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80 miles in

 I'm really happy with the car as a whole, there's a few things I'd like to try and improve in terms of drivability. I currently have to use 1st gear to get rolling the switch to second for up to 65mph.

I'd love to be able to just leave in second and do 0-70 with reasonable torque. I'm hoping I can tweak a few parameters in the Open Inverter Field Oriented Control software to achieve this. If not, I'll have to liven with it or change to a larger motor, such as the Outlander rear motor that can apparently generate 190NM of torque vs the 135NM of the front, which I have. Another option is to combine both the front motor and generator, reusing the outlander front transaxle/gearbox and replacing the Beetle gearbox.

I've had to make some changes to my charging control code, after doing something silly and blowing the main 250 amp fuse, welding a contactor and destroying an inverter. I did have code to stop the charger for pulling current if the inverter has disconnected the battery. So the charger carried on trying to push out the set current, causing the output voltage to increase to 420v and charging up the large main capacitor. Which as soon as the inverter started back up it saw the voltage above threshold and closed the contactors allowing the main cap to discharge very (very) rapidly, this huge current spike welded the main contactor closed.

To cut a long story short. A new inverter (from a Yaris this time £20) and an upgraded main fuse and more beefy contactors are in and have been in service for the past few hundred miles.


Next up, we need heating, winter's coming.

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