whats the max kW on the em57 with the open inverter board?

[papasapien]

anyone ever test it with different batteries? is there a set limit as of now, just from a software stand point? are there any other inverters/controllers for it with higher kW capabilities?

[johu]

There is only a board for gen2 inverters which have been reported to output 136 kW with a tired 24 kWh pack. So probably more in it with better batteries and slightly higher voltage.
There is a gen3 version of the inverter which can output 160 kW with the stock inverter board but so far we have only managed to get 125 kW from it. Probably not a big thing to change.

The gen3 OI board never got developed because there probably won't be much demand for it.

[Jacobsmess]

There is only a board for gen2 inverters which have been reported to output 136 kW with a tired 24 kWh pack. So probably more in it with better batteries and slightly higher voltage.
There is a gen3 version of the inverter which can output 160 kW with the stock inverter board but so far we have only managed to get 125 kW from it. Probably not a big thing to change.

The gen3 OI board never got developed because there probably won't be much demand for it.

I'm curious, why would the demand be low for a higher power and newer inverter?

[johu]

I'm curious, why would the demand be low for a higher power and newer inverter?

Because the OEM control board can already output 160 kW
Plus the demand for OI Nissan control boards isn't high in general because these can just be used with CAN without needing to swap the control board.

[papasapien]

Because the OEM control board can already output 160 kW
Plus the demand for OI Nissan control boards isn't high in general because these can just be used with CAN without needing to swap the control board.

i thought you said it only can output 125kW as of now? is that using the OI board right? but without using the OI board you can get 160kW? why would anyone use the OI board if you can get 160 stock?

[johu]

Summary:
- Gen2 with OEM logic board: 80 kW
- Gen2 with OI logic board: 136 kW
- Gen3 with OEM 160 kW logic board: 125 kW - with correct CAN message 160 kW
- Gen3 with OI logic board: unknown

[jrbe]

If you can use a different power section the em57 em61 has been dynoed at 302hp / 222kw at the wheels on a claimed 460v pack. Not sure of pack droop while doing that or dc current draw.
So your pack voltage x .48 should give you approximate kw for an em57 em61 (at the wheels) if it can supply the current. *edit* this is a very rough / theoretical number that is assuming the inverter can supply this power and is also assuming the motor isn't saturated.

*edit* not sure how much lower an em57 would be with the same battery / inverter as an em61. I'm not aware of any back to back comparison between the 2.

Seems the Prius inverter could do this if the boost converter is bypassed and mg1 & mg2 are combined.

[lsh3rd]

That 302hp number makes me think you are referring to Arlin Sansome's CRX - he did use an EM61, not an EM57. I think the EM61 has a bit more power potential.

[jrbe]

That 302hp number makes me think you are referring to Arlin Sansome's CRX - he did use an EM61, not an EM57. I think the EM61 has a bit more power potential.

Yeah, Arlin's dyno #s. I misread a post from him, thanks for the correction. I'll edit my previous post.

[Jacobsmess]

If you can use a different power section the em57 em61 has been dynoed at 302hp / 222kw at the wheels on a claimed 460v pack. Not sure of pack droop while doing that or dc current draw.
So your pack voltage x .48 should give you approximate kw for an em57 em61 (at the wheels) if it can supply the current.

*edit* not sure how much lower an em57 would be with the same battery / inverter as an em61. I'm not aware of any back to back comparison between the 2.

Seems the Prius inverter could do this if the boost converter is bypassed and mg1 & mg2 are combined.

Hmm I do like the idea of big power from an em61/Prius inverter setup.... I assuming bypassing the boost wouldn't be an issue as per the lexus 450h approach... How would one combine mg1/mg2 power output? Just a junction box for the wires?

[jrbe]

Hmm I do like the idea of big power from an em61/Prius inverter setup.... I assuming bypassing the boost wouldn't be an issue as per the lexus 450h approach... How would one combine mg1/mg2 power output? Just a junction box for the wires?

