Charger Efficiency comparing 110 and 220

drees said:

..I know that even regular computer power supplies are very often at least a couple percent more efficient when running on 220 vs 120 and they are only converting AC to low voltage DC.

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Actually, most of them boost 120 and 240 to the same high DC voltage (300-400v) using a power-factor-correction (PFC) circuit, probably similar to what's in the Leaf's charging system. The relatively fixed high DC voltage is then converted to low voltage DC.

I2R Losses in the PFC circuit are reduced at higher input voltages (240v).


Charger operates between 260-400V and change, DC

DeaneG said:

drees said:

..I know that even regular computer power supplies are very often at least a couple percent more efficient when running on 220 vs 120 and they are only converting AC to low voltage DC.

Click to expand...

Actually, most of them boost 120 and 240 to the same high DC voltage (300-400v) using a power-factor-correction (PFC) circuit, probably similar to what's in the Leaf's charging system. The relatively fixed high DC voltage is then converted to low voltage DC.

I2R Losses in the PFC circuit are reduced at higher input voltages (240v).


Charger operates between 260-400V and change, DC

Click to expand...

any info on the differences in efficiency?

DaveinOlyWA said:

..any info on the differences in efficiency?

Click to expand...

It depends completely on the design and usage of the particular circuitry. We'll only know for sure once several people have measured both 120V and 240V charging. Since the efficiency change should be fairly small, we'll probably only get useful results if one person measures both values with their own particular charging and vehicle use patterns. There are enough EE's on this forum that we should get the info pretty soon.

ya, well was hoping someone who could effectively measure his charging via 220 would have chimed in. obviously not as easy to do as one would guess.

i wonder what the efficiency of my KAW is? its advertised at .2% so i guess that is pretty accurate.

The output is 260-410 DC.