2500-3000 rpm to have a nice consistent pull. Over 3500-4000 RPM the ESC will make that weird sound we talk (waiting on Marek thoughts). BUT! It will make a nice consistent pull through all the RPM if im starting at 2500-3000 RPM!

What happen in 3rd and 4th gear
If I try to boost under arround 3000 RPM, the turbo surge. BUT no problems of weird sound at higher RPM (so that's kinda confirm the "to much power (watts) theorie I have")
I hope it start to become clear
The graphs I post of 2-3-4 pull I started the 2nd at 2500-3000 RPM and it goes flawlessly all the way
 
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