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Chademo is go

 After quite a few trips round to the rapid charger resulting in failure, I finally had success. The code needed some tweaks, the software wasn't sending quite the right messages (the extended flag on the can messages was randomly being set and unset, explicitly setting it to false was needed). 

The charger performed it's checks and then fired in to action.



I'd set the max charge rate at 50 amps for this test, so a nudge under 20kw. This particular charging unit was reporting it was capable of 125 amps and 475V, the logs of this charge show the station ramped up to 50amps and I charged for 5 minutes, as I was only testing. 

The hardware requirements for this are quite minimal, as the heavy lifting is done by the charging unit. I put together a basic shield for the Arduino Due (https://oshwlab.com/jamie84.jj/duechademo) and started modifying the Chademo Control Software from GitHub, my fork is (https://github.com/jamiejones85/CHAdeMOSoftware).



 A couple of contactors are needed, these are overkill for for the job, but I had them laying around. These will connect the battery directly to the charge port, but only when the car and charging station are happy.

Still plenty to do, it's not at a state where I can just roll up and plug in yet, I need to finalise some wiring and modify the software more. I'd like the charger to show the State of Charge as my BMS sees it, also I'd like the additional peace of mind that the BMS can cut the charge rate should the battery be too warm or cold. Again, the BMS should be able to terminate the charge should any of the cells get too far out of balance or over the upper set point.


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