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All in one electronics package.
It occurs to me that it would be really handy to combine four items that are in pretty much every EV into one package. Those four items are the Motor control, Charger, DC/DC converter and the State Of Charge device. This would also incorporate the fuse, contactor, precharge electronics, and maintenance disconnect. You could gain a lot from combining all these things into a single unit. Wiring is minimized. For power connections you would have a pair of cables to connect to the battery, a pair of cables to connect to the motor, a cable going to the J1772 charge connector, and a pair of wires to power the 12v car systems. There would be a terminal strip to connect to the on switch, brake pedal, throttle pedal, clutch pedal, cruise control buttons, fuel gauge, tachometer, temperature gauge, motor rpm sensor and any other things I have not thought of. Configuration could be done with an ethernet connection. RS232, or a CAN bus link or USB. You could even have an hdmi output to drive an lcd display for your smart dashboard instruments.
There is considerable duplication of electronics in some of these devices. For example it would be possible to share the input filter caps in the motor control with the output filter caps on the charger since they are never in use at the same time. The same traction pack current sense could be shared across the motor control and the charger and used for the SOC. The same cooling system could be shared between the charger and motor control either air or water.
There would be other advantages like the fact that the chance of an isolation problem would be very low with all the complicated wiring done inside. The overall cost would be less because of the shared electronics. The reliability should be improved. Everything plays nicely with each other. All the high voltage stuff would be contained inside this one box. Only one weatherproof device to mount.
Unfortunately there would be disadvantages as well. You would end up with less choice. The design would need to be over engineered so it could handle more projects. You would probably want the motor control to be able to do 340v and 1000a like the other guys can. The charger would need to be able to do L2 charging from a 30a EVSE or plug into a 115vac outlet in a pinch. You would probably want the DC/DC converter to be able to do 80a. These specs would be overkill for a lot of projects. And if something breaks you can't just swap out that sub assembly. And although the overall cost could be less you are looking at a single device that would be fairly high ticket (at least until we see economies of scale kick in.)
Are there any vendors that could do this now? Sure there are, but will they? Would there be enough demand? Would the liability issues prove to be a killer? I do know I would have bought such a device to save a lot of effort in the course of my conversion.
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