Direct VESC V4.12

[chaka]

It has been awhile since posting on the sphere but I think there are some members here who will find this new project useful. We have modified the original Kicad files for V4.12 and switched to direct fets for proper cooling with heat sinks. The modified files have been uploaded to our OshPark account for anyone to use. They have passed bench testing and will be tested on a single motor build very soon. Here is a link to the files if you would like to build on your own: https://oshpark.com/shared_projects/6kWeFuuK




I am also working towards a 12 fet version for higher output applications. We should be able to fit it on the original footprint so it will still be very compact!

[MrDude_1]

that picture is interesting to me. I am not sure what a Direct FET is but from your picture it appears the mosfets are in a slimmer metal can package... does this allow for a proper heatpath to a external heatsink? is the outside connected to any of the FET pins?

[chaka]

Yeah, you need to use a thermal adhesive to attach a heat sinks and keep them electrically insulated from the package. This is still very much in the alpha phase and I may make a few more changes before moving into manufacturing these.

[s28400]

Very nice! I look forward to seeing the thermal performance on these! Where do you get the smd placement done after you order from oshpark if you don't mind me asking?
Cheers!

[okp]

great job man. I wish I could try some but manufacturing/prototyping in France is just like... ultra expensive! I wish I had some soldering skills/background.

[chaka]

Very nice! I look forward to seeing the thermal performance on these! Where do you get the smd placement done after you order from oshpark if you don't mind me asking?
Cheers!

We place them here in the shop and send them through our reflow oven. The direct fets were easier than expected to place.

[MrDude_1]

Yeah, you need to use a thermal adhesive to attach a heat sinks and keep them electrically insulated from the package. This is still very much in the alpha phase and I may make a few more changes before moving into manufacturing these.

so in theory if you used a piece of kapton tape over each one (or one piece under the heatsink), you could lay one long heatsink over it on each side... then clamp them to the board somehow (maybe a new screwhole or something similar)

I really like this idea. my #1 problem with the VESC is it didnt have a good heatpath for the FETs.. its an excellent controller, but I didnt know how to fix that without changing the entire board... this is a huge breakthrough. (for anyone that has the tools to solder these types of devices)

[chaka]

Kapton might not be the best material. I use it to insulate plastic jst headers when reworking circuit boards. Better to use something like this: https://www.amazon.com/dp/B019MV1TAC/re ... B019MU7NTO

All that is really needed to assemble these is a smd station with a hot air attachment.

We are machining a double sided aluminum case instead of using commonly available heat sinks. You could use the two mounting holes near the phase wires to mechanically fasten some heat sink strips but I am thinking more thermal mass will perform better.

We may make a few more changes to the pcb layout and BOM so I would hold off from building from these files if you want something more polished and final. As stated earlier, we are doubling the amount of fets on the vesc also. If it tests well it may be a great addition for ebikes. Might handle as much as 100 amps constant or more? Time will tell.

[s28400]

Very nice!! 100 amps sounds juicy! I'd be curious to see what kind of heat those fets throw at that current. Also, do you have a price range in mind for these units when you are finished? Keep us updated!
Cheers!

[MrDude_1]

Kapton might not be the best material. I use it to insulate plastic jst headers when reworking circuit boards. Better to use something like this: https://www.amazon.com/dp/B019MV1TAC/re ... B019MU7NTO

All that is really needed to assemble these is a smd station with a hot air attachment.

We are machining a double sided aluminum case instead of using commonly available heat sinks. You could use the two mounting holes near the phase wires to mechanically fasten some heat sink strips but I am thinking more thermal mass will perform better.

We may make a few more changes to the pcb layout and BOM so I would hold off from building from these files if you want something more polished and final. As stated earlier, we are doubling the amount of fets on the vesc also. If it tests well it may be a great addition for ebikes. Might handle as much as 100 amps constant or more? Time will tell.

the case sounds cool, but will it make it more difficult to mount to a skateboard?
I know you're going for power, but have you tried a version where all 6 FETs are on the same side of the board? this means it can be mounted to a non-airflow side (like the skateboard) and have the heatsink large with fins in the air (facing out)??

[Jan Christian]

Maybe you should wait for the vesc 5.0 and build on that? The erpm also needs to be juiced up for other applications..

[chaka]

For us space is always an issue since we integrate everything into a cavity only 20mm deep and our electronics need to fit into a cavity around 50mm wide so v4.12 is a good fit. Once v6 goes public we will likely rework the pcb files and make a more compact version to suit our needs but it will be more costly so we will still manufacture version 4.12 to keep a lower cost alternative.

We could add all the fets to one side but we have the space for 6 more fets on the original footprint so why not jump up to 12 fets! The encased VESC will only be about 13mm thick so it will be very easy to mount inside an enclosure.

[Ecyclist]

For us space is always an issue since we integrate everything into a cavity only 20mm deep and our electronics need to fit into a cavity around 50mm wide so v4.12 is a good fit. Once v6 goes public we will likely rework the pcb files and make a more compact version to suit our needs but it will be more costly so we will still manufacture version 4.12 to keep a lower cost alternative.

We could add all the fets to one side but we have the space for 6 more fets on the original footprint so why not jump up to 12 fets! The encased VESC will only be about 13mm thick so it will be very easy to mount inside an enclosure.

I'm using VESC v4.12 on my e-bike. I built a heatsink case and I would like to use Direct FETs with original v4.12 PCB.
Is that doable? Is a new v4.12 VESC with Direct FETs available?

VESC case.JPG (79.85 KiB) Viewed 3030 times

[dirkdiggler]

Seriously! How cool is it to have such a small, but powerful controller that you can mount to a seat post? Someday, I'll venture into the VESC world. Should of done that for my e-skateboards a long time ago. I'm hoping they start making a 72v version that will put out 200 amps sooner than later.

[chuttney1]

I'll have to post this notice since it seems to be only mentioned on esk8.builders site. Ollin has stated he will no longer be producing components for the DIY market and moving towards completes. So it's bye-bye all the high quality VESCs from him.

[Hummina Shadeeba]

but he does post the guide and says its easy to do! I've never done it.

[xachmo]

Looks like this Oshpark link is no longer active, could you send an updated link?

Thank you! this is a great project

It has been awhile since posting on the sphere but I think there are some members here who will find this new project useful. We have modified the original Kicad files for V4.12 and switched to direct fets for proper cooling with heat sinks. The modified files have been uploaded to our OshPark account for anyone to use. They have passed bench testing and will be tested on a single motor build very soon. Here is a link to the files if you would like to build on your own: https://oshpark.com/shared_projects/6kWeFuuK




I am also working towards a 12 fet version for higher output applications. We should be able to fit it on the original footprint so it will still be very compact!