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Gearing up to convert an E46 Touring this winter, using a GS450H Gearbox and inverter.

However the 10 Tesla Model S modules I'm also going to use, each have a voltage of 23.2, giving me a total of 232v, whereas the inverter needs a 280v minimum.

Is there a way to boost my pack voltage that little step while retaining regen?
I'm initially thinking buck-boost converter but open to ideas.
 

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pardon my question but, why don't just add another 3 more modules to make up the difference from 232v to 280v? the money on a buck-boost converter would be more worth the extra capacity by adding modules in my opinion. (afaik, high-powered buck-boost converters aren't cheap)

another comment is, if the inverter is 280v min, it means that your battery pack needs to be 280v at min voltage, i.e. your pack should be above that 280v at all operating scenarios. Therefore you should be using the Model S modules min voltage of 19.2v (3.2v x 6s, or somewhere along those numbers), and you'll therefore need 15 Model S modules rather than 10 (15 x 19.2v = 288v which is more than 280v).

lastly, I don't really understand the last part of your question "Is there a way to boost my pack voltage that little step while retaining regen?" so I couldn't really answer this part. maybe if you can elaborate a bit on this then myself or others in this forum can comment.
 

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pardon my question but, why don't just add another 3 more modules to make up the difference from 232v to 280v? the money on a buck-boost converter would be more worth the extra capacity by adding modules in my opinion. (afaik, high-powered buck-boost converters aren't cheap)

another comment is, if the inverter is 280v min, it means that your battery pack needs to be 280v at min voltage, i.e. your pack should be above that 280v at all operating scenarios. Therefore you should be using the Model S modules min voltage of 19.2v (3.2v x 6s, or somewhere along those numbers), and you'll therefore need 15 Model S modules rather than 10 (15 x 19.2v = 288v which is more than 280v).

lastly, I don't really understand the last part of your question "Is there a way to boost my pack voltage that little step while retaining regen?" so I couldn't really answer this part. maybe if you can elaborate a bit on this then myself or others in this forum can comment.
Turns out I was wrong the inverter im using can indeed run under 280v, just with less rpm, no problem for me. someones run it with as little as 12 v
 

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lastly, I don't really understand the last part of your question "Is there a way to boost my pack voltage that little step while retaining regen?" so I couldn't really answer this part. maybe if you can elaborate a bit on this then myself or others in this forum can comment.
I assume that the concern is that the booster might not work in reverse, and so wouldn't allow the motor and inverter to charge the battery during regeneration.

By coincidence, many Toyota hybrids include a voltage doubler between the battery and inverter power stage (integrated into the controller/inverter) so the battery voltage is half of the maximum motor voltage, and they handle regenerative braking.
 
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