Roger Stockton wrote
> ...Does the manufacturer state a maximum battery wiring inductance value
> that the user must observe, in the same way as they would an input voltage
> range?  Even if they do, how does the hobbyist determine if they are
> within spec or not?...

The hobbyist can estimate the worst-case inductance of a wire in free space
(that is to say, the wire is separated more than 10 diameters from its
return conductor) at around 1uH per meter; placing the forward and return
conductors next to each other, or even twisting them, will dramatically
reduce the inductance. Since energy stored in an inductor is 0.5LI^2 and
energy stored in a capacitor is 0.5CV^2, if you equate the two* you'll see
that it doesn't take much capacitance to deal with any reasonable amount of
inductance in the battery circuit of most EVs. Do I specify this in the
Soliton manual? No. I do recommend that the forward and return cables in the
battery circuit be run together for this reason, as well as to reduce EMI
emissions, but I don't explicitly warn people that too much inductance on
the battery side of the controller will hurt it. I *do* warn about
insufficient inductance on the motor side of the circuit, but that is mainly
to protect PM motors from the effects of high ripple current (catastrophic
demagnetization and/or hysteresis loss heating). NB - I don't know of any
other manufacturer that provides a minimum inductance for the motor
specification, even though it is probably the most important spec to the
controller.

* - e.g., 1000A through 10uH of inductance = 5J = 100V across 1000uF of
capacitance



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