I’m using a raiden7 VESC on my tow boogie. It’s a nice unit, seems well made, light weight, has screw terminals which useful.
One issue is that it overheats really quickly - from cold 15 seconds at 100amp and it will thermal throttle at 85°C. This is when the VESC is attached to a large aluminium enclosure with thermal paste between the VESC and the enclosure, and it’s winter and only 13°C outside.
The temp drops fast when current is reduced, back down to 30-40°C in under a minute.
Between the PCB and the VESC aluminium base is 1mm thick thermal pad which I’m assuming is the heat transfer bottle neck.
What other options are are there for this pad? I’m thinking a thinner pad as an electrical insulator, and some copper sheet. Or just pump the whole underside with thermal paste, or a graphite pad.
Will any of these option offer substantial improvements?
The PCB should really aluminium for the best heat transfer like many other VESCs.
I had same esc on efoil build. Short board, passive water cooling without pump, I could overheat it after 10 sec. it was impossible to start foiling. I solved my problem partially filling esc box with mineral oil. that gave me 1.5-2 min time trying to get up and foil. when foiling, with water cooling working, esc temp was always 55-60 degrees. I even managed to get thermal throttle while foiling and pushing a little bit harder my foil, outside temp was around 35 degrees and water temp 25 degrees.
Finally, problem was solved with replacing raiden7 with makerX g300 now I can’t raise temp to over 45 degrees whatever I do.
In your case with tow boogie, you won’t have such current drop like on efoil. I would try to lower that 100amp to 70-80amp (that’s battery current we are talking about, right?) and maybe add mineral oil (but beware, mineral oil will find it’s way everywhere, even through silicone wires so everything will be oily) also maybe even bigger heat sink
I have a similar build in progress, Raiden7 on top of the mast, passively cooled… I’m a bit worried now how this is going to turn out.
I will open up the ESC and try to improve thermal conductivity from Mosfets to heatsink.
I can think of:
-thinner cooling pad (0.5mm) in combination with a copper sheet (0.5mm). The copper sheet can be bonded to the aluminium housing with thermal paste.
-with this underside of the PCB, you need some kind of pad. It is very uneven. And electrical isolated as well.
-add a heatsink on top of the MOSFETs as well, this can be a copper sheet (3mm?) fitted around motor terminals.
I have the flipsky 75200 with water cooling.I am passively cooling on a plate which is bolted through the hull to the mast base. Only gets to 37C on my efoil after 20minutes.
I had no problem with heat.
It may also depend on vesc current settings.
My first tests were without cooling in alu box and it was overheating but as soon as I used watercooling the temp is hardly above 60 even after 30min cont. riding.
We have the 75200 PCB version and put the cooling plate directly on the mast base. (cooling paste used)
My dad and I did some static testing on the water some days ago and with WOT (current 120 amps, power around the 3000 watt.).
After 10 minutes we managed to get it up to 47c
We did look at the Raiden7 before we got the 75200. Reading this I am happy we did not get the Raiden.
Your tests show with water cooling, and only running at half the stated continuous current, you are still getting 60C, which is pretty bad. With water cooling you should only really see the water temp +20.
My issue is that with even the best heatsink (ie even a 100kg block of aluminum), or the very best pumped water cooling attached to the base of the controller, the speced continuous current, the reason why i bought it, can only be maintained for less that 15 seconds due to a cooling design fault.
I don’t consider 60°C to be overheating when pushing 90+kg dude above the watter at 30+km/h. The suggested water temp +20 comes to 50+ too so I think it is still pretty good.
concerning the temperature, I don’t exceed 53° on my 13 to 19 km outings (12s12p battery). As for watts/h, the métro.pro works 1 time out of 2, so I’ve stopped consulting the data.
I also have a question:
What are your cutoff start and off parameters on your VESCs? because I stay on my so on every street…
Thank you and good riding
I’m pulling max 100amp, but even at 60 amps continuously it will reach thermal throttle of 80°C in less than a minute. As soon as I slow down the temp will drop rapidly, but never below 60°C.
I filled my entire enclosure with 500ml mineral oil to help with cooling and it worked good for one session reaching about 70°C then quickly dropping down to about 40°C. Had over an hour without any thermal throttling.
On the next session I was seeing similar temps as the first for 30 mins of use, then it would go for 30 seconds, and cut out (not thermally throttle). After 30 seconds I could go again, but only for 30 seconds or so. Current seemed to be limited to about 3/4 of what it was initially as well, so I’m assuming something blew or failed.
Waiting 20 mins for everything to cool to try get home on foil gave the same result.
Even with a suitable water cooling, if the R7-Pro was undersized for efoil use, let’s hope the brand has the courage to say so on each R7 product page.
now I can’t raise temp to over 45 degrees whatever I do.
