Paul & Sabrina's cheap DIY 144v motor controller

[Georgia Tech]

Boy...sorry to here this Paul.... It would hurt me too
I Corinthians Ch 15

[mobby666]

Sorry mate, I lost my Mom in very similar circumstances, I won't pretend to know how you feel, I only know How I felt.

[reissmachinist]

In the Open ReVolt/Fab Files is "Note: Rev 2D uses heavy duty PCB
powerboard as opposed to milled copper/fibreglass boards".
What is heavy duty PCB powerboard? Is it something other than 4 oz.
copper/ per sq. ft. double sided pc board like Paul H was selling?
I have to make another one.
Thanks, Larry Reiss

[reissmachinist]

Can anyone tell me what the width of the cuts are between the traces
on the power board? Some one wrote that they used a 1/8 in. vee shaped
cutter. So it's unclear to me what the width of the cuts actually are. It all
depends how deep the cut is.
On my power board that had the magic smoke escape, I milled the cuts
.050 in wide. Maybe that wasn't wide enough for 180 volts.
Thanks, Larry Reiss

[MPaulHolmes]

My cuts are probably 0.08" wide. I don't know if 0.05" would be enough or not for 180v. Maybe there was a wisker of copper that bridged it, and then that allowed a torrent of current to keep going? I don't know what I"m talking about though.

The rev D board is 4 ounce copper on each side. It's just made by an actual board house, with solder mask and stuff. It's really nice. I've got to make myself one of those buggers.

[voltmatic automaton]

So I got my Logisystems Revolt hybrid up and running
Great use of the power stage considering there was nothing really wrong with it. I took the car out and everything is good, except for heat.
There is a fairly good heatsink installed on the LS power stage, except that its fins could be bigger. Other than actual physical alterations though is there a possibility of altering some of the PWM or other software parameters that would decrease the heat output?

If not then can someone suggest relatively easy thermal management solutions (read cheap)


thanks!!!

[jackbauer]

does the LS power stage use mosfets or igbts? I suspect i read somewhere its igbts. If so your probably not driving them at full capacity with a stock control board. What gate resistors are you using? Also consider another resistor and fast recovery diode in inverse parallel to aid turn off.

[voltmatic automaton]

the gate resistors were built into the power stage of the LS board and yes the board uses IGBTs.

A forum member on DIYelectric said i could just gofrom the control board to the power stage with no other mods, which is right but the heat is a bit of a problem for speeds over 45 and if i have to merge with traffic forget it, the heat gets to where it cuts back very quickly.

i'm not an engineer so if i have to make modifications can you tell me in a way i'll understand?

thanks!!

[voltmatic automaton]

ok, so i found your diagram for the circuit using an IGBT setup.

let me figure this correctly.
the way i have it now, the control board (revolt), i use one of the GR pads to run a line from the control board to the LS power stage. I did this because the Gate Resistors are in the power stage of the LS controller.
For the LS, there is a single pin that this line was soldered into.

If i go with the IGBTs, should i just make a small board to insert between the control and power stage so that it will produce the same signal effect?

[jyanof]

Originally Posted by voltmatic automaton

There is a fairly good heatsink installed on the LS power stage, except that its fins could be bigger. Other than actual physical alterations though is there a possibility of altering some of the PWM or other software parameters that would decrease the heat output?

If not then can someone suggest relatively easy thermal management solutions (read cheap)


thanks!!!

if there are IGBTs in there, the gates should probably be driven up to 15v. if you're using the control board output to drive them, the cincon DCDC is providing the gate power and it's only 12V for the mosfets. At 12V, the IGBT's won't turn on all the way and will create a lot of heat. I think there is a version of that DCDC that has an output of 15V.

There's also the gate resistor thing mentioned earlier, but sounds like that's hard wired in...