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Hi guys,


First time poster here so be gentle...


I have a Gen1 Nissan Leaf 30Kw and I want to increase the available power. I was inspired by Arlin Sansome's videos on Youtube:
https://youtu.be/S6OInkLWAhk


I like the idea of potentially creating a bolt-on kit that anyone can purchase and install (at their own risk ofc). Initially though, I just want my Leaf to have a bit more poke. It's my understanding that the stock Leaf motor is capable of way more than the circa 100HP it's developing now. So I imagine it's the controller and batteries that are the limiting factors.


So, I'm thinking of augmenting the batteries with an ultracapacitor and upgrading the controller/invertor. Ideally, I'd like to keep everything else pretty much as-is.


My questions are:
1. Is this even faesible?
2. Would it cost an absolute fortune?
3. Does an Ultracapacitor just sit in-line between the battery and controller or does it need some sort of active management?
4. How faesibile is it to get an uprated controller integrated with the existing Nissan parts?
5. Has anyone seen this type of thing done already?


Thanks in advance,
Craig
 

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Hi Craig
Forget the ultracapacitor - what you need is a new "brain board"

Nissan parts will give 100 hp for 200,000 miles with low warranty failures

If you are willing to drop the reliability then all you need is the brain board to tell the Nissan bits to go for it a bit more

https://pandspowerelectronics.ecwid.com/#!/P&S-Circuit-Boards/c/16287307/offset=0&sort=normal
looks like the store is closed. Any other vendors selling anything along these lines or links to where I can read up more on them?
 

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looks like the store is closed. Any other vendors selling anything along these lines or links to where I can read up more on them?
I am not sure Paul supports field weakening. This is essential for high revs. But if you want to use transmission up to 7000rpm then you are good with his power stage.

Check out Arlos power stage
https://endless-sphere.com/forums/viewtopic.php?f=30&t=63982&p=963227#p963227

And Johannes hijacking of original Leaf inverter AND other inverters with his brain...
https://openinverter.org/forum/viewtopic.php?f=4&t=138&start=60
 

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What about modifying the CAN message that the VCM sends to the Inverter? It should be really easy to do with say a Muxsan CAN-bridge?
 

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Honestly, you would make a heap of power with the Leaf Inverter stock as the IGBTs are rated for 600 Volts and 600 Amps. That's 360 kW, or 482 HP. But I wouldn't even think of straining the Inverter like that unless I had some cooling. Me personally 280-300 HP (209-224 kW) is what I'm aiming for with my Leaf motor. Hopefully I can achieve that with just CAN control. Never done SMD soldering until I started working on Damien's VCM board, but I feel I'm getting better with each component I solder on.

Sent from my G3223 using Tapatalk
View attachment 114525
 

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I'm pretty sure the Leaf's power output is limited by the batteries. Whether that's due to heat or chemistry, I dunno...I haven't been able to find specs on how much current the motor draws at full throttle and how much current each module can deliver.
 

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I'm pretty sure the Leaf's power output is limited by the batteries. Whether that's due to heat or chemistry, I dunno...I haven't been able to find specs on how much current the motor draws at full throttle and how much current each module can deliver.
Yes after 2500rpm inverter starts reducing torque to remain in the 80kw power limit. I also think this is mostly because of battery motor power declaration. Legal... I think battery can safely withstand 300A.

If you keep max torque 280Nm up to 4000rpm you would get 115kW which is also the power limit of the new 2019 leaf.

Then if you keep 280Nm up to 7000rpm which is approx the motor voltage limit without field weakening you would get 200kW. Now that is a lot of power and incidentally some 360V 600A limit on transistors. I think 200kW is a good bet for max power on this motor, but for only a 30s burst on most controllers. Not that motor would complain, transistors inside inverter need to be cooled.
 

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So, how do we develop something for the bone stock leaf?


1. I've read that the Leafbox (yeah don't get me started on how overpriced neutral pedal mapping can be so revolutionary) could also increase the Leaf power output from 80kW -> 84kW. So there is maybe some buffer in the pedal signal? Maybe we could hijack this and when the trottle is applied to full, just write the can message to whatever the bit above full throttle is. Might be a lot of work for only 4kW, but potentially doable


2. The second way is to cut the CAN between VCM and Inverter, and modify the key messages. Anyone willing to help out here? I have access to muxsan CAN boards, so should be straightforward to try either #1 or #2
 

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Hm... Maybe one could listen with Savycan on CAN bus and reference what the pedal position is and what Leaf brain is commanding inverter to do.

From Ampera (2013 Volt) i know when you apply sport mode you actually dont increase power. What this does is shift throttle curve to provide more torque at lower end of the RPM. The car seems more powerfull that way and in the end you dont need much torque at the 10KRPM to step over 80kW limit.

So there it is your solution for low end power.
1. Put a CAN filter uC on CAN lines between brain and inverter.
2. Filter out the torque demand IDs. Those are published.
3. After filter connect one uC that will read throttle position and calculate what data MSG to output.
4. Test drive!

