Controlling a big sepex

[jackbauer]

Yep thats it Steve. I need one of these myself for my compound motor.

[stevegaarder]

Thanks, Jack. The next question in my mind is how to handle regen. Do we just put a big diode across the MOSFETS to carry the current (assuming you can't rely on the intrinsic diode), or is there a better way?

[MPaulHolmes]

The regen current is monitored by the current sensor. It can do -900 to 900amp. I think the intrinsic diode would be fine? The hardware overcurrent circuit would have to be modified a bit so as not to allow too much negative current either. Hey, you could do a PI loop to command a certain regen current I think. Maybe the gas pedal could be modified to allow for forward and backward current.

Fran was telling me that SEPEX motors and controllers can regen just about as well as A/C motors and controllers.

[jackbauer]

how goes progress on the boards?

[MPaulHolmes]

These boards? hahaha. The charger and bms is DONE! Just a wee bit more testing, and then I can finally do the gosh dang controller boards!
LiFePO4 bms with CAN. Good for 48 batteries. This is only 3 of the 6 modules:


0-200v input, 0-38amp (am getting a different inductor for higher currents), constant current, then constant voltage (or whatever friggen algorithm I want hahaha) LiFePO4 charger with CANbus and RS-232:


It's a race against the Chevy Volt! The controller is next!

[stevegaarder]

Originally Posted by MPaulHolmes

The regen current is monitored by the current sensor. It can do -900 to 900amp. .

What sensor are you using? I want to buy one to make some measurements, and be able to use it with the controller later.