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Discussion Starter #1
Has anyone else got the latest Leaf Spy Pro downloaded and had a play with the new motor/regen page?
In version 0.31.31 go in to settings and at the bottom in the peach debug section enable "brake and motor screens". If you succeed in not crashing your Leaf whilst watching the rolling graphs you might learn a hell of a lot about the brake pedal and its relationship to regen which is very useful for hypermiling if true :D!

It is counter intuitive and I have already modified my driving style believing in Turbo 3 and the fine canbus data in contrast to the grainy and dotty leaf cockpit data.
Please check it out (you won't be disappointed) and post your opinions here.
Stay safe, get a co-pilot whilst testing :cool:.
Thanks in advance. Hope that helps:).
 

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Likewise, I have an irrational fear of android devices ;)
 

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I was playing with it last week. Apart from all the jiggery pokery it does balancing the friction and regen breaking. It was very interesting how you can sometimes end up with power still going to the motor when stationary with the foot brake on
 

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Discussion Starter #5 (Edited)
Here are a couple of historic (not driving) screen shots off my Android jelly bean 4.2 S4 copy which help explain what the fuss is all about and does this have the potential to create one hell of a fuss :cool:. Whilst your foot is on either pedal the top empty white bar is dynamic and fills from left to right with motor power in blue on the upper page and green and red showing brake pedal only regen and friction braking respectively on the lower page. Both graphs move from right to left across the screen in real time of seconds. Brake and regen only move during a brake pedal application. The brake force applied is the T value and is very accurately progressive to 200 units of fine detail of pressure on the pedal. The motor full power reads from the bottom of the screen up to the blue zero line (a bug) but is also measuring foot on pedal pressure in fine detail.
You can freeze each page as with the others at the push of the green connected button which turns blue when frozen. All data can be logged and fed in to a computer for later. Pretty good eh?
Lessons learned so far;
1...Put in in park or waste creep energy (all red on brake pedal application but blue motor power being consumed...not shown on energy clock!).
2...Don't expect useful brake pedal applied regen below about 15 mph (all red).
3...Don't expect regen with light touch brake pressure (ignore the extra dots, all red on brake pedal until about 20+kw regen shows on car....blimey!)
4. Drive to maximise green and minimise red.
Canbus doesn't lie, Turbo 3 is a genius IMO, All manufacturers tell porkies and like you to feel good by tailoring cockpit displays (dots and energy screen). This is totally unbelievable and counter intuitive but a real indication of how the car really works and so should be driven if, as I have no reason to doubt, it is telling the truth.:) See four dots and a circle bottom left of phone screens signifying tap to select extra new page.
Screenshot_2014-04-27-22-37-08.png

Screenshot_2014-04-27-21-38-39.png
 

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This all seems to tally with my driving experience, no big surprises there really. You can feel how things are working for the most part, ie the car is trying to "pull"/creep if not in P/N with the brakes applied, the lack of regen at low speed (even reflected on my LEAF dash) and other things this data appears to confirm.
 

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Discussion Starter #7
This all seems to tally with my driving experience, no big surprises there really. You can feel how things are working for the most part, ie the car is trying to "pull"/creep if not in P/N with the brakes applied, the lack of regen at low speed (even reflected on my LEAF dash) and other things this data appears to confirm.
Yes we would expect some of that I agree but maybe I failed to make the most important point in my post. The dots, whilst they show some regen under braking are apparently lying through most of the speed regime and are way more optimistic than the canbus readings!
 

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Yes we would expect some of that I agree but maybe I failed to make the most important point in my post. The dots, whilst they show some regen under braking are apparently lying through most of the speed regime and are way more optimistic than the canbus readings!
Do you mean in general, or at very low speed? Mine doesn't show regen dots when braking from very low speed.
 

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Discussion Starter #9 (Edited)
Do you mean in general, or at very low speed? Mine doesn't show regen dots when braking from very low speed.
In general. There is a low speed cut off point as you say, I didn't expect to find it giving canbus readings of regen in that low speed end. Probably for driver braking finesse and maybe lack of any real beneficial gain and to stop the disks rusting:p, friction brakes are doing all the work in that regime.

The big surprise is that at higher speeds say 10mph upwards, both the regen dots and the energy screen seem to over sell the actualiteit and by quite a noticeable margin. If you were to watch the fine detail canbus sampling of a brake regen event on Leaf Spy you would see that all "normal" use of brake pedal during driving, even when not eco driving, results in an almost totally red friction only dynamic bar at the top and it is only when braking hard i.e. sporty spirited driving that you see a majority green colour for regen take over (still often led by red as the dynamic bar shows both colours at once) , and from my experiments so far that is only when the energy screen dial gets to around a whopping 20kw regen which is 2/3rds of the max30kw.

If this is right, the brakes are always being led by friction brakes and not regen effect unless you stamp hard on the pedal initially. That is what is counter intuitive as I think we all assumed it was the other way around?
That's why I asked if anyone else can chime in with their observations to avoid me now driving like a boy racer for max (brake regen) efficiency or I will be fitting a maga exhaust next to match the new driving style:D. Somebody please help.
 

