I did some more testing. This is measured at supply bus bars at 120 A phase current and 60V input voltage:
The biggest spike zoomed in at t=0:
I cannot go any further with current test setup. I was already melting supply cables and triggering 220V fuse.
Ring frequency is 25 MHz. I'll put some ceramics caps close to FETs in next revision. Seems like current version will handle 200A @ 84V just fine. There is still 66V for spikes before any damage occurs.
Also measured gate voltage with that spring thingy instead long crocodile cable on probe. Looks much better now.
I CNC-ed the bottom housing for my controller and installed it in my bike.
After few tests I set it to full capacity - 200 A motor current in FOC mode. I don't have any nice graphs yes because I'm still waiting for Metr module. Everything seems to run fine. Torque at 200 Amps is just insane. I drained about half the battery and the controller temperature didn't even move for more than 10°C.
Great work man. Looking really awesome!
I 3D printed top housing for BESC.
Another part is used to cover high current terminals. It doubles as mount for 12V 5A DC/DC.
And here it is in my bike.
I did three battery cycles with my bike and everything seems to be working.
Settings for my bike are:
Motor current max
Motor current max brake
Absolute maximum current
Battery current max
Battery current max brake
MOSFET Temp Cutoff Start
Minimum input voltage
Maximum input voltage
Dead Time Compensation
Accelerations are insane except for very low speed. Regenerative braking is useful for going downhill for a long time. It extends battery life for about 20% when riding on road. Doesn't do much when riding offroad because I'm used to mech brakes.
Current bottleneck is my battery. It can output up to 125 A but only does when it holds about 50% of charge or more otherwise voltage drops too much. Motor heats up to 60°C (I'm using hubsink and statorade), BESC up to 65°C during normal riding (~100A average current) and up to 75°C (MOSFET cutoff) if going uphill for a very long time. This should drastically improve now that I added a fan. Before it was just closed in a box with no air circulation.
Current version will be the last since it's good enough. If someone is interested in PCBs or BESC as a kit write me a PM. I also have something beefier than BESC in mind with more than double the current capacity to drive this so stay tuned.
Thanks to anyone who helped. Big thanks to TechAUmNu for schematics and layout ideas and also to Benjamin for writing this wonderful software and keeping VESC project alive.
I installed 40x40x10mm fan to move some air through heatsink. Driver temperature didn't go over 55°C most of the time with peak at 60°C.
Todays muddy ride:
Some nice graphs with current, speed, temperatures, etc.: https://metr.at/r/7XZie
Very impressive work. Subbing.
Hello Galp, Nice project, it is impressive!, It seems than this design is for a bigger project than a bike!
What power do you think it could handle? 16kw?
Hi! I've tested it to ~10 kW. It runs steadily @ 200A phase current and 72 V nominal input voltage.
I am new in vesc.
i want use acs712-30A(current sensor) in my driver. i use 2.4k and 4.7k resistor to convert 2.5 volt to 1.65v but i dont know how much is CURRENT_AMP_GAIN ?
How do i calculate CURRENT_AMP_GAIN and CURRENT_SHUNT_RES?
Can everybody help me?