Could you use a Prius Gen 3 inverter as an inverter AND charger
- Matthew Dresser
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Could you use a Prius Gen 3 inverter as an inverter AND charger
Because I'm a tight-wad I'm wondering if it's possible to use the same Gen 3 inverter as a charger and inverter? This could save a fair bit of space, potentially and maybe cut down on cabling etc?
Possible, impossible, clever, stupid?
Possible, impossible, clever, stupid?
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- Matthew Dresser
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
I noticed that post, but for me, it wasn't clear if they are using the inverter to control the motor AS WELL AS using it for a charger?
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- jnsaff
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
Gen 3 has two inverters in its housing for MG1 and MG2. In cases where only one motor is used MG2 inverter is used for the motor and MG1 can be used as a charger.
- clanger9
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
Ah, see now you've got me wondering...
A single open-source unit for inverter+charger+dc/dc might possibly work on my bike.
Especially as Curtis still haven't bothered to call me back yet...
What voltage do these things work down to?
A single open-source unit for inverter+charger+dc/dc might possibly work on my bike.

Especially as Curtis still haven't bothered to call me back yet...
What voltage do these things work down to?
Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
I have very similar ambitions.
Damien has done many inverter / motor tests at 12V.

The control logic needs a clean 12V however the power / motor side of the converters can be anything within the voltage and current limits of the power output transistors.
However the 12V DC/DC converter can be sensitive to the input voltage. I've done some work on it but only in relation to fooling it to work on a higher than designed voltage.
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
I managed to get DCDC to work from 100Vdc up to 310Vdc. It can output like 1kW 14V before it drops voltage.
viewtopic.php?f=14&t=51&start=50#p948
My version of EMW - Prius charger interface works on bench. I still have to sort the transistor control here since it sort of stalls on charge command. I am sure it is a problem with PNP/NPN transistor orientation.
Right now i am working on dual motor Volt inverter drive while also developing single motor drive from both sides in parallel. This is taking its toll on my time, so charger is no. 3 priority. Should have it back on dissection by next month.
- clanger9
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
Wow, had no idea they'd go that low! Great to hear the DC:DC is happy down to 100V without modification (though I only need 100W, not 1kW!). If it'll handle ~350A (@128V) on the motor inverter then this could well work for me. Then it's just a case of hacking around with the second inverter to use it as a battery charger. Single, cheap unit and cooling system =
Power factor when charging will be horrible, but that's a separate problem.
Step 1: make a cardboard mockup of the Gen 3 unit and find out if it'll fit anywhere...

Power factor when charging will be horrible, but that's a separate problem.
Step 1: make a cardboard mockup of the Gen 3 unit and find out if it'll fit anywhere...
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
I am sure it will handle 350A no problem.
Well power factor from single phase is attrocious, maybe 65% efficiency there. However i use my charger from 3phase and here PF is not an issue since phase shift is the same on all three phases.

At 600V buck to 100Vdc Transistor will suffer though and you will probably have to see how to handle the heat buildup.
Or you could use 150V....
EDIT: I would recommend at least 120Vdc with DCDC 12V stage. When i tested it at 100Vdc voltage was down to 13V.
- clanger9
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
Thank you! Current plan is for a 32s battery pack (so ~128V). I can probably get away with horrible power factor for home charging on single phase; being able to charge at a decent rate on 3ph AC public chargers would be amazing.
What are the approximate overall dimensions of a Gen 3 inverter?

What are the approximate overall dimensions of a Gen 3 inverter?
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
Something around 14"x14"x8"?
Maybe 16"x16"x10"?
Between toaster size and microwave size.
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Re: Could you use a Prius Gen 3 inverter as an inverter AND charger
i am going to use gen 3 inverter for my two motors, and a gen 2 inverter for battery charging, and possibly single or 3 phase output for house battery backup later on. I have got permission from my mechanical engineer CPENG to install a gen 2 inverter where the muffler smoke box used to be on my e39.