Info in the wiki, I'm still working through this myself.
https://openinverter.org/wiki/Toyota_Pr ... ngle_motor

Gen 2 Prius inverter is an option (I think..) as well. It doesn't seem to be as clearly wiki'd as the gen 3 is though.

I'm probably missing something obvious but I haven't found clear info on how to bypass the buck / boost converter yet. Do you have a link to that method for the 450h?

[Jacobsmess]

Info in the wiki, I'm still working through this myself.
https://openinverter.org/wiki/Toyota_Pr ... ngle_motor

Gen 2 Prius inverter is an option (I think..) as well. It doesn't seem to be as clearly wiki'd as the gen 3 is though.

I'm probably missing something obvious but I haven't found clear info on how to bypass the buck / boost converter yet. Do you have a link to that method for the 450h?

It's well documented in Damian Maguire's videos on the gs450 and 300h but you basically pop off a plastic cover and connect to your bus bars that bypasses the boost stage. This means the inverter no longer outputs 650V as I understand and instead is at the battery voltage but providing rpm isn't a limiting factor for you, it shouldn't be an issue.

[Zieg]

So is the thinking then that the Prius inverter can put more kW through an EM57 than the stock inverter running an OI board? And why bypass the boost stage? Even if you don't need the peak RPM, wouldn't it help you maintain torque into higher RPM?

Sorry, genuinely curious so thought I'd better ask.

[Jacobsmess]

So is the thinking then that the Prius inverter can put more kW through an EM57 than the stock inverter running an OI board? And why bypass the boost stage? Even if you don't need the peak RPM, wouldn't it help you maintain torque into higher RPM?

Sorry, genuinely curious so thought I'd better ask.

Boost stage gets bypassed because it blows IGBTs at the higher current levels from what I understand.

Re: leaf vs. Prius inverter, I'm not sure but asked a similar answer and got a complicated answer.

[Jacobsmess]

So is the thinking then that the Prius inverter can put more kW through an EM57 than the stock inverter running an OI board? And why bypass the boost stage? Even if you don't need the peak RPM, wouldn't it help you maintain torque into higher RPM?

Sorry, genuinely curious so thought I'd better ask.

viewtopic.php?p=56703&hilit=Prius+inver ... eaf#p56703

Read here for leaf Vs Prius inverter setups

[Zieg]

Huh, interesting. I wonder if that comment about current output is out of date now? If MG1 and 2 can be paralled I'd think it'd be a higher overall output. Guess that only really helps if you're not traction-limited, though.

[jrbe]

So is the thinking then that the Prius inverter can put more kW through an EM57 than the stock inverter running an OI board? And why bypass the boost stage? Even if you don't need the peak RPM, wouldn't it help you maintain torque into higher RPM?

Sorry, genuinely curious so thought I'd better ask.

My understanding is the boost stage can't support very much power. It's used in the oe Toyota setups to boost the battery voltage but at quite limited power levels.

Toyota seriously overbuilt the power section compared to the boost converter. Bypassing the boost converter with a decently high voltage battery level allows the power stage to be used more to it's capability.

The oe leaf inverters current power levels are listed in johu' s post a few previous.

- Gen2 with OEM logic board: 80 kW
- Gen2 with OI logic board: 136 kW
- Gen3 with OEM 160 kW logic board: 125 kW - with correct CAN message 160 kW
- Gen3 with OI logic board: unknown

I believe the Prius inverter can supply more than the Nissan leaf inverters can currently (and maybe more than they would max out - to be determined) but I haven't confirmed that myself yet or found any clear evidence.

[Jacobsmess]

Huh, interesting. I wonder if that comment about current output is out of date now? If MG1 and 2 can be paralled I'd think it'd be a higher overall output. Guess that only really helps if you're not traction-limited, though.

See Johus response for the max current, it seems when running both it is limited to 2/3rds of mg2

[johu]

Keep in mind the numbers stated are actual figures from real cars, not "lets multiply volts with amps".
On the other hand these figures were determined with old firmware, so it is well possible that with nowadays improved firmware more than 136 kW can be had. It is certainly not an absolute maximum.