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What about not braking, but just lifting off in either B or D modes? The LEAF shows (and feels like) regen is in effect in both scenarios, and ramped up in B mode (as you'd expect), is that what LEAF Spy reflects?
 

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Discussion Starter #11
What about not braking, but just lifting off in either B or D modes? The LEAF shows (and feels like) regen is in effect in both scenarios, and ramped up in B mode (as you'd expect), is that what LEAF Spy reflects?
That info is not shown on the new page, it is called motor and braking, you are right to ask, it would be good to be able to read that too. On the graph I posted of the braking page, Whilst driving normally on a motorway there may be nothing on it (no brake pedal application), the graph only moves from right to left whilst the brake pedal has some pressure applied. The graph shown is during a pedal pressure application test which happens to exceed 30 seconds on a local empty rural road with a variety of long hill slopes and bends useful for the purpose.
B mode and D mode exhibit the same red friction brake readings off the canbus.
 

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Hmm, without factoring the "lift off" regen braking (and impact of B and D mode) then maybe it's painting an unclear picture, as it's only factoring half of the overall rather complex equation?
 

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Discussion Starter #13
Hmm, without factoring the "lift off" regen braking (and impact of B and D mode) then maybe it's painting an unclear picture, as it's only factoring half of the overall rather complex equation?
Good thinking Paul. I thought of that too and stuck in in Neutral to eliminate any cross error. The same readings still apply with no non pedal regen involved.
 

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I have to say that all this surprises me somewhat. If you look at the kWh remaining figure on LeafSpy when braking from high speed, or even better, when going down a long hill with braking, then the kWh figure definitely increases more quickly with braking over not braking... even gently if my impression is correct.

That seems to be at odds with your suggestion that there is little regen at low to moderate brake pressures doesn't it?

I do know that there are times when regen does some funny things if you believe the dots. Either coming on very low (1 dot) or coming on initially and when lifting and reapplying brake pressure immediately not coming on or only one dot when you have plenty of speed and moderate pressure. It does seem to have a mind of its own :)
 

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If you look at LeafDD (which updates super fast) you can see the actual amps going into the battery during braking. It behaves how I'd expect.

I can't find the chart now, but I do seem to remember the Nissan strategy is, lift off = a bit of regen, as soon as you touch the brake pedal you get some friction, and as you push harder you get a blend of friction and regen.
 

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I have to say that all this surprises me somewhat. If you look at the kWh remaining figure on LeafSpy when braking from high speed, or even better, when going down a long hill with braking, then the kWh figure definitely increases more quickly with braking over not braking... even gently if my impression is correct.

That seems to be at odds with your suggestion that there is little regen at low to moderate brake pressures doesn't it?

I do know that there are times when regen does some funny things if you believe the dots. Either coming on very low (1 dot) or coming on initially and when lifting and reapplying brake pressure immediately not coming on or only one dot when you have plenty of speed and moderate pressure. It does seem to have a mind of its own :)
The roads near me are terrible, I can feel "something" happen when going over rough ground, and looking at LeafDD the amps going into the battery have dropped or stopped (but sometimes the dots are still there) but I am still slowing down. My old prius was the same, except there was a noticeable delay in it taking away the regen force and adding extra friction force.
 

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Discussion Starter #17 (Edited)
I have to say that all this surprises me somewhat. If you look at the kWh remaining figure on LeafSpy when braking from high speed, or even better, when going down a long hill with braking, then the kWh figure definitely increases more quickly with braking over not braking... even gently if my impression is correct.

That seems to be at odds with your suggestion that there is little regen at low to moderate brake pressures doesn't it?

I do know that there are times when regen does some funny things if you believe the dots. Either coming on very low (1 dot) or coming on initially and when lifting and reapplying brake pressure immediately not coming on or only one dot when you have plenty of speed and moderate pressure. It does seem to have a mind of its own :)
Yes I agree, for me the big question is whether or not we now have a mind reader.
M1aws has introduced the idea that a super capacitor could be slewing the figures and playing a part in this. My understanding would be that it is presumably loading up quickly and discharging slowly to the battery. That could account for the missing regen if Leafspy readings are taken after the S.C. has loaded up.
 

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Discussion Starter #18
The roads near me are terrible, I can feel "something" happen when going over rough ground, and looking at LeafDD the amps going into the battery have dropped or stopped (but sometimes the dots are still there) but I am still slowing down. My old prius was the same, except there was a noticeable delay in it taking away the regen force and adding extra friction force.
Yes I think I have experienced that. Why would the regen be effected by g shocks though? Maybe it is automatically instantaneously cut out if the anti skid kicks in and that is very sensitive! That would explain it.
 

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Yes I think I have experienced that. Why would the regen be effected by g shocks though? Maybe it is automatically instantaneously cut out if the anti skid kicks in and that is very sensitive! That would explain it.
Yes exactly. Don't know all the detail but shocks/slips could mean damage to the electric motor if large amounts of power are being applied/regenned, so it protects the motor and increases friction braking.
 

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Interesting. I have also noticed regen drop to zero when hitting a big bump/pothole etc. It generally doesn't come back too quickly after either for that braking event.
 
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