maanantai 15. lokakuuta 2012

Numbers

Some calculations I got to doing somewhere else, but they seem to be worth repeating here.
First a little round-up of power per mass in kW per kg.

GPX750R 750cc..... 0.34
GPX750R electric… 0.14
Aptera 2e………….. 0.10
Xsara 1.8i…………. 0.07
307sw HDi90……… 0.04
Citroën C-Zero……. 0.04

What you can take home from this is that a diesel or an electric car should be fine with 0.04 kW/kg. For the Xsara at about 1200 kg that means about 48 kW is what we want. That comes down to this:

Power... Voltage... Amps
48 kW... 75 V....... 640 A
48 kW... 99 V....... 485 A

Not a huge lot. Almost in the range of a Soliton Jr. with 75 V. With 99 V nominal very much so. With the AXE7245 the theoretical maximum would be 75 V * 450 A ≈ 34 kW. Not quite enough to be a comfortable drive, but perhaps enough to test with. I can't get 450 A from the 40 Ah CALBs though, 300 A might be near comfortable there, which comes down to about 23 kW. I think I'll eventually find out if the car goes anywhere with that little power.

1 kommentti:

  1. I think you will be able to get it moving even allowing for some voltage sag and transmission losses.

    VastaaPoista