Maybe you could get away with not cutting the wires. You would just have to time nonsuspecting CAN ID of torque and transmitt the CAN ID with your data just before so inverter decides to listen to yours instead of original. I think there is some requirement how fast throttle signal is transmitted. If you send duplicate ID original will get filtered out as an echo...
 

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Hm... Maybe one could listen with Savycan on CAN bus and reference what the pedal position is and what Leaf brain is commanding inverter to do.

From Ampera (2013 Volt) i know when you apply sport mode you actually dont increase power. What this does is shift throttle curve to provide more torque at lower end of the RPM. The car seems more powerfull that way and in the end you dont need much torque at the 10KRPM to step over 80kW limit.

So there it is your solution for low end power.
1. Put a CAN filter uC on CAN lines between brain and inverter.
2. Filter out the torque demand IDs. Those are published.
3. After filter connect one uC that will read throttle position and calculate what data MSG to output.
4. Test drive!

Maybe you could get away with not cutting the wires. You would just have to time nonsuspecting CAN ID of torque and transmitt the CAN ID with your data just before so inverter decides to listen to yours instead of original. I think there is some requirement how fast throttle signal is transmitted. If you send duplicate ID original will get filtered out as an echo...

Nah, spoofing messages by spamming is not an option. The LEAF has built in error checking in the format of P-RUN messages. In my repo you can see which ones have this on the EV-can for instance. https://github.com/dalathegreat/leaf_can_bus_messages

"PRUN: Detection of frozen data. Message-PRUN-Diag. The transmitting node adds a message counter of 2bits or more to the end of the last data area (or just before the checksum). The value of the counter, which is initially 0, increments by one everytime new data is transmitted, and returned to zero when reaching the max value. The receiving node lets the first message pass without check, but for second next message and following, it check whether the counter number is different from the previous message."

So it's not possible to spam, cut wires and re-calculate is only option.
 

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In my repo you can see which ones have this on the EV-can for instance.
This is great! To what level of completeness has the Leaf protocol been sussed out? I've seen the spreadsheet this is built from, but I'm new to CAN and it doesn't seem like you could, say, control a charger, BMS, or DC-DC converter from the info.

The longass thread on the Leaf forum is pretty dead these days. Where is most Leaf/CAN hacking being discussed? I'm hoping to get to a point where someone could buy an Arduino, install some open-source software, and control Leaf components (thereby saving 10x vs aftermarket parts).
 

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This is great! To what level of completeness has the Leaf protocol been sussed out? I've seen the spreadsheet this is built from, but I'm new to CAN and it doesn't seem like you could, say, control a charger, BMS, or DC-DC converter from the info.

The longass thread on the Leaf forum is pretty dead these days. Where is most Leaf/CAN hacking being discussed? I'm hoping to get to a point where someone could buy an Arduino, install some open-source software, and control Leaf components (thereby saving 10x vs aftermarket parts).

The EV-CAN on 2011-2017 Leafs are very well documented. But as you say, this does not allow you to control DC-DC converter from this info. But it does allow you to do some crazy good things like;
-Install any Nissan battery you want into any Leaf

-Increase charging speed when you have installed a bigger battery
-Make custom stop charging at XX% SOC commands
-Etc.


Most of the CAN discussion is happening on private e-mail chains. This is because people are willing to pay for these features, so everything cannot be freely shared yet. Everything I find out I'm making open-source, but I can't do the same with other peoples findings.


Forget the Arduino, you need a proper CAN-gateway. It's still quite cheap, and once we strap these CAN-bridges onto other busses, there is performance to be had :)
 

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Hi Dala!

I'm currently playing around with leaf motors (see bbitnerblogs.com/e-miata)
and have found that http://productions.8dromeda.net/c55-leaf-inverter-protocol.html
seems to have pretty accurate information. I believe that there may be two typo's
in that document. 1, minimum voltage is 240, not 140. This is backed up by the
Nissan fault codes. 2, I think msg 1DA is 2 volts per increment. Not sure about RPM's
yet. We will also be open-sourcing our software to make this run. Currently, I don't have
a big enough power supply to spin the motor, but I"m building batteries and looking into how to make the leaf charger do the job (from a hardware perspective, not CAN messages).
 

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Hi Tremelune!

The motor itself does not. In fact, I think I saw someone run the motor on 12 volts using
Johannes Hubner's (https://openinverter.org/docs/index.html?en_home,3.html) logic board and using the leaf inverters power stage. What I'm talking about is using the
factory inverter with no modifications. As far as documentation for the 240 volts, it is
in the service manual as a trouble code. I can look it up if you need it. I seem to recall that you modified the inverter by replacing the logic board, so you won't have that restriction. :)
 

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Oof, I did not! I'm using Thunderstruck's controller, but that just talks to the inverter, so it sounds like I'm under the same constraint. I might have to add another 6 modules!

Off to research...
 

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The information from Nissan is in the tms.pdf file (don't remember where I got that) on page 24, where they state the normal operating voltage is 240-403. It can go as high as 500 while in regen, but shouldn't go higher. I don't know anything about the thunderstruck board. I hope it works out ok for you.. Best of luck.
 
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