Quote:
Originally Posted by The Toecutter
The Arduino board gave no problems and the truck drove around fine on that using the same exact power stage setup.
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Those darlington modules require far more POWER to drive than FET's
or even IGBT modules with a similar power rating.
Perhaps as much as 80 times more power!
They also have "turn off" issues due to their tendency to saturate.
A "baker clamp" in the drive circuitry would help with that.
Still, there are other people using that module, and you've been driving
with them for a year, so the Revolt controller can be made to work with them.
It will take a bit of driver circuit fiddling to get there.
Edit: Also might want to slow the PWM down to 1.5 khz
Does the power stage still use 4 or 5 of these modules?
The Revolt controller might drive a single one of those modules directly with it's driver,
but it won't drive any more than that without adding additional drive circuitry.
What exactly is the driver circuit when driven by Arduino?
Is it still Solid State Relays? and if so, what is the exact base drive circuit?
Does the Revolt controller drive SSR's or is it driving the modules through
a base drive resistor?
What is the base drive resistor value, type, and power rating?
It should probably be on the order of 1 or 2 ohms, non-inductive, and 10 watt power rating.
There should be a separate base drive resistor for each module.
Clearer pictures and schematics would be helpful if that is possible.
It does look like there might be one substitution cap
used in the build of the Revolt controller, though that is not very
likely an issue here, only a very minor detail.
These old eyes just can't make out much else because of the focus.
Did you check the modules to see if the there was a short to the case after they failed?
From what I have been able to find, the truck build looks well done.
Are there "solid state rated" fuses in the battery loop?
If so, what is the current rating? Did it blow when the batteries went thermal?
I am at a loss as to where all of that battery current went.
It certainly did not flow through the Revolt control board or it would
have been vaporized!
And was it the power modules that failed?
FETs and IGBTs have been cited as blowing, so I am a bit confused as to
whether a driver component failed, or did the power module(s) fail?
Do you have a battery resistance meter, or were you measuring the
resistance of the batteries with a multi-meter?
Yes, a lot of questions.
I'm thinking that the answers will allow us to help with the solution.
Mark